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The Bird Guide North America

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To birds, for providing me with an endless sense of discovery, beauty, and wonder. To eBirders, who have tirelessly recorded your observations and reshaped what we know about birds—in so many ways, this is your field guide. To my parents, Joyce and Ken Sullivan, for giving me the freedom to chase what I love. And to my family, Ella Sullivan, and Sophie De Beukelaer—because of you, and through you, I’ve learned why all this matters. Brian Sullivan To Paul O’Brien for sparking my interest in birds. To Louise Zemaitis, who worked as hard as I did on this book through her patience and unwavering support. And to all the participants on my tours and workshops—you taught me how to teach. Michael O’Brien

To my parents, Russell and Janet Wood, for encouraging my curiosity and love of birds from the very beginning. To Jessie Barry, for her patience, support, and generosity through the long journey of this book. To the eBird community, whose shared observations have given birding even greater meaning. And to everyone who takes the next step to make the world better for birds and the habitats on which they depend. Chris Wood To all museum personnel and to the specimen collectors of yore, upon whose shoulders all new work is built. Steve N. G. Howell To my wife, Debbie, for her enduring and stoic support and love throughout my years of obsession. To my dad, Jack Lewington, for kindling my interest in natural history, and to my brother, Richard, for inspiring me to paint what I loved. Ian Lewington To my mother, Donatella; to my father, Giuseppe; and to my brothers, Alessandro and Antonio. And to those who spend their lives traveling, from those crossing a hedge to those crossing the globe. Lorenzo Starnini

The Cornell Lab of Ornithology thanks the Mark Pigott Family for its generous support of this publication.

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The Bird Guide North America Brian L. Sullivan, Michael O’Brien, Christopher Wood, and Steve N. G. Howell Illustrated by Ian Lewington and Lorenzo Starnini

PRINCETON UNIVERSITY PRESS PRINCETON AND OXFORD

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Princeton University Press is committed to the protection of copyright and the intellectual property our authors entrust to us. Copyright promotes the progress and integrity of knowledge created by humans. By engaging with an authorized copy of this work, you are supporting creators and the global exchange of ideas. As this work is protected by copyright, any reproduction or distribution of it in any form for any purpose requires permission; permission requests should be sent to permissions@press.princeton.edu. Ingestion or use of any Princeton University Press intellectual property for any AI purposes is strictly prohibited without a license to do so; licensing requests should be sent to DigitalLicensing@press.princeton.edu. Published by Princeton University Press 41 William Street, Princeton, New Jersey 08540 99 Banbury Road, Oxford OX2 6JX press.princeton.edu GPSR Authorized Representative: Easy Access System Europe - Mustamäe tee 50, 10621 Tallinn, Estonia, gpsr.requests@easproject.com All Rights Reserved ISBN (pbk.) 9780691137278 ISBN (PDF) 9780691296302 [[Library of Congress LCCN still to come]] British Library Cataloging-in-Publication Data is available Editorial: Robert Kirk and Megan Michel Mendonça Production Editorial: Mark Bellis Text Design: Rob Still Cover Design: Ben Higgins Production: Steve Sears Publicity: Matthew Taylor and Caitlyn Robson-Iszatt Copyeditor: Amy Hughes Cover image © Ian Lewington Data from eBird Status and Trends provided by the Cornell Lab of Ornithology Fink, D., T. Auer, A. Johnston, M. Strimas-Mackey, O. Robinson, S. Ligocki, W. Hochachka, L. Jaromczyk, C. Wood, I. Davies, M. Iliff, L. Seitz. 2021. eBird Status and Trends, Data Version: 2020; Released: 2021. Cornell Lab of Ornithology, Ithaca, New York. https://doi.org/10.2173/ ebirdst.2020 This book has been composed in Adobe Garamond Pro and Myriad Pro Printed in Italy

10 9 8 7 6 5 4 3 2 1

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CONTENTS

ACKNOWLEDGMENTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

Why Birds? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Why Birding? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 About This Book . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 Abbreviations and Terminology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 Bird Topography . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 Molt and Aging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 Identifying Birds . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 Cornell Lab of Ornithology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

SPECIES ACCOUNTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 SWIMMING WATERBIRDS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 Swans . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Geese . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Ducks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Cormorants . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Loons . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Grebes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Alcids . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

FLYING WATERBIRDS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Petrels, Albatrosses, and Storm-Petrels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Frigatebirds and Tropicbirds . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Boobies and Gannet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Pelicans . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Jaegers and Skuas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Gulls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Skimmer and Terns . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

30 32 40 74 78 84 88

100 100 120 122 126 128 136 164

WALKING WATERBIRDS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

176 Plovers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 180 Oystercatchers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 186 Stilts and Avocets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 186 Sandpipers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 188 Bitterns, Herons, and Egrets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 214 Cranes and Wood Stork . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 224 Ibises, Spoonbill, Flamingos, and Limpkin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 226 Rails, Gallinules, and Coots . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 230

GAMEBIRDS AND ALLIES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 236 Quail . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 236 Chachalaca . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 238 Pheasants, Grouse, and Allies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 238

DIURNAL RAPTORS AND OWLS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Vultures and Caracara . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Eagles and Osprey . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Hawks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Accipiter and Astur . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Harrier . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Kites . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Falcons . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Owls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . For general queries, contact info@press.princeton.edu.

248 250 254 258 270 274 274 278 284

LARGER LANDBIRDS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 298 Nightjars and Nighthawks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Pigeons and Doves . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Cuckoos and Allies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Parrots . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Kingfishers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Trogons . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Woodpeckers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Crows, Jays, and Magpies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

298 304 310 314 318 318 320 334

AERIAL LANDBIRDS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 346 Hummingbirds . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 346 Swifts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 358 Swallows . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 360

SONGBIRDS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 366 Tyrant Flycatchers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Shrikes and Becard . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Thrashers, Mockingbird, and Catbird . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Thrushes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Old World Flycatchers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Waxwings, Phainopepla, and Dipper . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Chickadees and Titmice . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Nuthatches . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Creeper, Verdin, Bushtit, and Wrentit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Wrens . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Gnatcatchers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Kinglets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Vireos . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Old World Warblers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . New World Warblers and Olive Warbler . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Wagtails and Pipits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Larks, Longspurs, and Snow Bunting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . New World Sparrows . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Old World Sparrows . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Tanagers and Allies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Finches . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Cardinalids . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Blackbirds and Orioles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Starlings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Bulbuls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

366 390 392 398 408 410 412 418 420 422 428 430 430 438 440 476 480 486 520 522 524 540 552 570 570

APPENDICES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 572 A. Rare Bird Species Accounts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 572 B. Exceptional Rarities Recorded in North America (as of 31 December 2025) . . . . 605 C. Extinct Species . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 606 Artists’ Credits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 607

INDEX OF SPECIES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 608

For general queries, contact info@press.princeton.edu.

Acknowledgments

Foremost, we thank Robert Kirk, Publisher, Nature Books at Princeton University Press, for his vision, thoughtfulness, and patience in helping us see this project through from start to finish. Also at the Press, we’re grateful to Rob Still for his meticulous text design work, to associate managing editor Mark Bellis, and to nature publications coordinator Megan Michel Mendonça. Thanks also to copyeditor Amy K. Hughes, who greatly improved the consistency and content of this manuscript through her review. Several individuals reviewed early versions of this book and provided critically important feedback, and we thank them separately here: Marshall Iliff, Andrew Spencer, Luke Seitz, and Jessie Barry. When we started this project, eBird was in its infancy, Merlin didn’t yet exist, and Birds of the World was just a dream. The development of these platforms has transformed our understanding of birds and provided the backbone for much of the new information found in this book. We thank the dedicated teams at the Cornell Lab and its partners around the world who work together to make these projects possible. Special thanks to the thousands of eBird reviewers who volunteer their time and expertise to improve data quality. We thank the following institutions for providing essential support, access to collections, and collaboration throughout this project: Academy of Natural Sciences, Philadelphia; American Museum of Natural History, New York; California Academy of Sciences, San Francisco; Cape May Bird Observatory; Cornell Lab of Ornithology; Cornell Museum of Vertebrates, Ithaca, NY; Museum of Vertebrate Zoology, University of California, Berkeley; Natural History Museum, Tring, UK; Point Blue Conservation Science; Smithsonian National Museum of Natural History, Washington, DC; Victor Emanuel Nature Tours; WINGS Birding Tours Worldwide. Over the course of this project, we shared countless memorable encounters with people and birds that taught us so much. The people listed here helped us significantly by sharing their knowledge and expertise about birds. We also thank our families and other key supporters who sustained us through this work: Mark Adams, Jody Allair, Gautam Apte, Bruce Anderson, George Armistead, Tom Auer, Parker Backstrom, Jessie Barry, Mitchell Barry, Barb Bassett, Hope Batcheller, Bob Behrstock, Chris Benesh, Humberto Berlanga, Bob Berry, Karen Bills, Patricia Briceño, Ned Brinkley, Jen Brumfield, Ken Burrell, Mike Burrell, Dick Cannings, Lizzy Brewer Chouinard, Anne Condon, Jack Connor, Mark Constantine, Elaine Cook, Chris Corben, Renée Cormier, Andrea Corso, Cameron Cox, Richard Crossley, Jenna Curtis, Ian Davies, Jeff Davies, Christina Davis, Glenn Davis, Michelle Davis, Josep del Hoyo, Dave DeSante, Mark Dettling, Jim Dowdell, Adriaan Dokter, Andrew Dreelin, Jennie Duberstein, Katy Duffy, Jon Dunn, Pete Dunne, Dale Dyer, Vince Elia, Hap Ellis, Victor Emanuel, Richard A. Erickson, Bill Evans, Andrew Farnsworth, Paul Fenwick, Dick Filby, Daniel Fink, Shawneen Finnegan, John Fitzpatrick, Molly Fitzpatrick, Ted Floyd, Don Freiday, Terry Fuller, Mark Garland, Martin Garner, John Garrett, Jeff Gerbracht, Brian Gibbons, Doug Gochfeld, Mary Gustafson, Pete Gustas, Andy Guthrie, Martin Hallam, Nic Hallam, Catherine Hamilton, Cullen Hanks, Keith Hansen, Diane Hart, Peter Hart, Skye Hass, Dave Hedeen, Meg Hedeen, Burr Heneman, Stephanie Herron, Catherine Hickey, Mark Hoffman, Julian Hough, Rich Hoyer, Alec Humann, Diana Humple, Marshall Iliff, Jasdev Imani, Daniel Irons, Alvaro Jaramillo, Andy Johnson, Tom Johnson, Kenn Kaufman, Kim Kaufman, Brooke Keeney, Steve Kelling, Joey Kellner, Paul Kerlinger, Eric Kershner, Guy Kirwan, Robby Kohley, Karen Kreiger, Denise Landau, Dan Lane, Michael Lanzone, David La Puma, Alexander Lees, Paul Lehman, Tim Lenz, Tony Leukering, Jerry Liguori, Sherry Liguori, Ben Loehnen, Taylor Long, Irby Lovette, Barry Lyon, Linda Macaulay, Stu Mackenzie, Andrew Marden, Ron Martin, Blake Matheson, Jay McGowan, Jimmy McMorran, Steve Mlodinow, Whitney Mortimer, Sue Morris, Will Morris, Killian Mullarney, Frank Nicoletti, Martina Nordstrand, Raphaël Nussbaumer, Evan Obercian, Barbara O’Brien, John O’Brien, Paul O’Brien, Amy O’Neill, Ian Owens, Brian Patteson, Brandon Percival, Ian Paulsen, Nathan Pieplow, Paul Pisano, Zak Pohlen, Lina Prairie, Bill Pranty, Peter Pyle, Pam Rasmussen, Aaron Reb, Jerald Reb, Tom Reed, Marc Regnier, Van Remsen, Virginia Rettig, Nicole Richardson, Melissa Roach, Don Roberson, Charlie Roberto, Bryce Robinson, Amanda Rodewald, Chente Rodriguez, Ryan Rodriguez, Danny Rogers, Gary Rosenberg, Ken Rosenberg, Vanya Rohwer, Will Russell, Tom Schulenberg, Tom Schultz, Wendy Schultz, Cooper Scollan, Glenn Seeholzer, Luke Seitz, Willie Sekula, Bill Seng, Nate Senner, Debi Shearwater, David Sibley, David Simpson, Alec Smith, Bradley Smith, Jerry Smith, Jennifer Speers, Andrew Spencer, Michael Stubblefield, Kate Sutherland, Clay Sutton, Pat Sutton, Peder Svingen, Benjamin Van Doren, Grant Van Horn, Juan Diego Vargas, Alison Vilag, Gerrit Vyn, Dick Walton, Dave Ward, Maili Waters, Sophie Webb, David Weber, Drew Weber, Mike Webster, Janet Wessel, Geoff Wyatt, Roger Wyatt, Matthew Young, Louise Zemaitis, Kirk Zufelt. For general queries, contact info@press.princeton.edu.

INTRODUCTION Why Birds?

Across the planet, birds connect people to nature in ways few other animals can. Their beauty and songs draw us in, while their presence—and absence—reveal changes in the world around us. From the world’s highest peaks to its most remote oceanic waters, birds find a way to survive. For many people, birds are the most visible and familiar form of wild nature: they live in our backyards, fill our skies with movement and sound, and raise their families alongside ours. Their proximity makes them among the most widely admired and best-known animals on earth. That familiarity invites curiosity. Birds encourage us to look more closely, to ask questions, and to notice patterns: What is that bird? Why is it here today? Where did it come from? Why does it sing now, and how does its voice change with the seasons? By paying attention to birds, we become more attuned to the natural world as a whole, developing a deeper awareness of the landscapes and ecosystems we share.

Why Birding? If you enjoy watching birds, you’re a “birder.” Yes, admit it. Embrace it. Tell your friends. You’re not alone. By some accounts, as many as 80 million people watch birds in North America, and birding has grown rapidly in the past 5 years as more people seek a renewed connection with the outdoors. Technology has helped spur this growth. The free Merlin Bird ID app has been downloaded by tens of millions of people, making birding more popular and more accessible than ever before. And eBird, an app that gathers bird observations from a global network of birders for science and conservation, is by many measures the largest citizen-science project in the world. So what, exactly, is “birding”? At its most basic, birding is simply the act of watching and identifying birds. But birding can take many forms, much like music: we may all enjoy it, but not in exactly the same way. For some, birding means a few quiet minutes with a cup of coffee watching birds at a feeder. For others, “listing” becomes a serious pursuit, leading them across continents in search of new species. Neither approach is better or worse. Most birders fall somewhere in between—curious about identification and wanting to build their skills, willing to explore locally for new birds, and motivated to protect the birds and habitats they come to know and love. That flexibility is precisely what makes birding so widely appealing. Birding, at its best, takes one out of the daily grind of life and puts us into the present moment. Our senses sharpen, as our eyes and ears work together to detect movement, shape, color, and sound, turning fleeting impressions into recognition and understanding. There is little room for distraction— only attention. This focused immersion in nature is deeply restorative, akin to meditation, and plays an important role in human well-being. Birding challenges our minds, hones our senses, and draws us outdoors, revealing new questions and discoveries even in familiar places. This book is written in support of that experience—it is for everyone who wishes to see birds more clearly, understand them more deeply, and enjoy the process of learning along the way. Lazuli Bunting

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About This Book

Area and Species Covered This guide covers birds found regularly in North America north of Mexico, including marine waters out to 200 nautical miles (370 km) offshore. This region encompasses great habitat diversity, from frozen High Arctic tundra to sweltering mangrove swamps, from eastern broadleaf forests to southwestern deserts. Approximately 1,070 bird species have been recorded in this region through 31 December 2025, out of roughly 11,170 species worldwide. Several hundred of these species are vagrants—birds that appear only occasionally and are not part of the region’s regular avifauna. Because most vagrants are very unlikely to be encountered, they are not included in the main plates of this book. More frequently occurring rarities (mainly those with more than 10 individuals recorded in eBird over the past 20 years) are treated with brief accounts and minimal illustrations in Appendix A. Exceptional vagrants (fewer than 10 records in total) are listed in Appendix B.

Format The guide’s inside front cover comprises pictorial contents to help users quickly zero in on the right group of birds. Begin by matching the bird you’re seeing—its size, shape, and overall look—to the examples in the pictorial contents. Placing a bird in the correct group is the first and most important step in identification; if you’re searching for a duck among hawks, as they say, “you can’t get there from here.” Because this guide is designed for field use, bird families are arranged in an intuitive sequence based on appearance and identification cues rather than in a strictly phylogenetic order. In many cases, birds that look and behave similarly do so not because they are closely related but because convergent evolution has shaped them to fill similar ecological roles. By all means, dive into the fascinating world of taxonomy and discover, for example, that vireos are more closely related to crows than they are to warblers—but for the purposes of a field guide, we place vireos alongside the warblers with which they are most often confused. Our taxonomy and nomenclature follow those used by eBird (J. F. Clements, P. C. Rasmussen, T. S. Schulenberg, M. J. Iliff, J. A. Gerbracht, D. Lepage, A. Spencer, S. M. Billerman, B. L. Sullivan, M. Smith, and C. L. Wood, 2026, The eBird/Clements Checklist of Birds of the World: v2026, https://www. birds.cornell.edu/clementschecklist/download/).

Plates Species are grouped on the main plates primarily by visual similarity, along with shared habitat and geographic distribution. As a result, birds that are likely to be encountered together—and most easily confused—are usually shown on the same plate or on adjacent plates. Main illustrations on each plate are shown at a consistent, larger scale to aid comparison. Smaller images are used to depict less frequently encountered plumages, such as juveniles, geographic variants, or other less common forms. When multiple ages or sexes are shown, images are generally arranged with juveniles and immatures on the left, and adults on the right (typically females, then males). Images without age or sex labels represent adult birds in which the sexes appear similar; many first-year songbirds, for example, are indistinguishable from adults after molting out of their briefly held juvenile plumage. When relevant, juveniles, immatures, males, and females are labeled explicitly. The terms “breeding” and “nonbreeding” (abbreviated as “br” and “nonbr”) apply only to adults, and well-defined seasonal plumages are often accompanied by month ranges indicating when they are typically observed. Geographic variation within a species is usually shown from northwest to southeast, left to right, and all variants are clearly labeled.

Family and Genus Accounts Each family—and some genera or species groups—opens with a brief overview of shared characteristics. Families represented by a single species in North America may not have a separate family account, though the family is noted in the species account. The number of regularly occurring species in each family is given, followed by the number of vagrants recorded in North America and treated in the appendices.

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Species Accounts

Each species account begins with the bird’s English common and scientific names, plus length (L), sometimes wingspan (WS), and weight (Wt). Length, given in centimeters (cm), is generally measured from bill tip to tail tip (unless otherwise specified); and weight is in grams (g) or kilograms (kg). Measurements are drawn from specimens and published sources and are intended to convey relative size, not to provide a comprehensive treatment of morphometrics. The species account text then focuses on features most relevant to identification, including habitat, seasonal occurrence, abundance, and behavior, as well as the more conventional criteria of shape, plumage, and voice (see “Identifying Birds,” below). Subspecies common names are aligned with those presented in eBird. When a field-identifiable subspecies group is named in eBird, we provide that common name and scientific name in the species account. When geographic variation is mentioned but the birds are not generally field identifiable at the subspecies group level, we do not provide a common name or a subspecies trinomial. Sounds: Vocalizations are often essential for identification, but they are notoriously difficult to describe— and birds produce a far wider range of sounds than any book can fully capture. Our goal is therefore to focus on the most commonly heard sounds, with more detailed treatment in groups where vocalizations are especially important for field identification (such as rails and warblers), and lighter coverage where sounds tend to be less critical (for example, many seabirds and waterfowl). Because recordings of bird sounds are now widely available through tools like Merlin, the sound descriptions in this guide are intended to highlight key auditory “field marks” rather than serve as complete representations. We may emphasize elements such as pace (e.g., 2 notes per second), pitch relative to similar species, or overall structure. Phonetic renderings are often used to convey rhythm and quality, with the understanding that they work best when paired with listening to recordings. In a few cases where vocalizations are especially critical to identification, we include spectrograms— visual representations of sound—which can reveal details that are difficult to convey in words alone. Sound descriptions are based on our own personal experience, including reference to the online sound libraries of the Macaulay Library at the Cornell Lab of Ornithology (www.macaulaylibrary.org) and Xenocanto (www.xeno-canto.org). This section is omitted if a species is typically silent in North America (e.g., many seabirds). Eastern Whippoor-will song

WILL whip-poor

hms

0:01.0

time scale for longer songs

Swainson’s Thrush flight call

Alder Flycatcher song 10k 9k 8k 7k 6k 5k 4k 3k 2k 1k

zwee hms

10k 9k 8k 7k 6k 5k 4k 3k 2k 1k

bee-o

0:00.5

0:01.0

beginning steep = hard p sound

hms

rising whistle

0.05

0.10

time scale for shorter songs

0.15

0.20

end burry, fading

0.25

0.30

10k 9k 8k 7k 6k 5k 4k 3k 2k 1k 0.35

time scale for call note

Spectrograms are visual representations of sounds, with time on the horizontal x-axis (hms: hrs:mins:secs) and pitch (frequency) on the vertical y-axis; darkness of the signal indicates loudness. Spectrograms presented in this guide will be on varied time scales, measured either in seconds (for longer sounds such as most songs) or milliseconds (for shorter sounds such as call notes and short songs). The longer scale reveals broad patterns of syllable length and spacing, overall pitch, pitch change, and loudness. Shorter scales reveal more subtle details that would be too compressed to see at a longer scale. With practice, a sense of tonal quality can be discerned from spectrograms: a steep or vertical line sounds like a hard click or chip; a solid level line sounds whistled; stacks of level lines (harmonics and overtones) may sound nasal to hollow; a fuzzy line may sound harsh or hissy; a jagged line (on a short time scale) sounds buzzy or burry.

Status: Status includes general abundance and seasonality for each species. This information should be used in conjunction with the range maps (see below) to understand the probability of encountering a species at a given place and time. Species are assumed to be resident unless stated otherwise. For migratory species, the main migration windows are given and sometimes expanded upon by geography. World range is summarized at the end of the Status section. For general queries, contact info@press.princeton.edu.

Abundance: Abundance terms are relative and averaged over several years and across most of the range. Many species tend to be less numerous toward the edges of their range. Ideally, these terms give the reader some sense of the likelihood of encountering the species. • Common: encountered (seen or heard) on most or all days in range and habitat/season, often in relatively large numbers. • Fairly common: encountered (seen or heard) on most days in range and habitat/season, in smaller numbers than common species. • Uncommon: seen regularly in range and habitat/season, but not every day and usually in small numbers. • Scarce: species that appear rare, perhaps due more to their behavior than to actual rarity. • Rare: species that occur in low density, missed far more often than encountered (seen or heard) on a day in the field, and perhaps encountered only a few times a year; should be documented carefully. • Exceptional [= accidental]: at most a handful of records; not to be expected and should be documented carefully. • Irregular/Irruptive: abundance varies appreciably between years, typically relating to factors such as food supply or breeding success. Range Maps: Range maps accompany each species account, except in cases where the species does not breed in North America and/or its range and occurrence patterns are better represented as text. Range maps provide a quick reference for understanding the core areas where a species occurs. For simplicity, we have focused the range map polygons on these three life stages: breeding (pink), migration (yellow), and nonbreeding (blue). A single year-round occurrence polygon (purple) is used for resident species and to highlight areas where migratory species both breed and spend the winter. Note that this system works perfectly well for species that breed in North America. But it can be confusing for those that breed in the Southern Hemisphere (e.g., many seabirds) and spend their nonbreeding season in North America. In these cases, Key we have used the life-stage colors as listed elsewhere, but all-year breeding nonbreeding migration be aware that for some species, blue doesn’t necessarily equate to the winter season in North America; rather, it means nonbreeding, which can actually be during the North American summer for many species. Immatures of many species oversummer in their core winter ranges (e.g., scoters, shorebirds), but these oversummering populations are generally not mapped. Likewise, areas of rare occurrence are not shown, as there is no clearcut way to determine how to map such occurrences. Many species occur as vagrants well outside the mapped ranges shown here. Range maps in this guide are based on modeled data derived from eBird observations. Individual eBird records are incorporated into statistical models that account for differences in observer effort, skill, and sampling coverage, enabling more consistent estimates of occurrence patterns across space and time. These models generate the core range polygons shown here. Where necessary, we refined the modeled maps to better reflect known species occurrences in areas with sparse data or limited model performance, such as parts of the High Arctic. As in any printed guide, the maps presented here depict generalized ranges based on the best information available at the time of publication. Bird distributions, however, are dynamic. Many species are expanding or contracting their ranges in response to climate change; some—particularly insectivores— are declining; and extreme weather events increasingly displace birds far from their typical ranges. For these reasons, range maps in this book are best used alongside dynamic resources such as eBird that provide up-to-date information on local distributions, recent range changes, and real-time movements. For general queries, contact info@press.princeton.edu.

Abbreviations and Terminology

We have limited the use of abbreviations and have used widely understood terms for geography, habitats, bird topography, and related terms. Nonetheless, a few terms may be unfamiliar to some readers and are explained below.

General Abbreviations We use the standard 2-letter codes for US states and Canadian provinces and territories; 3-letter abbreviations for months (e.g., Jun = June, Sep = September); standard abbreviations for directions: cen. for central, and n., s., e., w. (and n.-cen., ne., nw., etc.) for north, south, east, west (capitalized for major regions, as in N America, S America, etc.); Mts for Mountains; and Co./Cos. for County/Counties. For plumages we use nonbr for nonbreeding, br for breeding, ad for adult, subad for subadult, juv for juvenile (a bird in its first non-downy [= juvenile] plumage), and imm for immature (any nonadult plumage, including juvenile). We use ♀ for female, ♂ for male, 1st-w for 1st-winter, and 1st-s for 1st-summer. We use 1st-yr for 1st-year, 2nd-yr for 2nd-year, etc. We use L for length, WS for wingspan, and Wt for weight. We use ssp for subspecies and, occasionally, sp for species. Finally, in some places, we use ID for “identification” and the Latin abbreviation cf. for “compare.”

Bird-Related Terminology adult allopatric alula backcross boreal forest

bottomland forest breeding plumage call canopy cere chip circum-Gulf migrant cline (adj., clinal) complex song contact call coverts culmen dawn song dihedral

A bird that has reached breeding age and attained adult plumage. Occurring in separate nonoverlapping geographical areas. Small group of strong, stiff feathers at the bend of the wing, important for maneuverability in flight. A backcross hybrid is produced when the offspring of two parent taxa breed with one of the parent taxa. Northern forest that is the world’s largest land-based biome, characterized by its coniferdominant forests and cold climate; in North America, the boreal forest extends from interior Alaska across most of Canada to the Atlantic Coast, reaching south into the northern Great Lakes region and northern New England. Also known as taiga. Deciduous and evergreen hardwood forest found in broad lowland floodplains along large rivers and lakes. Adult plumage worn during the breeding season; typically brighter or more elaborate than nonbreeding plumage for the purpose of mate attraction and territory defense. Generic term covering any non-song vocalization; usually much shorter than songs but can be repeated steadily. Uppermost forest layer formed by the crowns of mature trees; typically denser than mid-story or understory layers. A bare leathery patch of skin into which the nostrils open; mainly seen on hawks and falcons; often brightly colored. Common call type given by many passerines, often in alarm. Species that migrates around the Gulf of Mexico rather than flying across it. Gradual change in coloration or morphology across a geographic area. An elaborate and protracted vocalization including elements of typical songs as well as other highly varied notes and phrases, sometimes mimicry. See flight call. Relatively small feathers covering the bases of flight feathers (primaries, secondaries, tertials, and rectrices). The upper ridge on a bird’s bill. Slightly more elaborate and stereotyped version of song given at dawn and often dusk in some species (e.g., flycatchers). Having the wings tilted up in a shallow V shape while gliding; aids in stability, particularly in windy conditions. For general queries, contact info@press.princeton.edu.

edge habitat elliptical migration route eye-arcs eyering facultative filoplume flight call

gape glide gonydeal angle gular hybrid immature intergrade irruption

juvenile lek leucistic lore(s) malar mandible mangroves maxilla mesic mid-story mirror mixed-species flock molt cycle monotypic morph

Abrupt or transitional boundary between forest and field habitats. Migration pattern in which migrants move north on a more westerly route, and south on a more easterly route. An eyering that is broadly broken front and back, with wider separation than a broken eyering. Ring of light-colored feathering encircling the eye; referred to as a broken eyering if narrowly broken front or back. Describes migration in response to environmental conditions (e.g., cold weather, snow cover, drought, etc.) rather than on a fixed seasonal schedule. A specialized, hairlike feather that acts as a sensory organ, helping birds monitor the movement and position of their main feathers, particularly those used in flight. Common call type given by many species, primarily to maintain contact with other birds; given primarily in flight by many waterbirds (shorebirds, herons, etc.) but given equally in flight and while perched by many passerines; also given in nocturnal migration by many species (= nocturnal flight call). Also known as contact call. The fleshy back corner of the mouth; may protrude inward in a longer line (gape line) or only slightly (gape notch). Direct flight during periods without flapping; many larger birds (e.g., raptors, seabirds) exhibit longer glides with wings open, while most passerines exhibit much shorter glides with wings closed. A bump along the bottom edge of the lower mandible where two plates meet; visible in only some groups of birds (e.g., gulls). Throat. The offspring of 2 different species (e.g., Canada Goose × Greater White-fronted Goose). Any bird that is not an adult; some species undergo several different immature plumages, sometimes over multiple years, before reaching adult plumage. The offspring of 2 different subspecies (e.g., Red-shafted × Yellow-shafted Flicker). Large-scale fall migration, typically by northern species, into areas well beyond their normal winter range; typically in response to food shortages in normal range (e.g., many finches) but sometimes in response to an overabundance of food on the breeding grounds, resulting in higher productivity (e.g., Snowy Owls). An immature bird wearing its first coat of non-downy feathers after hatching. A gathering of birds (e.g., some grouse) where males display and compete with each other to attract and mate with females. Lek also refers to the gathering ground itself. A mutation causing partial loss of pigmentation, resulting in white or pale feathers, typically retaining normal-colored eyes. The area between a bird’s eye and the base of its bill; dark lores or pale lores can greatly influence facial expression. Group of feathers between the throat and cheek behind the lower mandible. The lower half of the bill; often called lower mandible. Specialized plant community permanently or periodically inundated with salt or brackish water; can be low and scrubby or tall and forest-like; some species have stilt roots. The upper half of the bill; often called upper mandible. Describes a relatively wet habitat. The middle layer of vegetation below a forest canopy. Typically used in gulls to refer to a white patch near the tip of the outer primaries. A cohesive, usually foraging flock of birds containing multiple species moving through vegetation (e.g., forest canopy); often includes both migrant and resident species. The period between the repetition of a given molt, usually a year and usually referring to the basic molt cycle, i.e., the period between the start of one prebasic molt and the next prebasic molt (see “Molt and Aging”). A taxonomic group with only one member. A distinct, genetically determined color variation within a species; sometimes incorrectly referred to as a “phase.”

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nectaring orbital ring overslurred passerine patagium/ patagial mark peep pelagic pinnae pinyon-juniper woodland pishing primaries primary projection

Actively feeding on flowers or hummingbird feeders. Ring of bare skin encircling the eye; generally noticeable only when brightly colored. Describes a note that smoothly rises up then back down in pitch; overslurs may be brief and sharp, as in píp, or drawn out, as in peEEEer. A perching bird in the order Passeriformes. Membrane of skin along the leading edge of the wing between the “shoulder” and “wrist.” A well-known field mark for Red-tailed Hawk is the bar of dark feathering in this area. Any of the smaller sandpipers in the genus Calidris. Offshore, deeper marine waters beyond the continental shelf; pelagic trips are ventures offshore in boats to seek oceanic birds not normally seen from land. Ear tufts. A biome in the arid, mid-elevation regions of the West, defined by pinyon pines (Pinus sp) and junipers (Juniperus sp). Attracting birds by imitating scolding songbirds (e.g., Tufted Titmouse). Flight feathers on the outer portion of the wing (the “hand”); most birds have 10 primaries, though the outermost (10th) primary is very short in most songbirds. Distance that the primaries project past the tertial tips on the folded wing; can be a useful field mark to help distinguish similar species in many bird groups, particularly shorebirds and flycatchers. Tail feathers.

rectrices (singular, rectrix) remiges Flight feathers on the wing, including primaries, secondaries, and tertials. rictal bristles Hair-like feathers at the base of a bird’s bill that aid in food capture. riparian Ecosystem along streams and rivers, including forests and seasonal wetlands. sally Hunting technique wherein a bird flies from a perch to catch insects in the air, often returning to the same perch; employed by many flycatchers, warblers, and others. scapulars “Shoulder” feathers, covering the area where a bird’s body meets the wing on the dorsal surface; on many waterbirds and raptors, these are relatively large feathers with easy-to-see patterns. scold Varied harsh, raspy mews or chatters given by some species of songbirds (e.g., wrens, titmice, vireos), often in alarm. secondaries Flight feathers on the middle portion of the wing (the “arm”); number of secondaries varies by wing length, from as few as 6 on hummingbirds to as many as 30+ on albatrosses. second growth A forest or woodland area that is regenerating after being cleared by fire or cutting; generally refers to younger stages of growth. sibilant With a hissing quality. skylarking The act of singing in display flight, named for this well-known behavior in Eurasian Skylark. song Usually the most elaborate bird vocalizations, used to advertise to a potential mate or to defend a territory from a rival; sung mainly in the breeding season (but year-round in some species, particularly year-round residents); given mainly by males, though females also sing in many species. Note that in many groups of birds (e.g., warblers), songs given early or late in the season are often softer and less well-defined (see subsong). species complex A group of closely related, recently evolved species that are nearly identical in appearance; species boundaries are often unclear. spectacles Pale eyering combined with a pale supraloral stripe, creating the look of eyeglasses or spectacles. spectrogram Visual representation of a sound, showing frequency on the vertical axis and time on the horizontal axis; variations in darkness reflect amplitude (loudness). speculum Iridescent panel on the upper surface of the secondaries in various duck species. stoop Behavior when an airborne raptor tucks its wings and descends rapidly in pursuit of prey. stopover site A location with good habitat and abundant food resources where migrating birds stop to rest and refuel before continuing; duration of stop varies from hours to several weeks, depending on the bird’s needs as well as weather conditions. subadult Generic term for older immatures that are nearing adult appearance.

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subsong

Bird song that is softer and less well defined than the usual territorial song; given by immatures just learning to sing and sometimes by adults, particularly early or late in the season; sometimes heard only at close quarters as a quiet warbling. subspecies A geographically distinct breeding population within a species showing consistent differences in appearance (plumage/measurements) or voice from other members of that species; subspecies typically interbreed freely where they meet. subspecies group A field-identifiable group of subspecies that share similar visual or vocal characteristics; a subspecies group can be polytypic (containing multiple subspecies), or monotypic (containing 1 subspecies). superspecies A group of similar species that share a common ancestor; typically largely allopatric. supraloral Front part of the eyebrow, above the lores. sympatric Occurring within the same geographical area; overlapping in distribution. taiga See boreal forest. tertials Flight feathers on the inner portion of the wing (humerus); on many species, these are longer feathers that function to protect the primaries when the wing is folded. tongue In the context of gull wings, a pale extension on the inner web of the primaries into the dark wingtip. trans-Gulf Species that migrates directly across the Gulf of Mexico. migrant tubercule Warty protuberance on the facial skin (e.g., Turkey Vulture). tundra Coldest biome, characterized by barren, treeless landscape with dwarf shrubs, sedges, mosses; found in both Arctic and alpine regions. Type A song The primary advertising song of a male warbler, sung primarily toward females; often with an accented ending; often more stereotyped (same song type repeated); often sung all day until a mate is found. Type B song A warbler song sung primarily by males toward rival males; often with unaccented endings; often more variable or alternated with other songs; sung more at dawn, dusk, and later in the season; often accompanied by chips. underslurred Describes a note that smoothly descends then rises upward in pitch. understory The lower layer of vegetation growing near the ground, beneath the mid-story and canopy of a forest or woodland. upslurred Describes a note that rises smoothly upward in pitch. vent Feathering between the belly and the undertail coverts covering the cloaca. “wrist” Joint between outer wing (“hand”) and inner wing (“arm”).

Geographic Terms Aleutian Islands Chain of volcanic islands extending west from Alaska toward Russia; separates Bering Sea from Pacific Ocean. Amazon basin The part of South America drained by the Amazon River and its tributaries. Appalachians Large mountain system located in eastern North America stretching from New Brunswick to Alabama. Arctic Region above the Arctic Circle. Atlantic Canada Easternmost region of Canada including New Brunswick, Newfoundland and Labrador, Nova Scotia, and Prince Edward Island. Baja California The Baja California peninsula, including the states of Baja California and Baja California Sur. cen. US Generally, the region east of the Rockies to the Midwest (west of the Appalachians). circumpolar Describes a species distribution that extends all the way around the globe at high latitudes. East Generally, the region east of the Great Plains. Edwards Plateau An uplifted geographic region in west-central Texas. Eurasia The combined continental landmasses of Europe and Asia.

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Great Basin Great Plains Greater Antilles High/Low Arctic Interior West Lesser Antilles

Macaronesia Mid-Atlantic Midwest Neotropics New World North Northeast Northwest Oceania Old World Pacific NW Pacific Slope Pribilof Islands Rockies/Rocky Mts South Southeast Southwest subarctic West

An arid, closed desert basin of alternating valleys and mountains in the western United States characterized by distinct hydrology and flora and fauna adapted to its dry, temperate desert environment. Large geographic region of grasslands and prairies east of the Rockies and generally west of the 100th meridian, stretching from southern Canada through central Texas. A grouping of the larger islands in the Caribbean Sea, including Cuba, Hispaniola, Puerto Rico, and Jamaica, together with Navassa Island and the Cayman Islands. Broad habitat types in the Arctic and subarctic regions. High Arctic (i.e., at high latitudes) is farther north and characterized by sparse or no vegetation; Low Arctic is farther south and characterized by extensive tundra vegetation. The region encompassing vast areas of habitat from the Rocky Mountains west to the Sierra Nevada (California) and the Cascade Range (British Columbia to Oregon). A grouping of Caribbean islands that forms an arc beginning east of Puerto Rico at the archipelago of the Virgin Islands, swings southeast through the Leeward and Windward Islands toward South America, and turns westward through the Leeward Antilles (Aruba, Bonaire, and Curaçao) along the Venezuelan coast. A group of four volcanic island groups (Azores, Madeira, Canary Islands, and Cape Verde) in the North Atlantic off the coasts of Europe and northern Africa. Generally, the coastal zone of the United States from New York to the Outer Banks, NC. Generally, the region of the northern United States west of the Appalachian Mountains stretching west to the 100th meridian (the eastern edge of the Great Plains). New World tropical regions. North, Central, and South America as well as the Caribbean. Generally includes Canada and northern regions of the United States. A region comprising the states of Connecticut, Maine, Massachusetts, New Hampshire, New Jersey, New York, Pennsylvania, Rhode Island, and Vermont; abbreviated as the NE. A region comprising British Columbia, Alberta, Washington, Oregon, Idaho, Montana, and Wyoming; abbreviated as the NW. A geographic region in the Pacific Ocean encompassing Australia, New Zealand, and thousands of smaller islands. Africa, Asia, Europe, and Australia. Loosely defined geographic region encompassing Oregon, Washington, and Idaho, as well as British Columbia; characterized by a cool, damp climate. The region of the West from the Continental Divide to the Pacific Ocean. A group of four volcanic islands in the Bering Sea, about 500 km off the coast of mainland Alaska. The major mountain range bordering the western edge of the Great Plains stretching over 4,800 km from northern British Columbia to New Mexico The region south of Pennsylvania and the Ohio River, and west to Oklahoma and Texas. The region of the southeastern United States reaching north to Maryland and West Virginia, and stretching west to Arkansas and Louisiana; abbreviated as the SE. Loosely defined geographic region of the United States that includes Arizona and New Mexico, along with adjacent portions of California, Colorado, Nevada, Oklahoma, Texas, and Utah; characterized by a hot, arid climate; abbreviated as the SW. Region immediately south of the Arctic Circle. Broadly refers to the western United States west of the Great Plains and south of Canada.

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Bird Topography

Most terms we use should be self-explanatory, especially in reference to the plates, but some of the more important and potentially unfamiliar terms are illustrated below (see also the glossary “Bird-related Terminology”). Note how the same tracts of feathers can appear different in different groups of birds. lateral crown stripe eyebrow

upper mandible

lores central crown stripe

eyeline

eye-arcs

eyering

supraloral

mustache

lower mandible

malar throat stripe

mantle lines

median coverts greater coverts tertials

MacGillivray’s Warbler

Nashville Warbler

alula primary coverts crown nape

tail

mantle

Savannah Sparrow

secondaries

forehead

scapulars

primaries

throat cheek

rump uppertail coverts

breast wingbars

undertail coverts

P8 P9 P10

primary coverts

P6 P5

vent

Northern Shoveler

alula

P4 P3 P2

belly

Magnolia Warbler

P7 primaries (numbered from innermost to outermost)

flank

secondary coverts median

greater P1

lesser

secondaries underwing coverts tertials tail nape

axillars

uppertail rump coverts

mantle

scapulars tertials lesser coverts primaries median coverts greater coverts tail

undertail coverts

Ring-billed Gull

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Molt and Aging

Feathers define birds. When we look at a bird, most of what we see is feathers—those remarkable lightweight structures that have evolved to cover and protect a bird, provide colors and patterns for courtship and camouflage, and allow it to fly. Feathers are not permanent structures, however—they wear out from day-to-day exposure to the elements and need to be replaced, usually once a year. Molt is simply feather growth (thus, loss or shedding of feathers is a passive by-product of the process). Yet, molt is also one of the most important aspects of any bird’s life history: no molt = no feathers = no bird. We will first look at why and when molt happens over the course of a bird’s life, and then look at how to describe the different plumages a bird wears in its life.

Timing and Extent of Molts All else being equal, all birds grow a full coat of new feathers (i.e., undergo a complete molt) once a year, starting with the acquisition of juvenile plumage (their first full coat of non-downy feathers after hatching from the egg with variable amounts of down or, in some species, hatching naked). Juvenile plumage varies from rather weak and soft (in species such as passerines, in which it is grown quickly to help them escape the vulnerability of the nest) to relatively strong and durable (in species such as raptors or petrels, which have protracted nestling periods with few or no predators). Because all of a bird’s juvenile plumage grows in at the same time, it typically appears uniformly neat and fresh in late summer and fall, often in striking contrast to the worn plumage of adults at the end of their breeding season. In many species, especially passerines, juvenile plumage looks obviously different from adult plumage; in others, mainly larger species, it can look almost identical to adult plumage. Species with relatively strong juvenile plumage can survive their first year without any additional molt. But species with relatively weak juvenile plumage undergo a unique molt (i.e., one with no counterpart in later years) within a few months of fledging, replacing juvenile feathers that would not last a whole year. This molt can be very rapid, taking only 1–2 weeks, such that juvenile head and body plumage is held briefly and rarely seen (as with many warblers), or it can be protracted over a few months (as with some shorebirds). In many species, including most passerines, the plumage attained by this molt resembles adult plumage. Although this novel first-year molt usually involves just head and body feathers, which are less costly and less time-consuming to molt than flight feathers (the primaries, secondaries, and tail feathers), it can be highly variable in extent between and even within species. For example, House Finches hatched from an early-season first brood in southern California may undergo a complete molt over the long, sunny summer months after fledging, whereas House Finches from a late brood in New England may only have time to replace head and body feathers before the onset of winter. Once a bird has survived its first year, it enters a stereotyped annual pattern of repeated molts for the rest of its life. Where and when molts occur depend largely on where and when the most reliable food sources can be found. Many species molt on or near their breeding grounds in late summer, when food is plentiful. Others (particularly those breeding in regions where late-summer food sources are scarce) migrate long distances before molting, either to their nonbreeding grounds or to stopover sites that offer sufficient fuel for their molt. Many species, such as smaller hawks and crows, simply have 1 complete molt annually, and the complete annual molt takes anywhere from 2–3 weeks in some passerines to 4–5 months in some larger birds. Other species, such as most shorebirds and many warblers, have a 2nd (and rarely a 3rd) molt added into their annual cycle. These extra molts reflect the need to replace feathers that become worn thanks to life-cycle characteristics such as long-distance migration, which exposes plumage to strong sunlight year-round. As with novel 1st-year molts, because of the energy and time needed to grow new flight feathers, added molts in the adult cycle also usually involve only head and body feathers, and often wing coverts; such molts can proceed fairly rapidly, within a few weeks, and usually occur in the late winter and early spring, prior to migration, resulting in fresh breeding plumage (e.g., in many spring-migrant passerines and shorebirds). Learning to see contrasts (often subtle) between newer and older feathers attained by different molts can help determine the age of a bird and also help with species identification.

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Naming Molts and Plumages

There are 2 main systems for naming molts and plumages. One is the system we use in this book (often known as the life-year system), with terms such as 1st-year, 2nd-year, juvenile plumage, female plumage, breeding plumage, and so on, whereby the color and pattern of feathers convey information relating to the bird’s age, sex, and seasonal or breeding status. The other system, proposed in 1959 by ornithologists Phil Humphrey and Ken Parkes (thus known as the Humphrey-Parkes or H-P system) and modified in 2003 by Steve N. G. Howell and colleagues, is based on patterns of feather replacement (regardless of the bird’s age or sex) and on how molts have evolved within avian lineages. The H-P system is of less practical use in popular birding parlance, but it is nonetheless helpful for birders to better understand how molt patterns relate to a bird’s appearance. It is also important to not equate H-P terms with life-year terms (as many birders and field guides mistakenly do), as they have different bases of definition and are not synonyms; the former relates to molt patterns while the latter relates to the bird itself. In the H-P system, the only thing that matters is the number of molts that occur in an annual cycle— the color and pattern of plumage is irrelevant. There is always a one-to-one relationship between molts and plumages in the H-P system (thus, only a molt produces a plumage), whereas in the life-year system, “nonbreeding plumage” and “breeding plumage” can look quite different, but the change in appearance may be brought about by wear and fading of the feathers, not necessarily by molt. Thus, 2 life-year “plumages” can equate to only a single H-P “plumage.” Conversely, because there may be 2 molts in an annual cycle but no change in appearance, the H-P system uses 2 different terms for these plumages, whereas the life-year system would not distinguish them, and a bird would, for example, simply wear its “adult plumage” year-round. See examples below. The modified H-P system has helped reveal that—despite the seemingly bewildering complexity of molts and plumages across more than 11,000 species worldwide—only 4 underlying molt strategies are involved, as shown on the following pages (H-P terms capitalized).

Snow Bunting

nonbreeding ♂

breeding ♂

Basic Plumage (fresh)

Basic Plumage (worn)

Savannah Sparrow adult

adult

Basic Plumage

Alternate Plumage

Examples of life-year (italic) and H-P (non-italic) terminology. Seasonal change in ♂ Snow Bunting comes about by wear and fading, not molt, whereas 2 annual molts in Savannah Sparrow produce no appreciable change in appearance. For general queries, contact info@press.princeton.edu.

Simple Basic Strategy. Only 1 molt (and plumage) in every cycle (the Prebasic Molt, producing Basic Plumage), starting with a strong juvenile plumage (also known as 1st Basic Plumage) that carries a bird through its first year. Uncommon; found only in non-passerines. Northern Fulmar

Red-tailed Hawk

complete molt

incomplete or complete molt

juvenile (1st Basic Plumage)

adult (2nd and later Basic Plumages)

juvenile (1st Basic Plumage)

Complex Basic Strategy. Only 1 molt in the adult cycle (Prebasic, producing Basic Plumage) but with a novel molt added into the 1st cycle (the Preformative Molt, producing Formative Plumage), replacing a variable amount of weak juvenile plumage. The most common molting strategy among modern birds, both non-passerines and passerines. Blue Jay

molt contrast complete molt

partial molt

retained juvenile coverts

adult (2nd and later Basic Plumages)

1st-winter (Formative Plumage)

juvenile (1st Basic Plumage)

House Sparrow adult

adult

♀

fading and wear complete molt juvenile (sexes similar) (1st Basic Plumage)

nonbreeding

♂

breeding

♂

adult (Formative and subsequent Basic Plumages)

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Simple Alternate Strategy. Two molts (and plumages) in all cycles (a Prealternate Molt—usually partial—producing Alternate Plumage alternates with the complete Prebasic Molt). Infrequent, only in non-passerines, and best documented in Larus gulls. Ring-billed Gull

partial molt

fading and wear

juvenile (1st Basic Plumage)

1st-winter

1st-summer (1st Alternate Plumage)

2nd-winter (2nd Basic Plumage) complete molt

partial molt

2nd-summer (2nd Alternate Plumage)

complete molt

partial molt

adult breeding (3rd and later Alternate Plumages) adult nonbreeding (3rd and later Basic Plumages)

Complex Alternate Strategy. Two (rarely 3) molts in all cycles (complete Prebasic, partial Prealternate, and sometimes a partial Presupplemental molt, which produces Supplemental Plumage), plus a novel (Preformative) molt in the 1st cycle. Fairly common in both non-passerines and passerines. Examples of 2 and 3 annual molts follow. In many passerines, post-juvenile 1st-year plumages resemble adult plumage, but juvenile flight feathers, alula, and primary coverts are retained, becoming relatively worn and faded compared to fresher Formative and Alternate feathers, often allowing age to be determined.

Yellow-rumped Warbler (Myrtle) (♂s) partial molt

partial molt

juvenile (1st Basic Plumage)

1st-winter (Formative Plumage)

1st-summer (1st Alternate Plumage)

complete molt

nonbreeding adult (2nd and later Basic Plumages)

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partial molt

breeding adult (2nd and later Alternate Plumages)

Some ducks undergo 3 molts per year. Post-juvenile 1st-year plumages resemble adult plumage, but juvenile wings and often some (worn and faded) juvenile tail feathers are retained. Notably, the bird’s outward appearance does not necessarily change with a molt (cf. Savannah Sparrow, p. 19). Perhaps confusingly, appearances (but not molts) can differ between males and females, reflecting different life-history pressures. In males, Alternate Plumage resembles Formative and adult Basic; an extra Supplemental Plumage is cryptic (“eclipse” plumage), providing camouflage while birds are flightless in wing molt. In females, Alternate Plumage differs from Formative and adult Basic in tertial pattern (more cryptic for nesting), but Supplemental Plumage looks much like Alternate. Mallard

1st-year ♀ nesting/eclipse (1st Alternate & 1st Supplemental Plumages)

1st-year ♀ courtship (Formative Plumage)

partial molt

juvenile (1st Basic Plumage)

complete molt

1st-year ♂ courtship/breeding (Formative & 1st Alternate Plumages) partial molt

partial molt

adult ♂ courtship/breeding (2nd and later Basic & Alternate Plumages)

1st-year ♂ eclipse (1st Supplemental Plumage)

adult ♂ eclipse (2nd and later Supplemental Plumages)

Identifying Birds You walk into your favorite coffee shop and immediately notice a few of your friends. You know their names, you know where they live, what they do for a living, what their voices sound like. You didn’t go through a list of field marks to identify them; you just knew who they were—you recognized them. In fact, we can recognize hundreds, maybe thousands, of different people just through our passive exposure to them in life, on TV, in movie theaters. Our ability to distinguish people so easily can be extended to almost any facet of the natural world. All it takes is focusing some of your attention in that direction. Identifying birds in the field is both an art and a science, a blending of observation and experience combined with reference to resources such as this field guide. Learning to recognize some of your local birds and using them as building blocks to learn more is a key starting point.

Always Mind Your Surroundings This is a good philosophy for life in general, but in birding it matters a lot. Every species of bird has specific habitat preferences and a certain range where it occurs, which may vary dramatically by season. Even migration times can be fairly specific. For example, a nighthawk in California in April is a Lesser Nighthawk; a spot-breasted thrush (genus Catharus) in New York in mid-April is almost certainly a Hermit Thrush; and a small “ladder-backed” woodpecker in oak woodland in California (at any season) is a Nuttall’s Woodpecker. Knowing when birds are likely to occur in a particular region, and in what habitat they are likely to be found, is critical for bird identification. Yes, birds can show up out of range, but for almost all species that doesn’t happen often enough to worry about. 22

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What to Look For?

When you see an unfamiliar bird, it is so easy, basic human nature in fact, to focus just on color and anything “different” that stands out. “I saw a dull brown bird with some white in the tail. What was it?” Although this information can be helpful in identifying the bird, a lot of other things that you saw but didn’t specifically or consciously notice may be as or more helpful. In fact, with no context, this description could fit a pipit, a sparrow, a longspur, a meadowlark, a sandpiper, a Mourning Dove, or even a Roughlegged Hawk! Don’t overlook the obvious, such as relative size (there’s a big difference in size between a pipit and a hawk, for example) and structure (shape and proportions). Does it have long legs, a long neck, and a spiky bill like a heron? Does it have short legs, a longish tail, and a conical bill like a sparrow? Sometimes behavior is just as important to bird identification as size and structure. What is the bird doing? Is it sitting still and upright on a branch, then sallying out for insects (a flycatcher) or hopping sluggishly through foliage with occasional flutters (a vireo)? Is it in a pond picking at the water surface (a yellowlegs) or probing persistently with its bill and face in the water (a dowitcher)? Of course, paying attention to details such as plumage patterns, bill color, leg color, and eye color can also be critical to identification. Becoming familiar with the basics of bird topography and molt patterns is important for understanding these details, so spending a little time reviewing that material can be extremely helpful.

What to Listen For? Listening to bird sounds adds an entire dimension to the birding experience. In addition to the aesthetic appeal of listening to natural sounds, bird sounds can be extremely helpful in locating birds, can allow quick identification of unseen birds, and can be critical to identifying some birds even when seen well. Learning bird sounds—learning to notice details of pattern, pitch, and quality—is something that comes with time, like learning a language. Tools such as the Merlin app can help speed up the process, but nothing beats time in the field. However, even to the untrained ear, some bird sounds are quite distinctive, or at least obviously different from the sounds that a similar-looking bird makes.

Understanding Limitations and Variation Experienced birders know that sometimes, birds are best left as unidentified. Every time you go out in the field, there will be birds you can’t identify. Most often, this will be simply because you didn’t see them well enough. Although it may seem obvious, it is important to realize that lighting and distance can affect what you think you see. Consider how light is warmer in early morning and late afternoon, and how harsh light can dramatically affect the appearance of colors and patterns. Also consider how patterns you think you see at a distance may look different up close. For example, the white undertail coverts on a Cooper’s Hawk may appear to be on the rump when viewed at a distance, inviting confusion with Northern Harrier. It is also important to consider variation. Just as with people, every bird is different, and all species exhibit some level of variation in appearance. Variation ranges from minimal and unlikely to affect species identification (e.g., in crows and chickadees) to extensive and potentially bewildering (e.g., in immature gulls). Variation in appearance exhibited by birds can be broken down into 3 categories: life history variation (reflecting age, sex, and season), geographic variation, and plain old individual variation. Thankfully, not all groups of birds show every kind of variation. Moreover, patterns of variation are often the same across most species within a family. For example, gulls and loons have different age and seasonal plumages but no sex differences in plumage, and loons show no geographic variation. Flycatchers exhibit some age-related variation but no striking seasonal plumage variation, and in only one North American flycatcher species do the sexes look obviously different. Storm-petrels look basically the same regardless of age, sex, or season. Becoming familiar with such family- or group-wide patterns can make identification much easier by reducing the possibilities to consider. The thorniest problem is individual variation. Birds will rarely show aberrant plumages resulting from melanism (an excess of dark pigment, so birds look unusually dark) or leucism (reduced pigment, so birds look washed out or have patches of white). Much more common is variation in overall brightness, particularly in yellow to red tones, sometimes related to diet or to hormone levels while molting. One of the greatest issues with individual variation in birds relates to how plumage patterns can be affected by wear and fading. Wear is the physical deterioration of a feather; fading is color loss through exposure to sunlight; and the two processes often work together to cause appreciable changes in how a For general queries, contact info@press.princeton.edu.

bird looks. In general, birds tend to be most worn and faded in late summer and early fall, before their complete molt. And birds that live in open scrubby habitats tend to become more faded than birds living in shadier, more protected forest habitats. Pale feather edgings can wear away, creating a darker overall appearance (as in a Northern Mockingbird losing its wingbars in late summer), or feathers can fade overall, creating an appreciably paler appearance (as in a bleached-out immature American Herring Gull in summer). It is interesting to note that in some cases, plumage wear can change a bird’s appearance drastically, as with nonbreeding and breeding male Snow Buntings—no molt is involved, just the wearing off of buffy-brown feather tips that veil a striking underlying black-and-white pattern. Books could be written on how to approach the process of bird identification—indeed, several have been. For those interested in delving more deeply into this topic, we recommend two carefully thoughtout books written by experienced birders with the aim of helping anyone understand the identification process: Sibley’s Birding Basics (Sibley 2002) and the Peterson Guide to Bird Identification—in 12 Steps (Howell & Sullivan 2018).

Cornell Lab of Ornithology Science to Conservation Action, Powered by Birders If you’ve ever stepped outside at dawn and heard the first birds start singing, you know the feeling: the world is waking up, sound by sound. Birding begins there—with attention and curiosity. A song you recognize instantly. A call you just can’t place. A flash of colorful wings that makes you stop in your tracks. Birds pull us outdoors, sharpen our senses, and connect us to the living world in a way that’s both deeply personal and surprisingly universal. The Cornell Lab of Ornithology, based at Cornell University in Ithaca, New York, exists to promote that connection and to turn it into a powerful tool for conservation. The Lab is a nonprofit organization and global leader in bird science and conservation, bringing together researchers, technologists, educators, and the global birding community. Our work is driven by a simple idea: by better understanding birds, we can better protect biodiversity and human well-being. Bird populations around the world are under extraordinary pressure. Habitat loss, climate change, pesticides, collisions with human-built structures, and many other threats are taking a significant toll. In the United States and Canada alone, we’ve lost more than 3 billion birds in the past 50 years—nearly 1 out of 3. That number is sobering, but it’s also motivating: it tells us we need better information, better tools, and better coordination to move the needle for conservation. We’re not only trying to learn what’s happening to birds—we’re working to make that knowledge useful, accessible, and actionable for birders, scientists, and conservation decision-makers.

eBird: The Global Birding Network That Became a Conservation Engine At one level, eBird is wonderfully simple: it’s a free set of tools to record what birds you saw (and heard), where and when you were birding. It keeps your life list, your year list, your county list. It tracks your personal milestones. It helps you plan what birds to look for next and keeps you connected to what others are finding around you. But eBird is also something much bigger. Thanks to birders, eBird has become one of the world’s largest biodiversity projects, with observations contributed from every country and for just about every species. It is a living record of bird occurrence through time—millions of checklists and billions of bird observations, plus photos, sounds, and videos. It’s a vast record of global birdlife, constantly growing as people head out into the field each day. What makes eBird especially powerful is its checklist design. A checklist is not just a list of birds—it is a snapshot of a birding event: a place, a date, and the effort involved (how long you birded, how far you traveled, whether you were stationary or traveling). Automated filters and dedicated volunteer eBird reviewers help verify unusual sightings. This structure helps turn everyday birding into data that scientists can work with at scale, accounting for variation in effort, detectability, and other factors to reveal bird distributions, abundance, and changes through time. Every photo or recording submitted with a checklist is automatically curated as a scientific specimen in the Lab’s Macaulay Library. This permanent archive of bird behavior is an endless source of inspiration, exploration, and technological innovation. The millions of sounds contributed by eBirders help power automated sound identification for bioacoustics tools that are helping to protect species and habitats 24

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Relative abundance of Wilson’s Warbler based on eBird Status and Trends data.

around the world—and to teach and inspire millions of people through tools like the Merlin Bird ID app. All of this means your birding can contribute to conservation without you having to “do anything extra.” Just go birding. Submit your data using the free eBird mobile app, and your observations will join a vast dataset that helps answer urgent questions such as: • Where are birds throughout the year, including migratory connectivity across countries? • Which places consistently matter the most for birds, and when? • How are species shifting as climate and habitats change? • Where are populations increasing or declining, and how quickly? • How can limited conservation resources be used for the greatest impact? These are not abstract questions. They determine where we protect habitat, where we restore it, how we prioritize flyways, and how we measure whether conservation actions are working. For birders, eBird also helps you pay attention more carefully in nature. It turns an everyday walk into a more meaningful record. It teaches you what birds are expected for a place and season—and what’s unusual. It makes you ask, “Did I miss anything?” And over time, it helps you to become a better birder.

Merlin Bird ID: Learning Birds by Sound and Sight, with Confidence Most of the time, you hear a bird before you see it. That’s why Merlin Bird ID has been so transformative. Merlin is a free mobile app created by the Cornell Lab to help people learn to identify birds and open up a world of information and experiences in the outdoors. Whether you’re just starting out or you’ve been birding for decades, Merlin is like having a helpful friend in your pocket—one who can listen with you and offer helpful identification suggestions when you need them. Merlin gives birders multiple ways to identify a bird: • Sound ID: record the sound around you, and Merlin identifies birds in real time • Photo ID: upload a photo, and Merlin suggests the most likely matches • Step-by-step ID: answer a few questions about size, colors, and location • Explore Birds Nearby: see which species are likely right now wherever you are For general queries, contact info@press.princeton.edu.

Sound ID offers a whole new dimension for connecting people with birds. For new birders, it shortens the learning curve dramatically for birding by ear. For experienced birders, it can be a fast confirmation tool, or a way to detect background species you might not have noticed while tracking a bird in your binoculars. But Merlin’s real power isn’t just identification—it’s participation. When someone can put a name to the sound in the trees, they are more likely to keep asking questions, more likely to care, and more likely to return to bird again. In the long run, that matters deeply. The future of conservation depends on bringing more people into nature—not only as observers but as advocates for the places birds need. In that way, Merlin isn’t just an app. It’s an open door to knowing and appreciating the natural world.

Birds of the World: A Deep Dive into the Lives of Birds Knowing the name of a bird is only the beginning. That’s where Birds of the World comes in. It’s the most comprehensive and trusted resource for information on avian life histories—covering identification, vocalizations, habitat, behavior, breeding, diet, conservation status, and more, for all bird species and families. Birds of the World supports everyone from backyard birders to professional ornithologists because it is built on decades of published research, expert knowledge, and carefully curated media. If Merlin helps you identify a bird, and eBird helps you record it, Birds of the World helps you understand it. And understanding is what turns birding into something richer: not just a list, but a relationship.

Why These Tools Matter At the Cornell Lab, we think about bird conservation at the scale birds live their lives: across landscapes, across seasons, and across borders. That requires both high-quality information and a worldwide community of people paying attention. eBird, Merlin, and Birds of the World are each powerful on their own. Together, they form a loop: • Merlin helps people identify birds by sight and sound • Birds of the World helps people learn and go deeper • eBird helps people share what they find and reveal patterns at scale • Those patterns become science and decision-support tools used in conservation It’s a modern conservation model: open, collaborative, and driven by both technology and people. The Lab is home to a suite of other resources that birders will find useful: BirdCast uses weather radar and migration models to forecast bird migration in near real time. It helps birders and conservationists understand when and where birds are moving—especially during peak migration nights. Bird Cams bring birds to life through live-streaming cameras from nests and wild places around the world, offering an up-close view of bird behavior and helping people connect with birds through learning, wonder, and daily observation. NestWatch is a community science program that invites people to monitor bird nests and share what they observe. These data help researchers track breeding success and study how birds respond to environmental change over time. Bird Academy is the Cornell Lab’s online education platform, offering engaging courses that help people build bird identification skills and learn more about bird biology and conservation. It’s designed for everyone from curious beginners to experienced birders who want to go deeper. Living Bird is the Lab’s magazine for supporting members, filled with beautiful photography and multimedia, insightful articles about birds and conservation, and tips for enjoying and learning about birds. Explore all of these and more on the Lab’s website, AllAboutBirds.org.

A Shared Invitation

This field guide is part of the same story: the idea that birds can change how we see the world—and that paying attention can become a form of stewardship. So bring your binoculars and camera. Listen carefully. Learn the songs. Follow curiosity where it leads you. And we encourage you to join the global community of people helping build the knowledge to protect and restore birds and their habitats. Because when we listen closely enough—across yards, forests, wetlands, and flyways—birds are always telling us something. And today, that story matters more than ever. For general queries, contact info@press.princeton.edu.

Species Accounts

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Snow Goose Anser caerulescens L 65–84cm, Wt 2.5–3.6kg. Abundant goose at colonial nesting areas on Arctic tundra, favored wintering sites, and migration flyways. Flocks of 1000s fly between fields used for foraging and roosting sites in marshes, lakes, and estuaries. Atlantic birds average larger than interior birds, with longer, more massive bill and very prominent grin patch, but considerable variation and intergradation complicates ID of single birds. White morph common in all populations. Dark morph, “Blue Goose,” most common in e.-cen. US and Canada, particularly the Mississippi River valley and the Gulf Coast of LA and TX, is uncommon in the West and rare in Atlantic birds, where most are likely intergrades. ♂ averages larger with larger bill than ♀. Juv dark morph very dark overall with dark bill and legs. 1st-yr appears dirty, retaining at least some dingy feathers into Apr. Sounds: Often detected in migration by call, a nasal, hoarse fairly high owk owk or lower whouk whouk; lacks the more musical honking quality of Canada Goose. Atlantic averages lower-pitched and more resonant than other populations. Status: Common. Migration mainly late Feb–Apr, Oct–Dec. Northern extent of winter range varies with availability of feeding and roosting areas. Winters to n. Mexico. intermediate

deep black grin patch almond-shaped eyes

Snow larger individual, mainly Atlantic

Snow

thicker bill, more curved at base than Ross’s

Snow × Ross’s hybrid

tall, rounded head

Ross’s

round eyes

eye close to bill base

Ross’s

small triangular bill

Ross’s Goose Anser rossii L 53–66cm, Wt 1.2–1.6kg. A “cute,” smaller, and more local cousin of the Snow Goose. From Snow by smaller and shorter bill that meets face in straight line, more rounded head, and very narrow grin patch. Bluish warty patch on bill base most developed in older ads. Juv differs from Snow in having far fewer dingy markings; distinction less useful by Mar when many Snows have replaced many juv feathers. Hybridizes regularly with Snow. Dark-morph Ross’s rare; many putative dark morphs are hybrids with Snow. In flight, note Ross’s short neck and quicker wingbeats. Presence in large flock of flying Snows is sometimes revealed by slightly different spacing; also more likely to be near ends of V. Sounds: Much less vocal than Snow; calls usually drowned out by Snows in mixed flocks. Call a higher-pitched kenk kenk, often with a hesitating quality; sometimes repeated more quickly, kenk-kenk-kenk. Status: Common local breeder in n.-cen. Canada. Locally common to uncommon in the West; generally rare but increasing in the East. Migration mainly early Mar–early May, Oct–Dec. Within any region, averages earlier in fall and later in spring than Snow, but much overlap. Where rare, sometimes easiest to find early in fall migration or late in spring migration when Snow is less abundant. Winters to n. Mexico. Emperor Goose Anser canagicus L 66–71cm, Wt 2.5–3.6kg. A stately goose of the Bering Sea region, breeding in coastal tundra wetlands and wintering along rocky coasts. Rarely found se. of Kodiak Island, AK. Black throat and combination of white tail and dark undertail coverts distinctive. White head sometimes stained orange by iron. Sexes similar. Juv sooty overall; generally like ad by Dec, but dark markings on head and neck sometimes retained into summer. Bill and legs like ad by Apr. Sounds: High chattering calls, hoarse and usually rapidly doubled or tripled, kha-ha or khe-he-he. Also a ringing deep u-lugh when alarmed. Status: Locally fairly common. Migration mainly Mar–May, Sep–Nov. Returns to breeding grounds May–early Jun. Rare se. to CA, mainly near coast. Exceptional records from Interior West. Given strong preference for coastal habitats, overall rarity, and ease at which species is bred in captivity, sightings far inland and outside normal range best treated with caution. Also ne. Russia. 36

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Snow Goose

Large polymorphic goose with heavy bill white juv

Ross’s smaller, with shorter, thicker neck

intermediate ad

white juv white ad

white ad

dark juv

Snow × Ross’s hybrid

dark juv

dark ad

with Ross’s

with single Ross’s

Ross’s Goose

Smaller than Snow, with stubby bill, short, thick neck, and small head juv scapulars nearly black

white ad dark ad

juv much whiter than juv Snow whiter coverts and tertials than Snow

Emperor Goose

Stocky Bering Sea goose; rare s. of AK grayish overall juv

white tail

juv

often stained orange in summer

ads

1st-fall (Oct–Dec)

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Aythya DUCKS. Diving ducks that usually forage underwater, sometimes from surface. Often in large mixed flocks. Best identified by overall size and shape, particularly head and bill. Head shape varies with behavior: relaxed and sleeping birds show most “typical” shape. Beware of odd head shape on individuals molting head feathers.

Lesser Scaup Aythya aﬃnis L 38–48cm, Wt 640–910g. Widespread and common diving duck, generally most numerous s. of range of Greater Scaup and inland in migration and winter. Lesser and Greater are among the most difficult ducks to ID in N America, and care should be taken to note several characters (see Greater). ♂ nonbr duller than ♂ br, with brownish feathers on sides, sometimes with diffuse crescent at bill base. ♀ nonbr browner on back and head than ♀ br, with variable broad whitish patch on back of head (usually more extensive in Greater). Juv duller brown, plainer, paler, and darker-eyed than ad ♀. Acquires ad-like plumage gradually over winter; much individual variation. Most show mix of juv and ad-like feathers Nov–Mar. Ad-like 1st-yr usually retains some worn brownish juv feathers on belly and uppertail and undertail coverts. Sounds: ♂ generally quiet; when displaying, a soft whistled whew or faint wiiidooo. ♀ gives louder harsh, burry scaurp, often in series. Status: Common but declining. Spring migration protracted, late Feb–May, with wintering birds sometimes lingering into early May. Fall migration mainly late Sep–Dec. Molt migration Jun–Aug, when large numbers (up to 300,000 at single site) concentrate in taiga of cen. Canada. Winters to n. S America. Greater Scaup Aythya marila L 42–51cm, Wt 750–1360g. Hardy n. cousin of Lesser Scaup, generally wintering n. to limit of ice-free open water in bays, estuaries along both coasts, and Great Lakes. Breeds mainly on tundra pools and lakes in w. boreal forest. All plumages like respective plumages of Lesser and best identified by shape (suggests Redhead). Note more smoothly rounded or flatter head angled down to nape, without Lesser’s peak at rear crown. Bill is bigger and broader with deep base; larger nail often with black extending broadly onto bill tip. More extensive white on upperwing extends well onto primaries; on Lesser, white usually limited to secondaries or innermost primaries (♂s average more extensive white in both species, but strong light can obscure differences). In good light, head gloss of ♂ greenish in Greater, purplish in Lesser (this iridescence can change, as Mallard’s head can appear purplish). Distant birds and odd individuals, particularly in late spring and summer when head feathers are worn or being replaced, are best left unidentified. Aging, sexing as with Lesser. Sounds: Like Lesser but slightly lower-pitched. ♂’s display a bit more bubbling. Status: Common but declining. Migration late Feb–May, late Sep–early Jan. Also Eurasia. Ring-necked Duck Aythya collaris L 37–46cm, Wt 540–910g. Compact ring-billed diving duck breeding on small lakes, beaver ponds, and bogs that are often unable to support other waterfowl. In winter, favors inland lakes, ponds, and reservoirs, where it forages on aquatic vegetation. Agile in flight and able to rise quickly from water, allowing it to use more forested wetlands. Distinctive peak to head with dent behind crown, most obvious on ♂. Tricolored bill and white spur on sides of ♂ br distinctive. Namesake bronzy ring visible only when neck raised. ♂ nonbr similar to ♂ br, but bill dark gray, sides extensively brown. ♀ nonbr browner and less contrasting than ♀ br/w. Sounds: ♂ gives whistled scaup-like whew, sometimes longer; also a whistled teal-like pweep. ♀ gives variable burry grunts, often in long series. Status: Common and widespread. Migrates in early spring, Feb–early May, and late fall, late Sep–early Dec. Molt migration mainly Jun–Jul. Winters to Cen America, Caribbean. Tufted Duck Aythya fuligula L 40–47cm, Wt 550–1020g. Rare visitor from Eurasia, mainly to w. AK and e. NL but regular in Pacific Coast states and the NE. Very rare elsewhere. Usually found with large flocks of scaup or Ring-necked Ducks. ♂ has black back, gleaming white sides, and long shaggy tuft. 1st-w ♂ has short tuft and subtly off-white sides. ♀ has very dark head and back with paler brownish-gray sides and short spiky tuft. Both sexes have bold white wingstripe. ♀ Ring-necked has peaked crown, bold white ring on bill, gray wingstripe. Tufted regularly hybridizes in N America with both scaup and Ringnecked (see p. 73); beware individuals that appear pale-backed, short-tufted, or with darker sides. Sounds: Generally silent in N America. Status: Rare; mainly Oct–Apr, but records throughout year, mostly in AK. 50

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Lesser Scaup

Widespread scaup with peaked head

♀

1st-w ♂ (Nov–Apr)

♀

(Apr–Nov)

(Nov–May)

peak on rear crown

white usually limited to secondaries

♂

♀ darker, smaller,

violet gloss in good light

(Jun–Oct)

more compact than Redhead

♂

(Nov–Jul)

Greater Scaup

Large, round-headed scaup favoring coasts and Great Lakes in winter

♀

1st-w ♂ (Nov–Apr)

rounded head

(Nov–May)

(Apr–Nov)

usually greenish gloss white extends far onto primaries

♂ (Nov–Jul)

Greater

broad black nail

♂

(Jun–Oct)

often gleaming white

Lesser

head shape differences can be apparent on sleeping birds

Lesser has narrower head, bill, and nail

Compact diving duck with large conical head, narrow bill

♀

juv (Jul–Sep)

pale eyering and eyeline

(Apr–Nov)

Ring-necked Duck ♀

(Nov–May)

dark back

♂

1st-w ♂ (Oct–Feb)

(Nov–Jul)

♂ (Jun–Oct)

black back

gray contrasts with black wing coverts

grayish sides

Rare but widespread in N America, usually with other divers shorter tuft than ad ♂

1st-w ♂ (Dec–Mar)

Tufted Duck

rounded head, short tuft

♂

(Jun–Oct)

♀ sometimes

♀

has limited white

(Nov–May)

dark head and back long shaggy tuft

bold white stripe Aythya winter in large mixed species flocks

white spur

black back

sides darker in nonbr

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♂

(Nov–Jul)

EIDERS: Somateria and Polysticta. Four species of large, northern sea ducks. Breeding males are black and white with spectacularly patterned, colorful heads. Females and immatures are patterned in brown, cinnamon, and gray, variably barred black; identification relies on combination of head shape/pattern, bill shape. (Also see eiders in flight, p. 69). Males average larger, heavier; several species have modified scapular “sails.” Eat mainly mollusks, crustaceans. 1st-fall sexes similar with brown female-like plumage. Protracted molt from late fall through spring results in progressively adult-like plumage: note retained worn/bleached juvenile feathers on body, wings, and belly. Flightless for 4–6 weeks during synchronous wing molt in mid–late summer; males attain blackish-brown nonbreeding plumage during summer and gather in large groups (1000s) at molting sites. Large flocks winter in polynyas (openings and leads in sea ice). Many 1st-summer birds remain south.

Common Eider Somateria mollissima L 50–71cm, Wt 1.5–2.7kg. Large, spectacular eider with 4 distinct populations breeding across the Arctic and, unlike other eiders, also coastally s. through New England. Often nests in colonies and forms dense flocks in winter, when it is the default eider along rocky shorelines, inlets, jetties, often with scoters. All have wedge-shaped head, long bill. ♀s/juvs are bigger, browner than scoters, usually have extensively pale bills (vs. blackish in King and Spectacled Eiders), and have a low, straight gape line (cf. King). Ad ♀ usually has bold white tips to secondaries and greater coverts (cf. juvs), evenly barred plumage. Juv sexes similar through mid-fall; note faint pale tips to secondaries, greater coverts. 1st-yr ♂ acquires variable white breast and back Oct– Jan. 2nd-yr ♂ variable; some very similar to ad but with dark-edged tertials, others with more obvious signs of immaturity including brown crown, black-mottled upperwing coverts, variable black on head and breast, dull bill. Ad ♂ br plumage acquired in 3rd fall. Dusky nonbr plumage held in ♂s mainly Jul–Nov, with some retaining smudgy black on head, breast, scapulars into Dec–Jan. Late-molting ♂ nonbr can be confused with imm ♂ in Dec–Jan, but note all-white tertials, upperwing coverts, back. Tricky individuals best aged by wing pattern. Ad ♂s of the 4 ssp vary mainly in bill color and especially the shape and extent of frontal lobes (bare parts extending from bill to forehead), and shape of the area below the lobes where feathers meet the bill base; head patterns differ slightly. Ad ♀s differ in bill, lobe, head shape, and overall body coloration, but much variation and overlap in coloration. Sounds: A drawn-out, repeated pigeonlike cooing aaaaOOOoo during courtship; also soft chuckling and grunting. Status: Generally common. Migration mainly Mar–Apr, Oct–Nov. Rare inland, Gulf Coast. Also Eurasia. Common Eider (Pacific) Somateria mollissima v-nigrum Largest and most distinctive ssp: ad ♂ has bright orange bill, frontal lobes closely spaced, narrow, and pointed, with more extensive black border below; typically has extensive green below eye extending to nape, hard-to-see black V on chin (rare in other subspecies). ♀ best identified by pointed lobe shape, range. Status: Generally common. Rare vagrant away from AK. Also Asia.

Common Eider (Hudson Bay) Somateria mollissima sedentaria Ad ♂ round-headed, with yellow-orange bill, broad, rounded frontal lobes. Ad ♀ paler and grayer than Dresser’s, barred blackish, but much plumage overlap. Status: Common; resident in Hudson Bay, Canada. Common Eider (Northern) Somateria mollissima borealis Averages smaller; ad ♂ has orange bill, relatively short, tapered frontal lobes, white cheeks with green limited to nape. ♀ averages sandier than Dresser’s, but much overlap; intergrades regular. Status: Generally common. Some move s. to mix with Dresser’s, especially in Gulf of St. Lawrence region, but generally stays farther n. in winter. Also Europe. Common Eider (Dresser’s) Somateria mollissima dresseri Ad ♂ round-headed, with greenish-yellow bill (tending toward orange in Hudson Bay), broad, rounded frontal lobes. Ad ♀ averages richer rustier brown than Hudson Bay. Status: Common; the default eider on the Atlantic Coast in the Lower 48.

King Eider Somateria spectabilis L 47–63cm, Wt 1.6–2.4kg. Breeding ♂ looks airbrushed in pastel blue, green, and orange. Nests mainly on tundra ponds near the ocean. Mainly seen in winter, when a few move s., often with Common Eiders; most winter in polynyas. ♀ and juv from Common by rounder head, smaller, darker bill, “smiling” gape line, shorter neck, and suggestion of ♂ head pattern. ♀ averages rustier than most ♀ Commons, similar to Dresser’s ♀. Juv sexes similar through early Sep; ♂s usually have orange on bill by Oct. 1st-yr ♂ acquires variable white breast and back late in 1st fall–winter. 2nd-yr ♂ very similar to ad ♂, with more subdued head pattern. Ad ♂ br plumage acquired in 3rd fall. Sounds: ♂ gives a soft, quavering dove-like wooo-woooo; also soft chuckling, grunting. Status: Locally common Arctic breeder. Scarce in winter to coastal New England; rare elsewhere. Also Eurasia. 56

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On ♀/juv, note long sloping forehead/bill, extensively pale bill, low straight gape line

Pacific longer-billed; feathering more rounded, paler, ends short of nostril

Hudson Bay pointed, usually reaches nostril

Dresser’s Northern peaked forehead, pointed, just reaches/ long bill; tapered, falls short of nostril usually falls short of or even with nostril

Common Eider long orange bill, pointed lobes

Pacific ♂ (Nov–Jul)

usually pale patch Pacific 1st-fall/w ♀ very similar to ♂ nonbr; note brown wings, belly

Pacific ♂ (Jul–Nov)

Pacific ♀ (Nov–Jul)

Dresser’s 1st-s ♂

Pacific 1st-s ♂

Northern

♂

Northern ♀ (Nov–Jul)

Hudson Bay

♂

Dresser’s ♀ averages rustier, more rounded lobes than Northern

Dresser’s 2nd-w ♂ variable

Hudson Bay ♀ (Nov–Jul)

Dresser’s

♀

(Nov–Jul)

Dresser’s ♂ (Jul–Dec)

1st-w ♂ has brown juv wings, variable white breast, mottled back, black flanks

bolder white tips than 1st-w ad ♂ has all-white tertials

Dresser’s 1st-w ♂ (Oct–Jun)

Dresser’s

♂

(Nov–Jul)

On ♀s/juvs, note rounded head, short blackish bill, “smiling” gape line

King Eider

♀ (Nov–Jun)

juv/1st-fall ♀

1st-fall ♂ (Oct-Nov) 1st-w ♂ (Dec–Apr)

yellow-green broad, rounded lobes

♀

(Jul–Nov)

♂

(Jul–Nov)

♂

(Nov–Jun)

2nd-w ♂ (Nov–Jun)

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GUILLEMOTS: Cepphus. Medium-size alcids of nearshore waters; striking plumage, red feet and mouth lining in adults. Usually nest in rock crevices, cavities (even under piers, buildings) in isolated pairs or small colonies. Eat mainly fish, invertebrates. Note long neck, pot belly, broad, rounded wings in flight. Sexes alike. Molting birds appear mottled, as do many 1st-summer birds.

Black Guillemot Cepphus grylle L 30–32cm, Wt 320–485g. Flashy alcid of coastal New England and Atlantic Canada. Note white underwing coverts in all plumages and wholly white wing patch in most ads. Juv/1st-w has mottled white wing patch, duskier head/neck; paler orange feet/mouth lining (cf. molting murres, murrelets). 1st-s variable but with worn flight feathers, messier wing patch; lacks iridescence on body. Arctic breeders (mandtii; rare s. to New England) whiter in nonbr; juv has white-tipped secondaries. Flightless during late summer–early fall molt. Sounds: Vocal mainly when breeding. Song is a shrill, piping couplet series, relatively even-paced, often mixed with long plaintive whistles, sometimes wavering. Status: Common in the Atlantic; scarce in Bering Sea. Generally stays near breeding colonies, but n. populations pushed s. by sea ice in winter. In Atlantic, regular in winter s. to Cape Cod, MA, rare farther s.; exceptional to Great Lakes, se. AK in winter. Circumpolar. Pigeon Guillemot Cepphus columba L 30–35cm, Wt 450–550g. Pacific Coast counterpart to Black Guillemot. Best told from Black by dark grayish underwing, black wedge across white wing patch in ads. In areas of range overlap, Black usually much whiter in nonbr plumage. Juv/1st-w barred overall with messier wing patch, orange legs. 1st-s variable but with worn flight feathers, messier wing patch; lacks iridescence on body. Sounds: Vocal near nest year-round. Song is a shrill, piping twitter (faster than Black, often accelerating) often mixed with high, waxwing-like whistles (higher than Black). Status: Common but local. N. populations presumably move s. in winter; CA and OR breeders disperse n. post-breeding, mainly Aug–Oct, return Mar. Few winter CA, OR. Also ne. Asia. Brachyramphus MURRELETS. Small seabirds of cold nearshore Pacific waters. Pursuit-divers, feeding mainly on small fish. Fast-flying, buzzing low to the water, rocking side to side, often in pairs. Unlike other alcids, Brachyramphus species have cryptic breeding and more familiar black-and-white nonbreeding (winter) plumages. Not colonial; often nest inland: Long-billed (vagrant in North America) and Marbled Murrelets are the only tree-nesting alcids; Kittlitz’s Murrelet nests amid barren landscapes, scree. Molts into breeding plumage mainly March–April; molts into nonbreeding plumage mainly September–October. Flight feathers shed simultaneously (usually in September), when essentially flightless for ~8 weeks. Juveniles fledge August–September and look like duskier versions of nonbreeding adults through 1st winter. Sexes similar in all plumages. Generally shy of people and boats; often seen from shore; spring directly into flight from water (cf. auklets). Best identified by combination of range, habitat, and head, underwing, and tail patterns. Identification challenges particularly in Alaskan waters but also south along Pacific Coast, where Long-billed is a rare vagrant.

Marbled Murrelet Brachyramphus marmoratus L 24–25cm, Wt 258–357g. Elusive when breeding, this tree-nesting alcid of Pacific old-growth forest favors nearshore waters where pairs forage just beyond the kelp line. Intermediate between the other 2 Brachyramphus murrelets in size, bill length, and plumage. Note white scapulars in nonbr (cf. Synthliboramphus murrelets). Juvs arrive at sea mainly Jun–Aug, not accompanied by parent (cf. murre chicks). Sounds: Vocal in transit to/from nest sites; flight call a shrill, piping keeah or klee-oo. Status: Uncommon. Mostly winters in protected waters near breeding areas; rare s. of cen. CA; few vagrant records, none from interior (see Long-billed Murrelet, p. 581). Kittlitz’s Murrelet Brachyramphus brevirostris L 24–25cm, Wt 190–260g. Small, pale alcid tied to glacier waters of AK and Russia. Note prominent dark eyes against pale face, short fine bill, and relatively short tail. In flight, note white tail sides and white-tipped secondaries. Fresh juv duskier version of ad nonbr. Sounds: Usually quiet; not as vocal as Marbled Murrelet. Call a 2-part au-Wa. Status: Scarce and declining; winter range largely unknown, believed to include Gulf of Alaska, Bering Sea. Rare s. of AK. Also ne. Asia. 92

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1st-s

rounded wings

Arctic ssp distinctly paler

white wing patch

dumpy build, pot belly 1st-w

Black Guillemot

much white

1st-s

1st-w

br white underwing

br (Feb–Sep) nonbr (Sep–Feb)

juv (Jul–Sep)

Pigeon Guillemot

pale extreme split wing patch br

br 1st-s

1st-w

dusky underwing little white on wings; cf. murres, murrelets nonbr (Sep–Jan)

br (Jan–Sep)

juv (Jun–Sep)

Marbled Murrelet br juv (May–Aug) nonbr

white scapulars

white collar

black around eye

dark tail

nonbr/1st-w (Oct–Mar)

br (Apr–Sep)

Kittlitz’s Murrelet molting Marbled and Kittlitz’s nonbr

white edge

juv (Jul–Oct) white face nonbr/1st-w (Oct–Mar)

paler, more golden than Marbled

nearly complete collar white tail br (Apr–Sep) For general queries, contact info@press.princeton.edu.

Mottled Petrel Pterodroma inexpectata L 32–36cm, WS 84–92cm, Wt 205–440g. Distinctive, medium-size, fat-bodied petrel with high wing-loading. In moderate to strong wings often towers high and steeply, but like all gadflies (Pterodroma sp) can zigzag lower and into the wind when feeding; in calm conditions, flight usually low with quick deep wingbeats and long glides, but like other medium-size to large gadflies, at times flaps steadily 10–20m above the water, almost like a gull. Plumage distinctive, with pale silvery trailing edge to upperwing, bright white underparts with black underwing bar, and dark body contrasting with white wedge on undertail coverts (belly patch reduced when worn, mid–late summer). Beware confusion with oiled, white-bellied fulmars and shearwaters. Many spring–summer birds in wing molt. Status: Fairly common May–Oct from s. Bering Sea through Aleutians to Gulf of Alaska, mainly well offshore. Irregular uncommon migrant offshore s. to CA, mainly Oct–Dec, very rarely Mar–Apr. Breeds Dec–May in New Zealand. Cook’s Petrel Pterodroma cookii L 30.5–34.0cm, WS 76–82cm, Wt 115–250g. Small, snappy, fast-flying petrel with narrow wings, gleaming white underparts. Found mainly off CA, usually as singles but flocks in irruption years. Flight in calm usually low to water with deep, flexing wingbeats, long glides; in strong winds often towers steeply, slicing up and down like an errant boomerang. Note pale gray head and back (silvery in strong light; can appear darker-capped when worn), dark M pattern on fresh upperparts, very narrow black underwing margins. Many spring–summer birds in wing molt, when flight less dynamic. No similar species occur regularly, but cf. Buller’s Shearwater, Hawaiian Petrel. Status: Uncommon to fairly common well off CA Apr–Sep (rarely to Dec); very rare Jun–Dec n. to BC and s. AK; usually absent from range of day-trip boats, but some years present in small numbers mainly Jun–Aug. Breeds Nov–Mar in New Zealand. Hawaiian Petrel Pterodroma sandwichensis L 37.5–40.0cm, WS 94–104cm, Wt 355–540g. Distinctive, medium-size to large, long-tailed gadfly increasingly seen off W Coast. Found singly, usually not with other species, but like all gadflies is attracted to chum slicks. Flight in moderate to strong winds dynamic, wheeling fast and high; in calm, flies low, weaving buoyantly with easy clipped wingbeats, glides on flexed wings. Plumage distinctive, with dark brown upperparts (fresh plumage frosty gray, unrecorded off W Coast), white forehead, thick black underwing margins, clean white undertail coverts. No molting birds yet found off W Coast. Status: Rare but increasing, Apr–Sep, mainly CA but also n. to BC. Breeds Apr–Oct in HI. Murphy’s Petrel Pterodroma ultima L 34–37cm, WS 89–97cm, Wt 335–425g. Only dark-bodied gadfly petrel regular off W Coast, mainly in spring. Flight typical of stocky, medium-size gadflies, wheeling steeply and high in strong winds, gliding buoyantly and low in calm, with clipped wingbeats. Found singly or in loose groups, usually well offshore and not with other species. Plumage distinctive, with strong silvery-gray sheen on upperparts (especially when fresh, in spring) setting off blackish M pattern; silvery wing flashes mainly on underside of primary bases. Head often appears as dark hood with variable whitish patch at bill base, which is stouter than slender bill of shearwaters. Cf. Sooty Shearwater. Status: Irregular migrant from CA n. to Gulf of Alaska, usually well offshore beyond the reach of day-trip boats; in some years found in good numbers but typically scarce. Found off W Coast mainly Feb–Jun, especially mid-Apr–early May; very rare Jul–Dec. Breeds Jun–Dec in subtropical s.-cen. Pacific.

108

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Mottled Petrel

Medium-size, fat-bodied; colder waters

spring/summer wing molt

dark cowl, dusky sides; cf. Cook’s

thick black variable gray belly contrasting with white vent

Cook’s Petrel

Small, snappy; bright white below

head and back pale gray

clean white below spring/summer wing molt

Medium-size to large, lightly built, long-tailed

Clean white; cf. Pink-footed Shearwater

fresh (browner above when worn)

Hawaiian Petrel

long tail

bold black

white forehead stands out, even at a distance

black cap with white forehead blaze

Murphy’s Petrel

Medium-size, stocky, dark-bodied

silvery-white underwing flashes vary with light, angle

uniform gray crown and back, white brow

silvery-gray sheen above with blacker M pattern

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with Sooty Shearwater

ALBATROSSES: Diomedeidae. Huge seabirds with long narrow wings, heavy bodies, long bills. Ages differ; sexes similar. Rarely seen from shore. Often scavenge at fishing boats, where 10s–100s gather with fulmars, gulls. Mostly silent at sea, but high whistles, whinnies, and bill rattles given in interactions. Flight labored in light winds, low to the water, but birds wheel high and easily in strong winds. Note overall color patterns, bill size and color. 3 species regular, 8 vagrant.

Black-footed Albatross Phoebastria nigripes L 71–82cm, WS 200–220cm, Wt 2.6–4.3kg. Fairly stocky-bodied, overall dark brown albatross; common off W Coast in summer, when many birds in wing molt. All ages dark overall with whitish band around bill base, dusky to dull pinkish bill, blackish feet; bleached whitish head can occur on imms and ads (extreme birds might be mistaken for very rare Laysan × Black-footed hybrid, which is variably intermediate in appearance, mainly occurs in AK). Rarely has pinkish bill, but duller and smaller than bill of Short-tailed Albatross. Juv has uniform remiges, pointed P10. Older ages develop white on tail coverts, starting at 4–5 years on some ♂s, later on ♀s. Undertail coverts mostly white before white appears on uppertail coverts. Status: Fairly common to common. Occurs year-round, mainly Apr–Oct off W Coast, May–Sep off AK. Can be seen from shore (e.g., Point Pinos, CA) mainly Apr–Jul. Breeds Nov–Jul in HI and Japan. Laysan Albatross Phoebastria immutabilis L 71–79cm, WS 195–215cm, Wt 2.4–4.1kg. Fairly lightly built Pacific albatross, uncommon off W Coast, common off Aleutians in summer. On the water recalls giant Western Gull but more hunchbacked, with long pinkish bill. Juv lacks well-defined gray cheeks, often has black eye patch, little/no orange on bill. Gray cheeks attained in 1st or 2nd year, after which looks like ad. Hybrids with Black-footed Albatross very rare. Status: Uncommon to fairly common. Occurs year-round, mainly Aug– May off W Coast, May–Oct off AK. Increasing since 1990s off CA with juvs in Aug–Oct from growing Mexican population. Exceptional May–Jun inland in the SW. Breeds Nov–Jul in HI; also nw. Mexico since 1980s. Short-tailed Albatross Phoebastria albatrus L 80–90cm, WS 220–240cm, Wt 5.1–7.5kg. Spectacular large-bodied albatross, very rare off W Coast, regular in summer off Aleutians. All ages have diagnostic huge pink bill with pale blue tip. White plumage develops with age, more quickly on ♂s. W Coast records are stage 1 imms (cf. Black-footed Albatross). Ad (stage 7) striking and unmistakable with golden hindneck, white back and inner half of upperwings. Juv blackish brown overall. White appears first on face, foreneck, and breast; underparts mostly white before white appears on rump and uppertail coverts, then on mantle and scapulars, lastly on hindneck and upperwings. Stage 1: dark overall; legs and feet dark with variable pinkish tones. Stage 2: face, foreneck, and underparts become white; upperparts brown or with some white mottling on distal tail coverts. Stage 3: lower back to uppertail coverts develop extensive white. Stage 4: back becomes mostly white, still with brown mottling, and dark cowl contrasts with white mantle; scapulars start to show white. Stage 5: back and scapulars clean white or with scattered dark marks; some have golden crown and nape, narrow dark hindcollar. Stage 6: cowl golden with reduced or no dark hindcollar; white to silvery develops on humeral coverts. Stage 7: no dark on hindneck; white scapulars, humeral coverts, and elbow patch form big white wing panel. Status: Very rare year-round off W Coast mainly Aug–May; uncommon to locally common off Aleutians and in s. Bering Sea, where concentrations of 100+ birds can occur around fishing boats, mainly May–Oct. Breeds Oct–Jun in s. Japan.

with Northern Fulmars

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Black-footed Albatross bill rarely pinkish

strongly bleached

mostly or wholly white

imms oldest birds solid white

white appears first on undertail coverts dark for at least 4–5 years

subad molting

Laysan Albatross

albatrosses with Western Gull

black underwing markings highly variable

1st-yr often “goggle-eyed” on white face lacks well-defined gray cheeks

1st-yr

finely serrated border

ads

uniform remiges

with Black-footed

well-defined gray cheeks

smoother border than 1st-yr

Short-tailed Albatross

All ages have huge pink bill whitens first on underparts

stage 2

ad stage 7

stage 5

stage 6

stage 4

stage 1

dark overall for 2–3 years stage 3

ad stage 7

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IDENTIFYING IMMATURE JAEGERS. For juvs, 1st-yrs, and some 2nd-yrs, the best ID features are overall size and structure, number of white primary shafts on upperwing, length and shape of central rectrices, pattern of white on underside of primaries, pattern of pale barring on tail coverts and axillars, bill size and shape. Juveniles (Aug–Dec). Long-tailed: Typically cold gray-brown, lacking rusty tones of Parasitic. Axillars and tail coverts have regular bold whitish to buff barring; tail projection relatively long, bluntly pointed. Often has dark breast contrasting with paler or white upper belly patch. White flash under primaries often invaded by dusky wedge on inner web of P10, unlike juvs of other jaegers (but 1st-s birds of all 3 species can show this feature). Appears in Lower 48 late Aug–Sep. Parasitic: Typically warm, medium to dark brown with variable rusty tones overall, paler below (lightest on lower belly/vent) but not white, with rusty-streaked nape. Axillars and tail coverts have irregular buff to rusty barring; tail projection short but pointed. Appears in Lower 48 late Aug–Sep. Pomarine: Typically cold dark brown overall, paler below, with darker head; nape mottled paler. Axillars and tail coverts have regular pale barring; tail projection short, thick, and blunt. Appears very late in Lower 48, Oct–Nov.

Juvenile jaegers Long-tailed

Parasitic

Pomarine

usually warm-toned

usually cold-toned

stocky build faintly mottled

small head

bold, even barring

wavy, often dull

bold, even slender bill

small bill

pointed

thin, rounded

2–3 white shafts

dusky wedge

132

blunt

crescent of white shafts

bold white flash

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big head and bill

4–8 white shafts

whitish base

Juvenile jaegers

Long-tailed small bill

more rounded than Parasitic pale tips small or lacking

Pomarine faintly mottled

no pale tips

stocky build; usually cold-toned

Parasitic

big head and bill

rusty streaking

bold, even pale tips usually distinct

small head, slender bill

bold, even

wavy, often dull

juvs found inland can be disconcertingly challenging, despite often being tame and approachable (1st-s exceptional inland)

1st-summers (May–Oct). Occur off W Coast mainly Jul–Oct, off E Coast late May–Sep. Resemble juvs but lack pale tips to upperwing coverts and have tail projections more like ad; often retain 1–3 juv outer primaries in spring. Long-tailed: Typically has wire-like tail projections (rarely broader, like Parasitic) or a central notch where R1 is missing. Fairly common off W Coast; rare to uncommon off E Coast. Parasitic: Has pointed tail projections (rarely fine, like Long-tailed). Uncommon to fairly common, both coasts. Pomarine: Has thick blunt tail projections; can be hard to distinguish 1st-s from delayed 2nd-s. Fairly common off both coasts.

1st-summer jaegers Long-tailed

Parasitic

Pomarine

broad wings molt to 2nd-w Sep–Nov usually wire-like

sharply pointed

often more evenly barred than Long-tailed

1–2 white shafts

R1 often shed in fall

sharply pointed

evenly barred

can have deep cap like Pomarine, but note whitish forehead

wavy barring bleached white shafts of old juv feathers suggest Long-tailed

faded juv outer primaries and secondaries

little contrast

big bill

molting 1st-yr Long-tailed in spring

short, blunt

evenly barred

1st-yr Parasitic in spring mostly white underwing shown by some 1st-yr Pomarines and Parasitics

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1st-s Pomarine

Iceland Gull complex. 3 taxa of medium-size to large “white-winged” 4-year gulls breeding from Arctic Canada to Greenland; Thayer’s Gull and Kumlien’s Gull are widespread in winter in n. N America, while s. and e. Greenland breeders (glaucoides) winter primarily in n. Europe. Wingtip pattern darkest in Thayer’s Gull, intermediate in Kumlien’s Gull, and palest in Greenland breeders. Taxonomy vexed and evolving, and all 3 have been variously treated as species and subspecies over the years; here treated as well-defined subspecies, though more study is clearly needed.

Iceland Gull (Kumlien’s) Larus glaucoides kumlieni L 48–62cm, WS 122–140cm, Wt 530–970g. Winters in the NE mostly at sea and along coasts at harbors, dumps, beaches. Breeds locally on cliffs and rocky islands in Canadian Arctic. Wingtip pattern highly variable: most ads have medium to dark gray markings on wingtips, but wingtip ranges from white overall to dark slaty (extent of possible intergradation with Thayer’s and the nominate ssp remains unknown). Ad typically has pale eyes, orbital ring purplish pink to reddish. Most Kumlien’s readily identified, but darkest-winged birds not safely told from paler-winged Thayer’s (and some may be intergrades). At the other extreme, birds breeding in s. and e. Greenland (glaucoides) perhaps not safely distinguishable from whitest-winged examples of presumed Kumlien’s, but ad Greenland upperparts slightly paler gray, similar to Canadian Glaucous Gull. 1st- and 2nd-yr Kumlien’s typically have medium brown to whitish wingtips (dark brown on Thayer’s); juv tertials often more finely and extensively patterned than Thayer’s. Also cf. hybrid American Herring × Glaucous Gull and, in the West, Glaucous-winged Gull and other hybrids (p. 156), all of which are larger, bulkier, and bigger-billed than Kumlien’s. Aging criteria much as for other large gulls. Sounds: Poorly known. Typical large gull calls, slightly higher and harsher than American Herring. Status: Fairly common to common in winter mainly Nov–early Apr in Atlantic Canada; smaller numbers s. to New England and e. Great Lakes; scarce to w. Great Lakes and Mid-Atlantic coast mainly Dec–Mar. Very rare or exceptional elsewhere in N America (mainly winter) s. to FL and Gulf Coast and in the West. Nominate Iceland Gull breeds s. and e. Greenland; winters Iceland to nw. Europe, very rarely in the NE, exceptional elsewhere in N America. Kumliens’ Gull

poorly marked, rarely all white

ad wingtip variation

paler than Thayer’s

Thayer’s Gull

Kumlien’s-like

some have reduced white

Thayer’s with American Herring × Glaucous-winged hybrid

Iceland Gull (Thayer’s) Larus glaucoides thayeri L 50.0–63.5cm, 122–140cm, Wt 710–1150g. Darkest-winged gull in the Iceland complex, wintering mainly in the West. Wingtips slaty blackish in typical ad to dark brown in juv. Ad has deep pink orbital ring; eyes typically dusky (pale on ~20% of birds); all ages have pink legs. Winters in coastal bays, harbors, dumps, beaches, locally inland along rivers and at lakes. Breeds locally on coastal cliffs and rocky islands in Canadian High Arctic. Plumage variation compounded by possible intergradation with Kumlien’s ssp. Most frequent ID concern is American Herring Gull, but also cf. dark-winged Kumlien’s, 1st-yr Glaucous-winged Gull, and hybrids (p. 156). Hybrids generally larger, bulkier, and bigger-billed than Thayer’s, but wingtip patterns can be seemingly identical. Thayer’s averages smaller and shorter-legged than American Herring, with smaller bill. Ad best told from American Herring by combination of structure and wingtip pattern: above, white-tipped pale “tongues” (see p. 139) cut into blackish wingtip on spread wing, vs. more solidly black wingtip of American Herring; below, wingtip silvery overall with narrow blackish trailing edge. Also, eyes typically dark, legs often richer pink, white trailing edge to wings broader, dusky neck markings more smudged. Juv/1st-yr from American Herring by combination of structure and upperwing pattern: above, primaries blackish brown to medium dark brown with more strongly contrasting pale inner webs creating venetian-blind pattern and blending with paler inner primaries (American Herring has stronger contrast between more solidly dark outer primaries and paler inner primary panel). Upperparts of Thayer’s often frostier, more checkered overall, with distinct, fine whitish tips to closed primaries. Aging criteria much as for other large gulls. Sounds: Poorly known. Typical large gull calls, slightly higher and harsher than American Herring Gull. Status: Fairly common, wintering mainly from coastal se. AK to cen. CA, locally inland in the West, with small numbers on Great Lakes; uncommon to rare in s. CA mainly Dec–Mar; rare or very rare elsewhere in N America. Arrivals on W Coast mainly late Oct–Nov, departing Feb–early Apr.

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Iceland Gull (Kumlien’s)

Highly variable, medium–large winter gull of the NE; relatively small bill, short legs imm pattern

3rd-w

less contrasting than Thayer’s

ad pattern

1st-w lacks contrasting dark secondary bar

nonbr 2nd-w highly variable 2nd-w (Sep–Apr)

1st-yr highly variable medium brown

bare parts brighter in summer br

often checkered and “frosty”

3rd-w (Sep–Apr)

1st-w (Sep–Apr) can have white wingtips

nonbr (Sep–Apr)

Variable, medium–large winter gull of the West; relatively small bill, short legs worn 1st-yr (Mar–May)

2-toned outer primaries

darker than Kumlien’s more strongly 2-toned than American Herring

Iceland Gull (Thayer’s)

3rd-w

nonbr

not as dark as American Herring

2nd-w 1st-w dark brown with whitish edges

bare parts brighter in summer

plumage variable

blackish 2nd-w (Sep–Apr)

1st-w (Sep–Apr)

dark eyes

3rd-w (Sep–Apr)

dark brown; cf. Kumlien’s

nonbr (Sep–Apr)

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richer pink legs than American Herring

DOWITCHERS: Limnodromus. Two very similar species characterized by long bills used to probe “sewingmachine” style. Feeding flocks cluster in shallow to belly-deep water. In flight, both dowitchers show a prominent white stripe on rump and lower back. Identification complex, compounded by 3 subspecies of Short-billed. Best identified by voice and plumage details. Habitat preferences distinct in winter, less so during migration. Bill lengths overlap, but extremes distinctive (females longer-billed than males in both species); other differences in structure useful only with experience. Cf. Stilt Sandpiper, Dunlin.

Long-billed Dowitcher Limnodromus scolopaceus L 25.5–29.0cm, Wt 90–135g. The “rufous-bellied dowitcher” breeds in wet coastal tundra and winters mostly at freshwater sites, also coastal lagoons and tidal pools. Note diagnostic calls (see below). Structural differences from Short-billed Dowitcher subtle: Longbilled averages larger with slimmer bill, more laterally compressed body; rounder body while feeding; more upright stance while sleeping; shallower forehead/longer “snout”; some ♀s have distinctively long bill and legs. All plumages generally darker than Short-billed, with relatively broad dark tail bands and contrasting whitish lesser coverts on underwing. In Apr–May, look for white-tipped scapulars, white-edged black bars on breast sides. After white tips wear off in Jun–Aug, look for mostly unmarked rufous belly contrasting with dark upperparts, short black bars on breast sides. Ad nonbr usually darker than Short-billed, with airbrushed smoothness to breast and flank markings, few/no spots invading white belly. Juv grayer, less patterned than juv Short-billed. On molting ads in Aug–Sep, look for combination of rufous belly and smudgy gray flank bars. Ads molt primaries (mostly Aug–Sep) at stopover sites, often away from wintering areas (cf. Short-billed). Sounds: Flight call a sharp whistled peep, given singly or in a quick series; distinctly higher than Short-billed and frequently given by feeding birds. Song a gurgled dddd-dee-drr, similar to Short-billed but slightly higher and buzzier with last element lower. Status: Breeds e. Siberia to nw. Canada. Common migrant through much of the West and South, including inland; more local in the NE, mainly in fall. Fall migration (especially juvs) later than Short-billed. Migrates mainly mid-Mar–May, mid-Jul–Sep (ads), Sep–early Nov (juvs). Winters to Cen America. Rarely oversummers in wintering areas. Long-billed with Central Short-billed (early Apr)

1st-w Short-billed and Long-billed

Short-billed Dowitcher Limnodromus griseus L 24–28cm, Wt 85–130g. The “orange-breasted dowitcher” breeds in subarctic tundra–boreal forest transition and winters strictly along the coast, particularly at tidal flats, saltmarsh pools. Note diagnostic calls (see below). Compared to Long-billed Dowitcher, Shortbilled’s dark tail barring ranges from much narrower to very similar; lesser coverts on underwing usually more patterned; bill averages thicker, blunter-tipped, often more kinked downward, and often with brighter yellow base; some ♂s distinctively short-billed. 3 ssp differ mainly in br plumage; all are variable, and some intergrades occur. Ad br Atlantic (griseus) and Pacific (caurinus) birds show distinctive combination of white belly and variably orange-washed breast. Central birds (hendersoni) brighter and more similar to Long-billed; look for paler orange underparts fading to whiter belly, broader orange markings on upperparts, more evenly distributed dark markings along flanks including spots (not bars) at breast sides. Ad nonbr from Long-billed by weaker breast to belly contrast, speckled look to breast, usually dark flecks invading white belly, and usually thinner, more chevron-shaped flank markings; Central birds palest, Pacific birds darkest (as dark as Long-billed). Juv usually much more colorful and boldly patterned than juv Long-billed; Central juvs average brightest. Ad molts primaries (mostly Aug–Sep) along coast, at or near wintering grounds (cf. Long-billed). 1st-s birds often retain extensive nonbr plumage, molt primaries Jun–Aug at coastal stopover sites. Sounds: Flight call a low, quick 2–4-note kyu-tu-tu, given in flight, rarely while standing. Song is a gurgled d’d’d’d’dee-droy, often preceded by a few whistled teedle-ee phrases recalling Lesser Yellowlegs. Status: Breeds s. AK (Pacific), w. and c. Canada (Central), and e. Canada (Atlantic). Migrants common along coasts, more local inland; rarer through Interior West. Pacific migrates mainly along Pacific Coast, sparingly inland; Central from Great Plains eastward, sparingly farther w. and to New England; Atlantic through the NE, sparingly to e. Gulf Coast. Migration mainly mid-Apr–early Jun, late Jun–early Aug (ads), Aug–mid-Sep (juvs). Winters to n. S America. A few oversummer in wintering areas. 192

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Short-billed Dowitcher

Long-billed Dowitcher Mostly freshwater sites in winter; calls diagnostic

both have white stripe

longer than Short-billed bold white tips wear away by Jun

evenly patterned

contrasting whitish

thick bars

Rarely far from salt water in winter; calls diagnostic

thin bars

nonbr

♂ fresh br (Apr–May)

nonbr

1 br Long-billed with Short-billeds; note belly color, underwing pattern

broad orange markings thin bars rufous brightest on belly

Central ♂ br (Apr–May)

dark with narrow bars, no pale edges

orange brightest on breast Pacific ♀ br (Apr–May)

colorful with distinct pale edging mainly bars at breast sides

mainly spots at breast sides

clean rufous belly many ♀s have distinctively long, slim bills

similar to Central; averages darker overall, paler belly

a few spots into belly

Central ♀ worn br (Jun–Jul)

♀ worn br (Jun–Jul)

Atlantic ♂ br (Apr–May)

some ♂s have distinctively short, heavy, kinked bill white belly

Aug flock with both dowitchers and Lesser Yellowlegs

plain pattern

usually prominent internal markings

usually much brighter than juv Long-billed blackish streaks

plain gray juv (Aug–Nov)

duller juv (Jul–Nov) smudgy gray

smooth gray nonbr (Sep–Apr)

black spots

brighter juv (Jul–Nov)

often white edges speckled

thick, smudgy bars

usually clean white

darker nonbr (Aug–Apr)

belly invaded by dark flecks

thin chevrons paler nonbr (Aug–Apr)

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Dunlin Calidris alpina L 19.5–21.5cm, Wt 48–70g. A bird of expansive tidal flats, this stocky sandpiper with longish drooped bill is widespread and locally abundant along the coast in winter. Dark hood distinctive in nonbr. Gaudy br plumage attained late Apr–May before return to tundra nesting grounds. Moves constantly as it picks and probes in mud or shallow water. In nonbr, cf. smaller, paler, whiter-breasted Western Sandpiper; Stilt Sandpiper slimmer, has longer yellowish legs, white rump. Sexes similar; ♂ shorter-billed, ♂ br averages whiter-faced. A few 1st-s birds remain on wintering grounds all summer; attain variable, often dull br plumage; retain worn juv outer primaries into Aug–Sep. Taxonomy complex. 2 widespread ssp in N America: pacifica breeds w. AK, winters Pacific Coast; hudsonia breeds cen. Canada, winters Atlantic and Gulf Coasts. Birds breeding in Beaufort Sea region (arcticola) winter primarily se. Asia, as do birds from ne. Asia (sakhalina Group), which migrate through w. AK; both look similar to pacifica but average smaller, shorter billed. Greenland breeders (arctica and schinzii), vagrants to E Coast (mainly Aug), molt on wintering grounds (AK, Canada breeders molt on breeding grounds). Sounds: Flight call a relatively low, raspy, level-pitched jeeep. Song a gurgling chatter, descending and slowing (3–4 secs); introduced by a series of rising buzzy notes (1/sec). Status: Common. Winters abundantly along coasts; more local inland during winter and migration. Ads molt primaries Jun–Sep in AK/Hudson Bay, arrive Lower 48 mid–late Sep. Migration mainly Apr–early Jun, Sep–Nov. Winters to Mexico. Also Old World.

Purple Sandpiper Calidris maritima L 20–22cm, Wt 56–74g. Small flocks of this hardy dark shorebird occur on wave-washed rocky shores and jetties in winter, often with Ruddy Turnstone. Hops and flutters from one rock to the next; seldom on beaches. Nests on barren tundra. Distinctive in range, but cf. paler, black-legged Dunlin. Nonbr from allopatric Rock Sandpiper by suite of average characters: smoother gray upper breast (more speckled in Rock), thinner belly streaks (Rock has darker, rounder belly spots), supraloral spot separated from more complete eyering (fuller supraloral stripe, weaker eyering on Rock), more orange-toned legs and bill base, thinner wingstripe; much overlap in bill length, but some ♂ Rocks distinctively short-billed. Namesake purple sheen on nonbr scapulars, visible in ideal light, often present on Rock. Sounds: Flight calls include a muﬄed chrk and higher, scratchy keef. Giggling toy-toy-toy threat call similar to Semipalmated Sandpiper. Song includes rhythmically repeated, burry duree notes (~1+/sec) and quicker boo-dee phrases. Status: Locally fairly common in the NE; scarce migrant through Great Lakes, very rare on Gulf Coast, exceptional in the West. Molts primaries in the Arctic; seldom arrives in the Lower 48 before mid-Oct, but a few nonbreeders oversummer in wintering areas. Migrates mainly Apr–May, mid-Oct–Nov. Also n. Europe. Rock Sandpiper Calidris ptilocnemis L 18–24cm, Wt 63–119g. A coldweather bird wintering on n. Pacific Coast, found mainly on wave-washed rocks but also gravel beaches, tidal flats. Nests on Arctic tundra, where ♂s lift 1 wing, flashing white underwing, at end of their display. Distinctive, but cf. Dunlin, Surfbird, allopatric Purple Sandpiper. 3 ssp in N America: Pribilof (ptilocnemis), largest, palest, longest-billed, breeds Bering Sea islands, winters to s. AK, rarely WA; Aleutian (couesi), darkest, is largely resident on Aleutian chain, but some movement occurs, extent not well known; Bering Strait (tschuktschorum), intermediate, breeds w. AK mainland, winters to n. CA. Sounds: Calls similar to Purple. Songs include rhythmically repeated, nutcracker-like koraaa (~1/sec) and quicker, buzzier di-jrr phrases (variable). Status: Locally common in AK, where flocks of 1000+ can gather at favored staging or wintering sites (late Jul–Mar); progressively less common to the s. in winter: uncommon and local from WA to n. CA, rare to cen. CA. Molts primaries Jul–Oct in AK; seldom arrives in Lower 48 before mid-Oct. Migrates mainly Apr–May, Oct–Nov. Also ne. Asia.

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rare on Atlantic Coast; small and short-billed

nonbr with Western Sandpiper

arctica/schinzii ♂ br

♂s average whiter-faced

1st-s birds vary from full nonbr to partial br

nonbr

Dunlin

pacifica ♂ br (Apr–Aug)

hudsonia 1st-s scapulars, belly streaks usually replaced by late Sep

clean white

flanks cleaner white on pacifica

juv (Jul–Sep)

dark hood hudsonia nonbr (Sep–Mar)

Rocky shores on Atlantic Coast

hudsonia ♂ br (late Apr–Aug)

streaked

Purple Sandpiper

purple sheen visible in ideal light

pale eyering and loral spot

nonbr with Dunlin

replaces scapulars by Oct, before arriving in Lower 48

crisp white fringes

juv (Jul–Sep)

nonbr (Sep–Apr)

orangish

br (Apr–Aug)

1st-w (Sep–Apr)

Rock Sandpiper

Highly variable plumage; all with messy underparts, dark cheek patch Pribilof nonbr

Bering Strait/ Aleutian nonbr

Pribilof nonbr larger, paler, lighter streaking

pale rufous

dusky limited black Aleutian br (Apr–Aug)

heavy streaks

paler, more finely streaked than Bering Strait/ Aleutian

extensive white bright rufous edging

Pribilof juv (Jul–Oct) buffy wash Bering Strait/ Aleutian juv (Jul–Oct)

pale rufous usually distinct supraloral stripe

Bering Strait/ Aleutian nonbr (Sep–Apr)

strongly contrasting spots

yellowish heavy streaks

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faint streaks deep reddish

washed orange Pribilof br (Apr–Aug)

Bering Strait br (Apr–Aug)

PRAIRIE GROUSE and SAGE-GROUSE. Uncommon and declining birds of extensive open areas. Generally difficult to detect except in breeding season, when they gather on leks to display.

populations in decline.

Sharp-tailed Grouse Tympanuchus phasianellus L 40–48cm, Wt 600–1030g. Favors transitional habitats between prairie and woodland, less often farmland. Often perches in trees and feeds on buds, particularly when snow covers ground. Differs from prairie-chickens by scalloped underparts, white belly, and paleedged pointed tail (most noticeable in flight). Complex regional variation: palest in w. prairies, darker in n. Sounds: ♂ gives variety of cackles, gobbles, coos, and popping sounds on lek; also a fluttering sound made by rapid foot stomping. When flushed, both sexes give a kuh kuh kuh kuh, much softer than a pheasant (not guttural). Also various clucking notes. Status: Fairly common, but s. Greater Prairie-Chicken Tympanuchus cupido L 41–47cm, Wt 700–1200g. Large grouse, generally confined to native grassland and surrounding agricultural areas. Cf. Lesser Prairie-Chicken, Sharp-tailed Grouse. Hybridizes with Sharp-tailed; infrequently with Lesser in narrow zone of overlap in w.-cen. KS. Attwater’s ssp (attwateri) of se. TX critically endangered; upperparts average tawnier, and lower legs lack feathering. Sounds: At breeding lek, ♂’s booming is a low far-carrying hoot that sounds like air being blown over the top of a bottle. Also chicken-like clucks. Status: Once abundant, now largely uncommon and heavily managed. Heath Hen ssp (cupido) of coastal MA to VA extinct. Lesser Prairie-Chicken Tympanuchus pallidicinctus L 38–41cm, Wt 620–900g. Scarce grouse found locally on sand sage and shortgrass prairie of s. Great Plains. Very similar to Greater; best separated by range. Note Lesser’s dull red air sacs; paler, more finely barred underparts; and voice. ♂ has longer pinnae than ♀, dark central tail feathers (barred in ♀). Sounds: ♂’s booming is highpitched and yodeling; quite different from low, mellow, and drawn-out boom of Greater. Other courtship calls wild and frenzied, even more intense than Greater. Status: Uncommon; declining. Greater Sage-Grouse Centrocercus urophasianus L 56–72cm, Wt 1.5–2.9kg. Very large, long-tailed, black-bellied grouse; favors large expanses of sage and nearby grassland. Sounds: ♂ rapidly inflates and deflates air sacs, producing 2 low plopping sounds; these are accompanied by wing swishes and tail rattles as he moves. When flushed, both sexes give rapid clucking kek-kek-kek. Status: Uncommon and declining, precipitously in many places. Small-scale movements tied to food availability.

Gunnison Sage-Grouse Centrocercus minimus L 32–51cm, Wt 1.1–2.1kg. Smaller s. counterpart of Greater; no range overlap. Gunnison has conspicuous pale tail bands, which give tail blond appearance at a distance. Sounds: Similar to Greater. During each display, Gunnison typically produces 9 plopping sounds with air sacs, while filoplumes (longer thick feathers on back of head) are thrown over top of head and flop back down. Greater makes only 2 plopping sounds, and short head feathers remain in place. Status: Endangered. Restricted to Gunnison Basin and nearby areas of CO and se. UT.

242

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Sharp-tailed Grouse

Great Plains cf. ♀ Ring-necked Pheasant

pointed with white edges

♂

(sexes similar)

northern

scalloped breast pale belly

♂ has purple air sacs

Sharp-tailed Grouse × Greater Prairie-Chicken hybrid

Both prairie-chickens barred below

Greater Prairie-Chicken

♂ Attwater’s

♀ ♂

orange air sacs

Lesser Prairie-Chicken

short, rounded tail in both prairie-chickens

♀

♂

tail patterns similar in Greater

paler and grayer than Greater

deep red air sacs

long tail

♂

Greater Sage-Grouse

♀

♀ black belly

♂

displaying ♂

Gunnison Sage-Grouse

Restricted to w. CO and se. UT longer filoplumes than Greater

♀

♂

displaying ♂

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EAGLES: Adults. See immature eagles on p. 256.

Bald Eagle Haliaeetus leucocephalus L 70–90cm, WS 180–243cm, Wt 2.5–6.6kg. Large distinctive eagle found throughout N America; associated with water but often found far from it. Builds huge stick nests, usually in trees. Roosts communally in winter near abundant food sources where dozens to 100s can gather. Eats mainly fish, carrion; often steals from Osprey. Direct flight steadier than vultures with deep, even wingbeats typically ending on a downstroke; soars widely on flattish plank-like wings; head and tail similarly long. Golden Eagle has smaller head and bill, soars with wings in dihedral, and has dark underwing coverts and axillars in all plumages. Cf. Osprey. Takes 4–5 years to attain ad appearance. Sounds: Gives a descending series of weak whistles, not the classic Hollywood raptor scream (that’s Red-tailed Hawk). Status: Fairly common and increasing in most of range. N. populations migratory, moving mainly Feb–May, Aug–Dec; s. birds resident, but northward post-breeding dispersal extensive. Also n. Mexico. Osprey with 3rd-yr Bald Eagle and ad Great Black-backed Gull

glides on flat to slightly bowed wings

glides with modified dihedral

M-shaped wings

Golden Eagle Aquila chrysaetos L 70–90cm, WS 185–225cm, Wt 3.0–6.4kg. Large, dark, powerful hunter of w. mountains and open country, preying primarily on small to medium-size mammals and birds. Breeds mostly on mountain cliffs, open-country buttes. Winters in more varied habitat throughout the West, more sparsely in e. mountains, forest, and saltmarsh. Unlike Bald Eagle, generally solitary or in pairs. Note prominent golden hackles and grayish-based bill in all ages. Direct flight steady, with heavy, relatively shallow wingbeats usually ending on an upstroke; soars with wings in slight dihedral; glides on modified dihedral. Shape more buteo-like than Bald, with smaller head, longer tail. Ad from imm Bald by shape, flight style, and all-dark plumage with tawny upperwing bar, golden hackles. Cf. Turkey Vulture. Takes 4–5 years to attain ad appearance. Sounds: Not especially vocal, but pairs give agitated, repeated scratchy yelps. Status: Uncommon. N. populations migratory, moving mainly Mar–May, Oct–Dec; s. populations mostly resident. Also n. Mexico, Eurasia. Osprey Pandion haliaetus L 53–66cm, WS 149–171cm, Wt 1.0–1.8kg. Large, boldly patterned, long-winged raptor that hovers and plunge-dives for fish in coastal estuaries, lakes, and rivers; frequently carries fish in strong talons. Can be seen far from water during migration (e.g., over desert or mountains). Builds large, obvious stick nest on raised platform, pilings, utility poles, dead trees. Note distinctive white head with dark eyeline; crooked wings impart gull-like appearance in flight. From imm Bald Eagle by smaller size, lankier shape, boldly patterned flight feathers, and clean white body and underwing coverts. Cf. soaring large gulls. Juv has pale-fringed upperparts, orange eyes; like ad by 2nd fall. ♀s average more heavily marked (especially on breast). Caribbean ssp (ridgwayi); regular in Florida Keys, differs from widespread American (carolinensis) in being nearly wholly white-headed. Sounds: Vocal year-round; often heard high overhead while soaring. Display call a monotonous series of raspy, rising turee whistles (~1/sec) given by high-flying ♂ over territory. Guard call, given around nest, a measured series of whistled tew notes (~1/sec), often ending in raspy turee whistles. Alarm call, given year-round, a more rapid series of whistles (~5/sec), increasing then waning in intensity and pitch. Status: Common and increasing, especially on E Coast. N. populations migratory, moving mainly Mar–May, Aug–Nov; s. breeders mostly sedentary. Winters to S America. Also Old World. 254

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often some dark in head and tail

at a distance, head and tail “disappear”

often communal in winter

dusky bill markings

4th–5th-yr ad-like

Bald Eagle

plank-like wings held mostly flat

big head and long tail

All show golden hackles, gray-based bill

Golden Eagle

4th–5th-yr ad-like

larger than Turkey Vulture; flight steadier, less pronounced dihedral

often some whitish in tail base or wings

wavy gray bands

ad golden hackles can impart pale-headed appearance

tawny mottling

messy upperparts with tawny wingbar

Large, boldly patterned, gull-like, with crooked wings juv

glides on crooked wings

pale leading edge

feathered

small head and long tail juv has white-fringed upperparts, buffy wash below

Osprey

orange eyes

dark “wrist” patches Caribbean ssp (s. FL) mostly white-headed pale head

juv ad has yellow eyes

juv

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Swallow-tailed Kite Elanoides forficatus L 52–62cm, WS 119–136cm, Wt 325–500g. Large, graceful, and usually unmistakable raptor of SE river systems. Rarely seen perched. Hunts insects on the wing, floating effortlessly with little flapping; also snatches reptiles and amphibians from treetops in aerial stoops. Direct flight unhurried, with slow elastic wingbeats often interspersed with glides. Glides on bowed wings with “wrists” pressed forward (cf. Osprey, Magnificent Frigatebird). Sexes alike; ad longer-tailed than juv. Juv breast buffy when fresh, fading to white. Sounds: Shrill, emphatic whistled klee klee KLEE!, mainly on breeding grounds. Status: Fairly common across most of FL but local elsewhere in the SE. Trans-Gulf migrant mainly Feb–Apr, Aug–Sep; a few move through coastal TX. Large flocks stage in s. FL in late summer. Rare but regular n. of mapped range mainly Apr–May. Also to S America.

Mississippi Kite Ictinia mississippiensis L 33–37cm, WS 75–83cm, Wt 216–339g. Dark, falcon-shaped aerialist of s. riparian areas. Flies with subtle twists of wings and tail, limited flapping; captures insects on the wing. Often gregarious; large flocks occur during migration. Surprisingly like Peregrine Falcon when seen soaring at a distance but slimmer and more lightly built with narrower-based wings; tail slimmer, with narrow base, squared tip (broadbased and rounded tip on Peregrine). Direct flight languid, with harrier-like wingbeats, slower than large falcons; soars frequently on flat or bowed wings, not with shallow dihedral like Peregrine. Glides on bowed wings with “wrists” pressed forward, “hands” drooped and pointed. On ad note pale head, red eyes, whitish secondaries above, muted rufous wing flashes. Sexes similar; ♂ averages whiter head, blacker tail and primaries. Juv heavily streaked below; flight feathers variably barred, some with broad white bases. 1st-s has gray body but retains juv flight feathers. Attains ad appearance in 2nd fall. Sounds: On breeding grounds, a piercing 2-note whistle, 2nd note descending, pse-seeeeew. Status: Fairly common; local in river systems of the SW. Range expanding n. and w. Long-distance migrant, moving mainly Apr–May, Aug–Sep. Notable movements along TX coast. Imms and a few ads wander widely in spring, mainly May–Jun. Winters S America. White-tailed Kite Elanus leucurus L 36–41cm, WS 99–102cm, Wt 305–361g. Strikingly white, graceful raptor of open country, roadsides, and agricultural areas. Mostly solitary or in pairs, but sometimes forms winter roosts of 10s near optimal foraging areas. Habits recall kestrel: perches on wires and treetops, hovers frequently, and drops on prey items (mainly small mammals) from low–moderate heights. Hovers and stoops with wings in a steep V, legs dangling below slim body. Direct flight languid, with harrier-like wingbeats. Soars and glides with wings often held raised above body with flatter “hands.” Cf. ad ♂ Northern Harrier. Sexes similar, but ♀ averages darker above, grayer nape. Juv mottled brown above, washed and streaked rusty on breast (fades and molts to white by midwinter); tail has dusky subterminal marks (mainly May–Dec). 1st-spring like ad but with pale-fringed primary coverts; often retains juv tail. Attains ad appearance in 1st summer. Sounds: Main call an Ospreylike hew whistle; also a whistle-snarl, seee-grk, and a short, grating snarl. Status: Uncommon to fairly common but declining. Movements poorly understood; extensive post-breeding dispersal especially to coastal CA. Exceptional n. and e. of mapped range. Also s. to S America. hovers and stoops with wings held in a strong V

276

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Swallow-tailed Kite

ad ad

ad juv

with Mississippi Kite and Broad-winged Hawk

Mississippi Kite juv flight feathers variable

juv

whiter than ♀

1st-spring/s with Peregrine Falcon

long wings

ad ♂

1st-spring/s

ad ♀

tail slightly flared ad ♂

glides with drooped “hands”

White-tailed Kite juv

ad ♀

juv

usually grayer nape than ♂

ad ♂

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ad ♂

American Barn Owl Tyto furcata L 32–40cm, Wt 400–700g. Ghostly aerial hunter of open country, often coursing buoyantly over fields in search of small mammals. Favors lower-elevation open areas such as grasslands, agriculture. Striking combination of whitish underparts, buffy upperparts, heart-shaped facial disk, and dark eyes. Nocturnal but does hunt by day when food-stressed. Nests and roosts in cavities in earthen banks, cliffs, trees, as well as barns, nest boxes. Ages similar; downy chick white or gray with elongated reddish face, molts directly into ad-like plumage. Sexes differ: ad ♂ averages whiter below than ♀, often evident within pairs. Sounds: Vocal year-round. Flight call is an abrupt, blood-curdling, hissing screech, sheeeeeE, given at 15–30-sec intervals, sometimes coupled with soft wing claps during courtship; cf. begging calls of juv Great Horned Owl, which are more persistent, weaker, and given by stationary birds. Also gives a mechanical chitter and various purring and hissing calls, mainly near nest. Status: Scarce and declining in the East; common on s. Great Plains and in the West. Generally resident, but n. breeders move s. mainly Sep–Mar. Also s. to S America.

Burrowing Owl Athene cunicularia L 19–25cm, Wt 120–230g. Small, ground-dwelling owl often seen by day standing near nest (or roost) burrow or with just head and upper body exposed in burrow entrance. Takes cover in burrows when disturbed. Note long legs, upright posture. Hunts mainly small mammals and insects at night; perch-hunts and hovers. Favors dry grassland and farmland but also found in suburban areas, especially in FL, where it can be quite tame. Usually in association with burrowing mammals, which typically excavate its nest holes; FL birds usually excavate their own burrows. Nests in loose colonies or single pairs. Sexes similar, but ad ♂ obviously paler than ♀ during breeding season due to increased bleaching/wear. Ages differ; juv molts into ad-like plumage by fall. Florida ssp (floridana) has speckled underwings and averages smaller and more contrasty than widespread Western (hypugaea). Sounds: Song given by ♂ in spring (Mar–Jun) a simple piping wo-hoooo. Various chatter calls given in alarm—often the only calls heard during migration/winter. Juv gives extended begging rasp. Status: Uncommon to locally common. Resident in FL; migratory in the West, moving mainly Feb–Apr, Sep–Nov. Rare vagrant to the East. Also s. to S America. Snowy Owl Bubo scandiacus L 60–71cm, Wt 1.58–2.95kg. Large, mostly white Arctic owl that irregularly reaches Lower 48 in winter. Nearly unmistakable, but cf. American Barn Owl, paler populations of Great Horned Owl, albino hawks. Prefers barren landscapes that mimic tundra breeding grounds such as beaches, airports, marshes, wetlands. Often perches on ground or man-made structures (e.g., rooftops, poles, towers), sometimes in urban areas. Hunts by day, especially early and late. Eats small mammals, medium-size birds (e.g., ducks), captured on the wing or from a perch. Mainly solitary but can gather in groups in areas of high prey density. Ages, sexes differ: in general, ♂s whiter than ♀s; ads whiter than juvs. Juvs sexed by wing/tail pattern. Aged up to 4th-w by molt patterns in primaries/secondaries. Sounds: On breeding grounds, gives very low, guttural hooo, usually in pairs or a short series. Also a high-pitched screaming whine. Rarely heard away from breeding grounds. Status: Nomadic; takes advantage of abundant prey populations regionally. Regular in winter mainly Nov–Mar s. to Puget Sound (WA), n. Great Plains, Great Lakes; rare elsewhere except during irruptions (often every 4 years but varies by region). Exceptional to CA, s. Great Plains, and the SE, and in summer s. of the Arctic. Circumpolar.

often roosts in snowy dunes in winter

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American Barn Owl

Strikingly white below, pale above

Burrowing Owl low, undulating flight

Florida ad ad ♂ averages whiter below

ad ♀ Western ad ad with juvs; ♂ br often sun-bleached

Snowy Owl

ad ♀ mostly white by 3rd winter imm ♂

juv ♀ averages most heavily marked

many new secondaries 3rd-w ♀ aged by worn ad P6–P7

fresh inner secondaries

2nd-w ♀

1st-w ♂

♀ has barred flight feathers, many tail bands

aged by fresh P7–P8

♂ has lightly spotted flight feathers, fewer tail bands

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ad ♂

Barred Owl Strix varia L 43–50cm, Wt 470–1050g. Large, dark-eyed owl of mature woodland, swamp, forest edge; lacks ear tufts. From Spotted Owl by streaked belly and barred upper breast and throat; voices differ. Perch-hunts mammals, birds, reptiles, amphibians. Mainly nocturnal but often active during morning. Versatile nester, often in tree cavities. Sexes similar. Ages differ: juv fluffy white with coarse black barring; barring averages buffier above but most not safely separable from ad by 1st fall. Beware hybrids with Spotted where ranges overlap. Hybrids show mixed characters but generally look like darkbacked Barred with confused pattern below. Sounds: Vocal year-round and often during the day. Song the classic 2-phrase hooting, who-cooks-for-you, who-cooks-for-you-all; also gives ascending series of short hoots. Pairs duet and often ascend into a raucous cackling. Also a rising, screaming, whistled sweeeEEEE! and a piercing hoooo-awwwwww, descending at the end. Fledgling gives long, rising hiss recalling American Barn Owl flight call but weaker, longer, more rising. Status: Fairly common resident e. of Great Plains; common in the SE; uncommon but increasing in the West, especially Pacific NW, where it is displacing Spotted. Spotted Owl Strix occidentalis L 46–48cm, Wt 449–850g. Iconic dark-eyed owl of old-growth forest in Pacific NW, redwood and oak forest on Pacific Coast, and dense oak and mixed-conifer forest in the SW. Cf. Barred Owl. Nests in broken snags, cavities, old stick nests. Mainly nocturnal. Perch-hunts small rodents. 3 ssp barely distinguished by average overall plumage color and prominence of white spots. Northern (caurina) and California (occidentalis) ssp similar, but California slightly paler above with more prominent white spots. Mexican (lucida) paler above and has more prominent white spotting below. Sexes similar. Ages differ: juv fluffy, light brown, barred darker. Sounds: Song a slow-paced nasal woo, woo-hoo, hoooo, sometimes with a few extra introductory notes. Also an ascending hoot series and high-pitched upslurred, screeching whistle, similar to Barred. Interacting pairs give various barking, clucks, coos, and whistles. Fledgling gives long, rising hiss similar to juv Barred. All ssp sound similar. Songs of Spotted × Barred Owl hybrids sound intermediate and confused. Status: Uncommon to rare in the Pacific NW; fairly common but local throughout remainder of range. Generally resident, though small-scale movements (mainly elevational in the Interior West) occur. Also Mexico.

Great Gray Owl Strix nebulosa L 61–84cm, Wt 700–1700g. Very large, stately owl of boreal forest and w. mountains, encountered mainly during irruptions away from breeding areas. Prefers edges or openings in forest, bogs, meadows. Mainly crepuscular and nocturnal but also hunts by day when food is scarce. Perch-hunts small mammals, even pouncing through deep snow to seize prey. Flight with slow, heavy wingbeats and long glides; quick direction changes and brief hovering when hunting. Nests in abandoned raptor nests, broken-off tree trunks, and other platform-like surfaces. Sexes similar. Ages differ (see p. 285): juv grayish with faint darker bars. Sounds: Song a series of 6–10 deep, wellspaced hoots (1–2/sec). Also a single rising woooOOO! When agitated, a variety of chattering squeaking calls. Begging fledgling gives quick, rising sweeEEE! Status: Scarce. Nomadic; follows prey populations regionally. Periodically irrupts into Lower 48, mainly in Great Lakes region, rarely as far e. as New England. W. populations more sedentary, though some move to lower elevations in winter. Also n. Eurasia.

plunges into deep snow when chasing prey

292

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Barred Owl

Big and dark-eyed; barred breast, streaked belly

juv

complex underparts pattern; dark back

Spotted × Barred Owl hybrid

Spotted Owl

Dark eyes, spotted belly large white spots

juv

smaller spots

Mexican ad rusty vent

white-bellied appearance

Pacific NW/CA ad

Mexican ad

Huge and scarce; big, round head, staring yellow eyes

narrow gray lines on face

Great Gray Owl

white “bow tie”

1st-w

grayer when fresh

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worn ad summer

Chuck-will’s-widow Antrostomus carolinensis L 29–33cm, Wt 70–140g. Large nightjar, commonest in the South. Occurs in moist mixed conifer and broadleaf woodland, often near clearings. Roosts mainly in trees and bushes, less often on ground; hunts and sings mainly from perches at mid–upper levels. Note large size, big and often rather anvil-shaped head, very long wings. Plumage warmer and less contrasting overall than Eastern Whip-poor-will, but ♂ tail pattern striking (shows above only on spread tail). Eastern Whip smaller, shorter-winged; plumage patterns often more contrasting overall, with more silvery and blackish elements; throat dark (especially ♂); crown often has broad black median stripe; note tail patterns. Ad ♂ has large white tail patches; ad ♀ has broad cinnamon tail corners; 1st-yr (both sexes) has diffuse cinnamon tail tip. Sounds: Song a slightly burry, clipped chk wídu-wídu, ~1 phrase/1.5 secs; 1st note quieter. Also a low, whispered, burry series, khow-khow-khowkhow …, and a more growling bark series when agitated. Status: Common in the South; uncommon but spreading to the n. Migration mainly mid-Mar–Apr in s., Apr–early May in n., Aug–early Oct. Winters s. to Caribbean and nw. S America. Eastern Whip-poor-will Antrostomus vociferus L 23–24cm, Wt 43–64g. Sings name incessantly on summer nights in the East. Occurs in larger tracts of drier wooded habitats with open understory. Roosts in trees and on ground; hunts and sings mainly at forest edge and in adjacent clearings, from ground to subcanopy. Cf. larger, longer-winged Chuck-will’s-widow. Ad ♂ has large white tail patches (sometimes tinged buff at tips); 1st-yr ♂ has smaller white tail patches; ♀ has buff tail tips. Sounds: Song a faintly burry, whistled whih p-wiéu, ~1 phrase/sec, last note carrying farthest; clearer-toned than Mexican Whippoor-will. Low burry series like Chuck-will’s-widow but faster, interspersed with distinct clicks. Also a clucking, liquid pwip when agitated. Status: Common to fairly common but declining. Migration mainly late Mar–early May, Aug–Oct. Winters s. to Cen America. Mexican Whip-poor-will Antrostomus arizonae L 23–24cm, Wt 45–50g. Counterpart to Eastern Whip-poor-will in sw. mountains. Occurs in conifer, pine-oak, and oak forest, especially canyons. Note relatively dark plumage with paler and grayer crown sides and scapulars, tail pattern; often shows variable rusty hindcollar. Cf. very local Buff-collared Nightjar. Eastern Whip (vagrant in the West) averages colder-toned (especially ♀); ad ♂ averages more white in tail, ♀ has darker throat than Mexican; silent birds rarely separable. Mexican ad ♂ has large white tail patches; 1st-yr ♂ has smaller white tail patches; ♀ has buff tail tips. Sounds: Song a strongly burry, whistled c-wurr p-wuín, ~1 phrase/1.0–1.5 secs; 1st note soft, inaudible at a distance. Clucking, burry gwip when agitated. Status: Common to fairly common Apr–Sep, stragglers rarely later. Also s. to n. Cen America. Buﬀ-collared Nightjar Antrostomus ridgwayi L 22–23cm, Wt 40–61g. Very local summer visitor to rocky desert canyons of se. AZ. Roosts mainly on ground; hunts and sings from ground and perches, often at mid–upper levels in bushes and trees. Note relatively pale grayish plumage with cinnamon hindcollar (varies with angle of view, and beware Mexican Whip-poor-will often has variable rusty collar), tail pattern; cf. darker, less compact Mexican Whip and smaller, more compact Common Poorwill. ♂ has large white tail patches only reaching outer edge at tip (1st-yr ♂ Mexican Whip similar); ♀ has buff tail tips. Sounds: Song striking, an accelerating, slightly rising or overslurred series of hollow clucks ending with emphatic note, ku-ku-kukukukukuku-chía and variations, every 1–2 secs or, when excited, run together with barely a pause between songs. Low chuuk when agitated. Status: Sporadic and local Apr–Sep (most records May–Jul) in se. AZ, rarely adjacent sw. NM. Also s. to n. Cen America.

300

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Chuck-will’s-widow

Large, long-winged nightjar, commonest in the South

big head

migrants may be seen flying over ocean

ad ♀

1st-yr

warm brown cheeks and throat

ad ♂

crown striping variable; cf. Eastern Whip

♀

long wings

white only on inner webs

Eastern Whip-poor-will

Drier e. forests broad dark stripe

1st-yr ♂ ad ♀

downy chick cinnamon (Chuck similar)

crown striping variable; cf. Chuck

dark throat

ad ♀

ad ♂

more white than Mexican Whip

Mexican Whip-poor-will

Sw. mountains

longer than Eastern

broad dark stripe

1st-yr ♂

forecollar varies with pose

ad ♀

ad ♂

ad ♀

Buff-collared Nightjar

Very local in se. AZ desert canyons cinnamon hindcollar

forecollar varies with pose ad ♀

paler and grayer than Mexican Whip

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ad ♂

KINGFISHERS: Alcedinidae. Diverse worldwide family of small to large birds that occupy wet and forested habitats; in N America, strongly linked to water. All share stocky build, large head, and long, heavy, pointed bill. Plunge-dive from perches or hover and dive to catch prey beneath the surface, mainly fish. Fly with distinctive rowing wingbeats that nervously double in speed every few seconds. Nest in burrows in mud banks. Solitary except when breeding; defend territories with simple vocalizations, mainly loud rattling flight calls. Belted is widespread; the others share primarily tropical distributions, barely reaching the US-Mexico border. Typically identified easily by plumage, range. Ages, sexes differ. 3 regular species, 1 vagrant.

Belted Kingfisher Megaceryle alcyon L 28–33cm, Wt 113–178g. Big, boldly patterned, and always fun to watch; the only regularly occurring kingfisher across most of N America. Conspicuous and noisy when present; breeds in cavities near a variety of fresh and brackish habitats, including rivers, streams, lakes, estuaries; occurs in saltwater habitats mainly in migration, winter. Can occur far from water on migration. Note large head with shaggy crest, short tail and legs, bold plumage. Ad ♂ lacks ♀’s orange-rusty breast band. Juv has rust mixed into upper chest band/flanks May–Dec; some retain brownish mix through 1st spring. 1st-s has worn wings, retained juv wing coverts. Sounds: Typical far-carrying call a low, clattering rattle given repeatedly in flight and territorial defense. Also screechy whining near nest. Status: Common. N. populations migratory mainly Mar–May, mid-Aug–Oct. Hardy; overwinter anywhere open water persists. Winters to s. Cen America, Caribbean. Ringed Kingfisher Megaceryle torquata L 38–42cm, Wt 254–325g. Large, big-headed, and big-billed kingfisher of s. TX freshwater habitats, especially Rio Grande region. All plumages from Belted by extensive rufous underparts. Ad ♀ has blue and white bands across chest; ad ♂ has blue partial collar. Juvs similar to ad ♀; juv ♂ has little/no white breast band, reduced rufous on underwing coverts; like ad by 1st winter–spring. Sounds: Typical rattle call louder, slower, more machine-gun-like than Belted, often more protracted (1–20+ secs). Common flight call, a deep single rruk, draws attention to birds high overhead. Status: Uncommon but expanding n. in TX. Rare vagrant to s. Great Plains, w. Gulf Coast, mainly late fall–winter. Also to S America. Green Kingfisher Chloroceryle americana L 18–20cm, Wt 29–55g. Small, inconspicuous kingfisher of quiet overgrown freshwater streams, ponds; restricted to s. TX, s. AZ. Perches low, often in cover. Unlikely to be confused with others if seen well but often flushes quickly, giving fleeting views, flashing white tail edges. Flies low, fast, and direct; does not hover. Unlike the other two kingfishers, ad ♂ is more colorful than ♀, with orange breast band. Ad ♀ has spotted green double breast band, often incomplete; throat and middle breast buffy, especially when fresh. Juv generally like ad ♀, but juv ♂ can show orange breast sides rather quickly; like ad by mid-fall. Sounds: Soft but sharp clicking calls, like 2 stones being tapped together, given by perched or flying birds; sometimes run together in short rattle. Also a hard, nasal downslurred buzz, dzrrt, and a grating chatter mainly in interactions. Status: Uncommon in TX; sporadic in se. AZ. Also to S America. TROGONS: Trogonidae. Diverse and colorful pantropical cavity-nesting birds. Ages, sexes differ; like adult in 2nd year. 1 species regular in AZ, 1 vagrant.

Coppery-tailed Trogon Trogon ambiguus L 28–30cm, Wt 60–79g. Spectacular summer resident of shady canyons of se. AZ “sky islands,” this species offers birders a taste of the tropics. Favors mature streamside trees, especially sycamores, where it perches quietly in the mid-story, slowly turning head in search of food. Sallies to pluck fruits, insects, small reptiles from foliage, often hovering briefly, the ♂ flashing its brilliant red and green colors. Juv dusky brown with spotted wing coverts; mostly like ad by late fall but retains juv tail through 1st year. Sounds: Both sexes sing a series of 5–10 guttural, 1- or 2-syllable notes, kwirkwir-kwir-kwir …, recalling Wild Turkey calls. Also a more growling variation, often delivered at faster pace, and a short, squirrel-like chuckle when alarmed. Status: Uncommon and local. Mostly migratory; a few birds winter in breeding canyons, surrounding lowlands. Migration mainly mid-Apr–May, late Aug–Sep. Rare vagrant to NM, TX, mainly winter. Also Mexico. 318

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Belted Kingfisher

Only kingfisher across most of N America juv ♀ (May–Oct)

rowing wingbeats interspersed with erratic double-speed flaps

juv ♂ (May–Oct)

ad ♀

Belted and Ringed hover high above water, dive headfirst for fish

ad has plain wing coverts ad ♂

Ringed Kingfisher Scarce; mainly

Restricted to s. TX

juv ♀

se. AZ

ad ♀

complete blue, variable white bands

Coppery-tailed Trogon

juv (Jun–Sep) 1st-w ♂ (Nov–Apr)

juv ♂ has white greater coverts [May–Dec] partial blue band

underwings rufous (white on ad ♂)

ad ♂

ad ♀

Green Kingfisher

Restricted to s. TX, se. AZ; small and inconspicuous wing coverts tipped white

bold white

juv ♂ (Apr–Oct)

washed orange on ♂

ad ♂

variable spotted double breast bands ad ♀

ad ♂

Trogon not to scale For general queries, contact info@press.princeton.edu.

flies with deep undulations

Acorn Woodpecker Melanerpes formicivorus L 19–23cm, Wt 65–90g. Conspicuous “clown-faced” woodpecker of foothills and montane woodlands in Pacific states and the SW. Strong preference for pine-oak woods; rare away from oaks. Often flycatches. Cooperative breeder living year-round in family groups. Stores acorns in specialized trees (also utility poles) called granaries. Pacific birds average longer-billed, often with broader breast band and less streaking on flanks than birds of the SW, but much individual variation. Ad ♀ has black forehead. Sounds: Noisy; often detected by loud, raucous calls. Common calls include a nasal repeated whaka, usually rising and falling in tempo and loudness; a nasal gaaaarick; a rolling karrrit-ut, sometimes abbreviated; and a nasal urrk, suggesting a nutcracker. Drum variable; usually short, slow and accelerating. Status: Common resident; rare CO’s Front Range and TX Hill Country; exceptional to Great Plains, Gulf Coast. Also locally s. to n. S America. Lewis’s Woodpecker Melanerpes lewis L 25–28cm, Wt 88–122g. Distinctive woodpecker of open riparian and oak habitats in the West, usually found perched atop utility poles, dead snags, or old cottonwoods. Often flycatches, engaging in long glides and aerial acrobatics. Usually found in small groups. No species similar, but high-flying migrants may be dismissed as a small crow. Sexes alike. Juv dull, almost entirely dusky gray and black; quickly acquires ad-like plumage, but some retain a few brownish juv feathers into Dec, occasionally later. Sounds: Fairly quiet. Call a simple yik (♂) or yik-ik (♀). ♂ gives harsh, repeated churr, sometimes called a song. Drum infrequent, relatively short and weak, sometimes followed by taps that suggest sapsucker. Status: Uncommon and fairly local. Migration mainly May, Sep–Oct; somewhat irruptive. Wandering birds, mainly Oct–May, rarely to Great Plains and cen. TX; exceptional to Great Lakes and the NE. White-headed Woodpecker Leuconotopicus albolarvatus L 20–23cm, Wt 53–68g. Stunning woodpecker of mixed coniferous forest in the West, favoring areas with ponderosa and other pines with large cones. Often forages on pine seeds, particularly in fall–winter; also probes terminal clusters of needles and flakes bark; rarely drills deep into wood to forage. S. birds longer-billed (♂s > ♀s throughout range), perhaps driven by preference to forage on huge Coulter pine cones (mostly ♂s) and thick-barked lower trunks (mostly ♀s). Ad ♂ has small red patch on hindcrown, usually visible. Juv duller with variable orange-red patch on crown. Sounds: Call a sharp pi-deek (usually 2–3 notes), similar to Nuttall’s Woodpecker but higher and with a squeaky quality like Hairy Woodpecker. Rattle similar to Hairy but without squeaky introductory note. Drums mostly winter and spring, intermediate in rate between Hairy and Downy Woodpeckers, slower than Ladder-backed Woodpecker. Status: Uncommon to locally fairly common resident; wanders locally in fall–winter. Williamson’s Sapsucker Sphyrapicus thyroideus L 20–23cm, Wt 44–55g. Uncommon woodpecker of w. mountains, favoring Douglas-fir, ponderosa pine, and western larch. Occurs less frequently across wide variety of other conifer and mixed-conifer forests. Often nests in nearby aspen. ♂ and ♀ strikingly different (initially described as different species). ♂’s black upperparts unique among sapsuckers. ♀’s brown head, dark finely barred back, and yellow belly distinctive. Juv of each sex duller, quickly acquiring ad-like plumage; some retain a few dull juv feathers into winter. Sounds: Typical call is a nasal mew with much more vibrant harmonic structure than other sapsuckers (rarely more pure-toned). Also a repeated squealing quee-rr call, longer and slower than other sapsuckers. Distinctive drumming has 5+ sets of tapping. Status: Uncommon to locally fairly common resident or breeder. Rarely detected as a migrant, mainly late Mar–early May, Sep–Oct. Uncommon in winter in Lower 48. Exceptional in East. Winters to cen. Mexico.

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Lewis’s Woodpecker

Acorn Woodpecker Large; glossy black

Distinctive; “clown” face

with pink belly

white rump

crow-like flight

often flycatches from snag

♂

juv

ad ad ♂

juv (Jun–Sep) silvery collar ad

ad ♂ ad ♀

Pacific Slope birds average longer-billed with broader breast band

1st-fall (Sep–Nov)

White-headed ♀ finely barred, brown Woodpecker head

Black with white head and wing patches

ad ♂

juv ♀ (Jun–Aug)

Williamson’s Sapsucker

brown

♀

juv (Jun–Sep)

barred

ad ♀ ad ♀

1st-fall ♀

some with reddish throat

ad ♂ ad ♂

black

ad ♀

juv ♂ (Jun–Oct) For general queries, contact info@press.princeton.edu.

CROWS AND RAVENS. Corvus. Familiar all-black birds found in a wide range of habitats across most of the continent. Highly intelligent and social; can occur in flocks year-round, sometimes 100+ (ravens) or 1000+ (crows). Identify by range, structure, voice. Juveniles have browner, loosely textured plumage, replaced in late summer–fall; by spring, 1st-year birds have faded brown flight feathers (sometimes very worn) contrasting with newer glossy-black wing coverts and body. Diverse array of sounds complicated by age-related variation: juveniles have higher, more nasal calls than adults through early fall. Sexes similar, but males average larger. Common Raven (left), American Crow (right)

raven more raptor-like in flight than crow

with Red-tailed Hawk

raven has longer wings and tail than crow

ravens soar frequently, often with raptors

Common Raven Corvus corax L 58–69cm, Wt 689–1625g. Largest corvid; deep croaking voice. Favors mountains, boreal forest, some coastal, rural, and suburban areas. Highly aerial, often soars in pairs, sometimes larger “kettles.” Patrols low over roads on rowing wingbeats (shallower than crows) in search of carrion; flocks gather at carcasses. In open areas, often nests on utility poles; large stick nests conspicuous. Very similar to Chihuahuan Raven. Cf. American Crow. N. populations average larger. Sounds: Highly varied calls more croaking and resonant than crows, including a burry caw (lower, coarser than American Crow) and a deep, resonant rook, both given singly or in short series. Many variations. Pacific Coast birds average higher, softer. Juv calls varied; generally, an upslurred, screaming raaaa, with a goat-like quality. Status: Common in the West; local but increasing in the NE. Mostly sedentary; exceptional outside mapped range. Also to Cen America, Eurasia. Chihuahuan Raven Corvus cryptoleucus L 46–53cm, Wt 380–670g. Rangerestricted raven of grassland, desert scrub, towns, orchards in the SW. Best told from Common Raven by voice and structure. Chihuahuan has shorter bill, averages longer nasal bristles, often has flatter crown peaked at rear, and has whitebased neck feathers vs. grayish in Common (tricky to assess in harsh lighting). Chihuahuan is smaller, more compact, with shorter neck, slightly shorter wings, often more rounded tail, and more buoyant, crow-like flight. Where sympatric, Common more likely in foothills, mountains but often enters Chihuahuan habitat. Some individuals best left unidentified. Sounds: Much less variable than Common; most calls are a short, nasal, upslurred raaa or raak, almost duck-like (cf. longer, more screaming juv Common). Not known to give deep rook calls. Status: Common within limited range; exceptional n. of mapped range. Mostly sedentary but concentrates locally in nonbreeding season. Also n. Mexico.

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Common Raven

Larger and bigger-billed than crows, deeper voice

long, swept back

juv

(Mar–Sep)

long neck, head

Common

long, graduated

shaggy

grayish feather bases

ad Chihuahuan

whitish feather bases

averages longer nasal bristles than Common

Chihuahuan Raven shorter, broader than Common

Desert grasslands; smaller, more compact, shorter-billed, puffier nape than Common

often more rounded than Common shorter neck, head

more front-heavy than Common ad

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SMALL GREEN-AND-RUFOUS GORGETED HUMMERS: Selasphorus. Four western species that are mainly birds of mountains and the Pacific Coast. All have variable orange sides, some orange in tail. Tapered outer primaries of adult males in 3 larger species produce wing trill in direct flight (but not when hovering). Wing molt mainly September–May. Females average larger, longer-billed than males and have broader tail feathers.

Rufous Hummingbird Selasphorus rufus L 8–9cm, Wt 2.8–4.5g. Commonest rufous-colored hummingbird, breeding in open woodland, gardens, shrubby vegetation. Notably aggressive, chasing off larger species such as Anna’s Hummingbird. Ad ♂ almost always has diagnostic rufous on upper back; ♀/ imm rarely distinguishable in the field from Allen’s Hummingbird except by range, season, and ♂ dive display (made by imms of both species as early as May): ♂ Rufous repeats high, J-shaped dives several times vs. single, steeper J dive of Allen’s, which is preceded by shallow rocking arcs. Rectrices of Rufous broader than Allen’s by age/sex, and R2 tip has distinct notch on ♂ Rufous (and some ♀s). ♀ and imm Rufous/Allen’s have rufous body sides, typically forming distinct “vest” that contrasts with white forecollar; flanks often fade to pale wash in fall–winter, rarely with some green flecks. Tail and throat patterns of Rufous/Allen’s help determine age/sex: imm has throat with neat lines of dark flecks or distinct spots vs. plainer throat with solid central flame patch on ad ♀. Imm ♂ has more extensive rufous tail base than imm ♀. Attains ad plumage over winter, with gorget last to molt. Some imms in fall can be difficult to separate from Broad-tailed Hummingbird, which is slightly larger and bigger-tailed, with higher chip call, and differs in several plumage features, but much overlap (cf. Broad-tailed). Sounds: All sounds similar to Allen’s. Chip a fairly hard clicking tik or chik; similar to Anna’s but averages lower, less smacking. Aggressive calls a nasal jiuw and a buzzier zziirr. Chase calls include a warning buzz note followed by rapid twitter, zziir tí-tíchip tí-tíchip and variations, typically with jerky rhythm. ♂ produces low, stuttering ch-ch-ch-ch-chi at bottom of J-shaped dive. Ad ♂ wing trill higher than Broad-tailed. Status: Common. First migrants arrive in Feb; ad ♂s move s. by late Jun–Jul, with most birds departing by Oct. Fall migration (mainly Jul–Sep) more easterly and through mountains than more coastal spring route (mainly Feb–Apr). Rare in the NE mainly Jul–Nov, some lingering to winter; rare but regular in the SE mainly Aug–Mar; in winter, very rare in CA and AZ. Winters mainly w. Mexico. Hybrid zone with Allen’s along 300 km of coastal s. OR and n. CA compounds ID issues. variations in R1 pattern of ♀/imm Rufous/Allen’s

imm ♂

imm ♀

ad ♀

Allen’s Hummingbird Selasphorus sasin L 8–9cm, Wt 2.4–3.8g. Replaces Rufous Hummingbird as a breeder in CA and breeds/molts earlier; usually not as aggressive around feeders. Ad ♂ always green-backed but with extensive rufous rump; outer rectrices narrower than Rufous, and R2 lacks distinct notch at tip. ♀/imm rarely distinguishable in the field from Rufous except by range, season, ♂ dive display (given by imm ♂s as early as May); see Rufous for dive descriptions and age/sex criteria. Many birds best recorded simply as “Rufous/ Allen’s.” Ad ♀ of resident s. CA population has paler rufous sides spotted green, whereas migratory population typically has brighter rufous sides lacking green spots. Sounds: Like Rufous except for drawn-out whine when pulling out from deep J dive, and stuttering z-z-zzir at reversals of pendulum rocking, which attracts attention once learned. Status: Common. First migrants arrive Jan; most depart by early Sep (ad ♂s depart n. breeding grounds by late Jun–early Jul). Fall migration (mainly Jun–Aug) more easterly than largely coastal spring route (mainly Jan–Mar). Very rare in the East Aug–Mar. Resident population on Channel Islands and adjacent s. CA coast; migratory population winters cen. Mexico. 350

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Allen’s Hummingbird

Rufous Hummingbird

bright rusty, often with a few green spots

repeated sloping J dives

gorget often looks blackish

ad ♂

green back variable on Allen’s, ad ♂ Rufous rarely has green back; ID by tail features

ad ♂

rufous upper back feathers diagnostic by mid–late winter

always has green back

single steep J-shaped dive preceded by rocking arcs ad ♂

imm ♂ (Oct–Mar)

narrow, wire-like

ad ♂

relatively broad

evenly tapered

notched tip

Rufous/Allen’s Hummingbirds to species in the field; note throat pattern, tail details

ad ♀s have whitish throat with central flame patch

imm (Apr–Oct) has variable flecked throat; sex best told by tail pattern

ad ♀

Rufous

imm ♂ (Apr–Oct)

faded plumage

fresh plumage

♀s and imms rarely identifiable

imm ♂s

Allen’s

narrowest R2 notched

imm ♂

no notch Rufous

broadest

ad ♀ of resident s. CA population has paler sides with green spotting (not shown by Rufous)

imm ♀s

Allen’s imm ♀ rarely lacks rusty rump fringes

imm ♀ (Apr–Oct) Rufous has broader feathers by age and sex, but imm feathers broader than ad For general queries, contact info@press.princeton.edu.

imm ♀

Barn Swallow Hirundo rustica L 12.5–14.5cm (+ 2.5–3.5cm tail streamers), Wt 17.0–20.7g. This elegant species is a familiar sight in open country near water, favoring farmland, marshes, lakeshores, towns. Nests in small colonies or single pairs, almost exclusively on man-made structures; places cup-shaped mud nests in barns, under bridges, building eaves. Note distinctive forked tail, longest in ad ♂, shortest in juv; buff underparts, darkest in ad ♂, palest in juv. Direct flight is level and fast, with clipped wingbeats, swept-back wings, short glides; often hunts low over ground or water, flashing white tail spots when it turns and flares tail. Small population breeding in Argentina in austral summer may appear in N America and be recognizable May–Aug by very worn plumage, primary molt. Some Eurasian birds (rustica and gutteralis; rare in AK) have whiter underparts, longer tail streamers than American (erythrogaster); breast band distinctly broad in rustica. Rarely hybridizes with Cliff Swallow; hybrids variable but usually have buffy rump, shallow tail fork, white tail spots. Sounds: Calls include a husky vit and vi-dit. Song a rapid, squeaky chatter dominated by vit notes. Status: Common. Migration mainly Apr–May, Aug–Sep; averages earlier in the East. Also Mexico; winters to S America, rarely s. US (increasingly in s. CA). Also Old World. Cliﬀ Swallow Petrochelidon pyrrhonota L 12.5–14.0cm, Wt 19.6–23.6g. Gregarious species; nests in large colonies in open country near water, grasslands. Clay-pot nests packed tightly together under cliff overhangs, highway overpasses, culverts, building eaves; adaptation to nesting on man-made structures has enabled e. expansion. Note contrasting buffy rump patch, squarish tail, mostly dark head set off by pale grayish collar; cf. Cave’s dark cap set off by orange-buff throat and cheeks. Flight rather floating with much gliding, some soaring. Mexican (melanogaster; SW, sparingly to Gulf Coast) has dark rusty forehead; intergrades with Northern (pyrrhonota Group) frequently. Juv much drabber than ad, with brownish upperparts, paler rump (nearly whitish when worn), dusky head with highly variable white mottling on throat/face, often rufous forehead. Some juvs solid rufous on throat, suggesting Cave, but throat darker than rump (vs. same tone or lighter on Cave), less contrasting lores. Sounds: Calls include a nasal new and harsh jrrr (cf. some Northern Rough-winged Swallow variations). Song a soft, protracted jumble of scratchy squeaks and “stretching rubber” sounds. Status: Common in the West; more local e. of the Appalachians. Migration timing varies regionally; mainly Apr– May, Aug–Sep, but earlier (Feb–Apr, Jul–Aug) in the SW, CA; lingers well into Oct along the Gulf Coast. Winters mainly S America. Cave Swallow Petrochelidon fulva L 12.5–14.5cm, Wt 14.7–24.2g. Close relative of Cliff Swallow, enjoying similar success adapting to man-made structures. Nests and roosts in limestone caves, sinkholes, as well as highway overpasses, culverts, buildings. Nest similar to Cliff’s but usually more bowlshaped. From Cliff by clean orange-buff throat and cheeks contrasting with neat dark cap; molts flight feathers during late summer (ads) and fall (imms), while Cliff does so on wintering grounds. Juv much drabber than ad, with brownish upperparts, weaker head pattern, variable dusky cheek and breast band; note contrasting dark lores, throat as pale or paler than rump. Caribbean ssp (fulva Group) averages smaller and darker overall than Texas (pallida), with deeper rust rump, darker and warmer-toned breast and flanks (flank streaks often obvious), contrasting rust rear cheeks (vs. more even-toned buffy in Texas); some overlap. Sounds: Calls include a nasal new (similar to Cliff) and rising whistled weet (cf. huskier Barn). Song similar to Cliff but incorporates distinctive “clicking-typewriter” series. Status: Caribbean ssp local in s. FL mainly mid-Feb–Sep, rarely straying to the NE Apr–May. Texas ssp common; migration mainly Feb–May, Sep–Nov. Texas ssp wanders widely: regular to the Great Lakes and NE, sometimes in the 100s, late Oct–early Dec (sometimes into Jan), rarely Mar–May; regular to FL Oct–May, possibly later; rare to CA, s. Great Plains; exceptional to the NW. Also Mexico, Caribbean; winters to Cen America.

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Barn Swallow

Long forked tail, variable buffy underparts juv (May–Nov)

ad ♀ ad ♂

ad ♂

paler underparts, shorter tail than ♂

white spots

juv

Cliff Swallow

Buffy rump, square tail, mostly dark head Northern juv buffy juv rufous

paler birds can recall Cave paler juv

rufous juv

variable white mottling

buff to whitish

Northern ad Mexican ad

Northern ad

juv (May–Nov)

Cave Swallow

Buffy rump and throat, square tail, neat dark cap Texas 1st-fall Texas ad

Texas juv

molts primaries during fall migration juv (May–Nov) darker juv

Caribbean ad Texas ad

drabber than ad; smudgy cheek patch

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averages darker, more richly colored than Texas

Caribbean ad

SHRIKES: Laniidae. Medium-size predatory songbirds neatly patterned in gray, white, and black. Largeheaded with thick neck, rounded wings, and long, graduated tail, often held closed. Nicknamed “butcher birds,” shrikes use their strong, hooked bills to capture birds, insects, lizards, small mammals, then impale and cache prey on a thorn or barbwire fence. Often solitary, or in pairs when breeding. Favor open areas, often perching conspicuously on roadside wires, fenceposts, treetops; often bob tail loosely. Flight low, fast, and undulating, with quick bursts of rapid wingbeats (cf. Northern Mockingbird, which has slower wingbeats, more level flight path); swoop up to perch; occasionally hover when hunting. Sexes similar; ages differ. Highest diversity in Old World. 2 species regular, 2 vagrant.

Loggerhead Shrike Lanius ludovicianus L 18–22cm, Wt 43–54g. Conspicuous bird of open country, especially across the West and the SE. Hunts from perches in a variety of sparsely vegetated habitats, including roadsides, agricultural areas, even barren lands and suburban areas. Ranges farther s. than larger and longer-tailed Northern Shrike and generally encountered more frequently by birders. May be confused with Northern Mockingbird at a distance, but note more contrasty plumage, thicker build, larger head, stouter bill, smaller white wing patches, faster undulating flight. ♂s average whiter below. Ads have uniform black wing coverts and flight feathers with broad white primary bases. Juv washed brown, has pale wingbar, faintly barred below; like ad by fall; some have pale bill base in 1st fall (cf. Northern Shrike). Geographic variation subtle: n. and w. populations average darker above; n. Channel Islands, CA, residents darkest dorsally; San Clemente Island, CA, residents average darkest above, whitest below. Sounds: Varied song consists of simple harsh or musical notes and short trills; repeats identical phrases every 1–2 secs, then switches. Also repeated, harsh vireo-like scolding calls. Status: Fairly common to uncommon and generally declining; nearly extirpated as a breeder from the NE. Migration mainly Mar–Apr, Aug–Nov. N. Great Plains breeders winter in s. TX and Mexico and perhaps augment populations elsewhere in winter. Also Mexico. Northern Shrike Lanius borealis L 23–25cm, Wt 56–80g. Large, robust shrike; breeds sparingly across the Far North, range overlapping only locally with similar Loggerhead Shrike in winter (mainly in the West). Prefers slightly more wooded habitat than Loggerhead, especially shrubby thickets, forest edge, bogs. From Loggerhead by larger size and rangier build, overall paler plumage, longer, more strongly hooked bill with pale-based lower mandible, narrower black mask with more white around eye, more prominent barring below. ♂ averages whiter below, lacks brownish tones above. Most juvs and some 1st-yrs tinged brown, others grayer, more like ad; on 1st-s note reduced mask and browner wings than ad. Also cf. Northern Mockingbird. Sounds: Song similar to Loggerhead but typically includes dissimilar notes within repetitions; includes short “police whistles” and other melodious notes recalling Northern Mockingbird; also harsh Gray Catbird-like notes. Calls include an incessant nasal nya-ny-nya. Status: Uncommon and solitary, numbers fluctuating during late fall–winter (Oct–Apr) in n. Lower 48; penetrates farther s. in Great Plains during most winters. Regularly winters in subarctic AK and Canada. Also n. Asia. Rose-throated Becard Pachyramphus aglaiae L 16–18cm, Wt 31–33g. Sole representative of the widespread Neotropical family Tityridae; in N America it breeds locally in a few riparian areas in se. AZ; rare in s. TX. Note large head, stocky build with bushy crest, fairly short tail, stout bill. Large, conspicuous globular nest suspended from high branch in cottonwood. 1st-yr ♂ plumage variably intermediate between ad ♂ and ♀, usually with some pink on throat; like ad ♂ by 2nd fall. TX birds average slightly darker, more richly colored overall than AZ birds. Sounds: Common call a whiny descending seeeeuuuuw and a 2-syllable wee-teeeuuu (~0.5 sec), sometimes with a chattered reedy intro; also a sharp pik near nest. Dawn song a long series of couplets, similar to common call. Status: Very local breeder in se. AZ, known from only a few sites. Migration mainly Apr–May, Aug–Sep. Wanders n. from e. Mexico to s. TX (mainly winter, has bred); exceptional elsewhere. Also Mexico and Cen America.

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Loggerhead Shrike

Stocky, with wide black mask, blunt dark bill

ad caches food on thorn or barbwire

with Northern Mockingbird

frequently hovers juv (Apr–Nov)

imm

darker ad

paler ad

generally ad-like, but note retained brownish juv primaries

San Clemente Island, CA

Northern Shrike

N. distribution; narrow mask, whitish eyering, pale-based bill ad ♂

shrikes fly with strong undulations, quick bursts of rapid wingbeats

many have brownish cast in 1st winter

gray imm (Sep–Mar)

1st-w has pale-tipped greater coverts

♀ averages browner, messier mask than ♂

brown imm (Sep–Mar)

ad ♀

Rose-throated Becard

Big head, short, down-cocked tail, dark cap; se. AZ, rarely s. TX

1st-yr ♂

more strongly hooked tip than Loggerhead

ad ♀

pale collar

stout bill

underparts whitish in AZ, buffy in TX

variable rose-pink patch

ad ♀

ad ♂ nest large globular mass suspended from high branch

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TX birds average darker overall

Townsend’s Solitaire Myadestes townsendi L 20.5–22.0cm, Wt 29–39g (CA). Distinctive long-tailed thrush of w. mountains. Breeds in conifer woodland, including open woods near timberline. Winter migrants descend to foothills, canyons, desert washes, farmland, especially with junipers. Perches rather upright, frequently on dead branches; often still and quiet for long periods, and overlooked easily; sallies to snatch berries, flying insects. Shape, plus gray plumage with neat white eyering distinctive; also note whitish outer tail feathers, buff wingstripe. Juv has extensive buff spotting and dark scalloping; note short dark legs vs. longer pinkish legs of juv Catharus thrushes. Sounds: Common call a plaintive, semi-metallic to ringing whistled heeih. Song a rambling, fairly fast-paced warble, from prolonged outpourings to short bursts, repeated; quality may suggest a musical, slightly mechanical House Finch or a thrasher. Status: Fairly common. Migration mainly Mar–early May, Sep–Nov; rare migrant along Pacific Coast. Very rare in the East mainly Oct–Apr. Also Mexico. OLD WORLD FLYCATCHERS: Muscicapidae. Large diverse family, of which 2 species reach North America as breeding birds, returning to the Old World in winter. Numerous other species occur as rare vagrants to North America, mainly on Alaskan islands. Ages and sexes differ in breeding species; sexes similar in some vagrants; males especially may show seasonal variation. Immature birds resemble adults by 1st winter. 2 species regular, 18 vagrant.

Northern Wheatear Oenanthe oenanthe L 15–17cm, Wt 18–29g. Breeds AK, High Arctic Canada; vagrant elsewhere. Attractive terrestrial bird readily identified by large white rump patch, striking in flight. Breeds on open rocky hillsides of windswept tundra; migrants and vagrants in any open habitats, from golf courses to beaches, farm fields. Hops and runs well on ground, standing upright when alert, and perches readily on fenceposts, rocks; flight strong and sweeping, usually low. ♂ br distinctive; ♀, imm, and ♂ nonbr similar (after rapid molt in Aug, before migration), with buffy underparts, variable dark eyestripe (♀) or veiled mask (♂). White rump and tail base set off black T pattern on tail tip. Juv has pale dappling on upperparts, dark scalloping on breast, quickly attains ad appearance. Greenland breeders (ssp leucorhoa) average larger, richer buff below. Sounds: Hard dry chak, often doubled, and high nasal sew. Song a variable, disjointed warble of whistles and scratchy notes, from perch or in steeply climbing flight; sometimes prolonged. Status: Uncommon to fairly common. Arrives mid– late May; departs late Aug–mid-Sep; stragglers into early Oct. Rare fall vagrant in the NE mainly Sep–Oct; exceptional elsewhere and in late spring. Winters in Africa. Also Old World. Bluethroat Luscinia svecica L 15–16cm, Wt 15–25g. Breeds AK. Attractive, mostly terrestrial bird that breeds in tundra willow thickets, usually along streams, and ranges to adjacent rocky tundra. Typically skulking, rarely seen unless singing. Sings from atop shrubs and in jerky, steeply climbing flight; song period notably brief, usually only 2–3 weeks in late May–mid-Jun, after which it becomes much harder to find. Hops on ground under and near cover, tail often cocked. ♂ br stunning and distinctive; ♀, imm, and ♂ nonbr duller, but note bold pale eyebrow, dark mustache or necklace, some blue or orange on throat except dullest imm ♀s. Rusty base to tail sides distinctive, flashed in brief flight view. Juv has pale dappling on upperparts, dark mottling on breast; quickly attains ad appearance. Sounds: Song is striking, a varied, fairly rapid-paced, and often prolonged outpouring of whistles, chips, trills, buzzes, including mimicry, with phrases often repeated up to 20+ times; suggests a lightweight mockingbird or thrasher. Calls include a gruff dry tchak and plaintive whistled heet in alarm, similar to wheatear. Status: Fairly common. Arrives late May–early Jun; departs late Aug–early Sep; stragglers into early Oct. Also Old World.

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Townsend’s Solitaire

Long-tailed gray thrush of w. mountains

brighter ad

juv (Jun–Sep)

duller ad short, grayish legs; cf. Catharus

Northern Wheatear

Mainly w. AK

♂ nonbr (Aug–Feb)

♀ br (Mar–Jul)

bold white rump and black tail band

♀/1st-w (Aug–Feb)

♂ br (Mar–Jul) AK

♂ br

Greenland birds brighter overall

N. AK

Bluethroat

whitish eyebrow

♀ br (Mar–Jul) rusty base blackish necklace 1st-w/nonbr ♂ (Aug–Mar) 1st-w ♀ (Aug–Mar)

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♂ br (Mar–Jul)

CHICKADEES AND TITMICE: Paridae. Small, acrobatic, agile birds with short, strong bills. Forage on insects and seeds, often visit feeders. Nest in tree cavities, birdhouses. Chickadees (Poecile) have boldly patterned heads and black throats; titmice (Baeolophus) have short crests. Ages and sexes similar. Juveniles (mainly May–August) have fleshy gape, loosely textured plumage; quickly attain adult-like plumage. Core species of mixed-species flocks. Diverse complex vocalizations given year-round. Iconic chick-a-dee calls consist of 3–6 distinct types of notes repeated in consistent order. Different numbers of dee notes convey different information (e.g., level of danger, proximity). Far-carrying musical whistled songs (mainly February–June) are lacking in some species. Complex gurgle songs are given year-round. Also give a variety of innate short calls. 12 species.

Black-capped Chickadee Poecile atricapillus L 12–15cm, Wt 9–14g. Hardy, bold and inquisitive chickadee that often approaches closely. Found in a variety of deciduous and mixed forests, riparian woodlands and thickets, and around towns and wooded parks. Long-tailed and large-headed with buffy sides, dark slaty wings, and tail with contrasting whitish edging; note especially, whitish edging to greater coverts. Very similar to Carolina Chickadee, with which it regularly hybridizes in narrow range of overlap. Geographic variation largely clinal, with darkest birds in the Pacific NW, palest in AK and Rockies. Sounds: Common call the familiar chick-a-dee dee dee dee. Flight call a sharp upslurred sik, usually lower-pitched than Carolina. Song a pure whistled 2–3-part fee-bee, or hey, sweetie. Songs more variable in the Pacific NW, sometimes with 5+ notes. Other isolated populations often sing odd songs. Gurgle song a quick descending warble, sometimes repeated. Status: Common resident. Occasionally stages large irruptions to the s., mainly Oct; smaller movements in May. Carolina Chickadee Poecile carolinensis L 10–12cm, Wt 8–12g. Se. counterpart of Black-capped Chickadee and very similar in all respects but somewhat less bold. The only chickadee throughout most of range. Smaller and duller than Black-capped, with smaller head, shorter tail, duller, less contrasting wings and tail, smaller and neater bib, grayish wing coverts; gray wings show weak contrast with back; cheek patch blends to grayish at rear (vs. clean white in Black-capped). Hybrids occur in narrow zone of overlap; most appear intermediate, but some appear like either parent. Note voice, but beware that chickadees learn songs, including the “wrong” song; hybrids sing either species’ songs or intermediate songs. Calls are innate and more helpful. W. birds average grayer with less buff on flanks; much individual variation. Sounds: Chick-a-dee calls tend to be higher, harsher, and more rapid than Black-capped (within similar context); typically 5–9 dees/sec vs. 3–5 in Black-capped. Variable song 3–5 high whistled notes with big changes in pitch, e.g., fee-bee-fee-bay. Other vocalizations similar to Black-capped. Status: Common resident in the SE. Very slowly expanding n. and upslope, replacing Black-capped. Rarely strays; exceptional to Lake Erie. Mountain Chickadee Poecile gambeli L 11–14cm, Wt 10–12g. Common chickadee of w. coniferous forest. Favors drier open habitat, particularly when overlapping with other chickadees during breeding season. Whitish eyebrow distinctive (can be somewhat messy in late summer). Grayish wings lack white edging of Black-capped. Rarely hybridizes with Black-capped or Boreal Chickadee. Hybrids with Black-capped usually have less pronounced eyeline, buffy flanks, and whiter edges to wings. Geographic variation clinal: Pacific (baileyae Group) has gray back and flanks (darkest in s.); Rocky Mts (gambeli Group) has brownish or olive tones to back, buffy or cinnamon flanks. Sounds: Vocalizations similar to Black-capped; chick-a-dee call usually harsher, slower; song more variable, usually with 3+ notes, often little pitch change. Status: Common resident. Irrupts to lowlands infrequently after crash in food resources, mainly fall–winter. Also n. Baja California.

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Black-capped Only chickadee in the SE; drabber Chickadee smaller, than Black-capped

Widespread n. chickadee; contrasty wing markings

juv (May–Aug)

Eastern juv (May–Aug)

grayish secondary edges, plain greater coverts

blackish wings with white-edged secondaries, greater coverts fresh Eastern ad (Sep–Jan)

fresh Eastern ad

Carolina Chickadee

fresh ad (Sep–Jan)

dark tertials contrast with gray back

grayish tertials blend with back

fresh ad

worn Eastern ad (May–Aug)

worn ad (May–Aug) fresh ad

fresh Eastern ad

variable; shows mix of traits

w. populations average grayer

fresh Pacific ad fresh Rockies ad

Carolina × Black-capped hybrid

fresh ad

Mountain Chickadee

Chickadee of w. mountains; white eyebrow juv (May–Aug)

eyebrow often indistinct when worn grayer tones, weaker eyebrow than Rocky Mts

fresh Pacific ad (Sep–Jan)

fresh Rocky Mts ad (Sep–Jan) with Black-capped For general queries, contact info@press.princeton.edu.

worn ad (May–Aug)

Sedge Wren Cistothorus stellaris L 10.0–11.5cm, Wt 7.5–9.5g. Secretive bird of wet grassy meadows, marsh edges, usually with scattered shrubs; also damp weedy fields, saltmarsh in winter. Smaller, buffier, shorter-billed than marsh wrens; note uniformly patterned upperparts, weak eyebrow, usually streaked crown (unstreaked on juv). Sounds: Calls include a rich warbler-like chip (often doubled), more complex buzzy chips, a hard vibrant chrrt, and a liquid chatter; much gradation between call types. Song, given day and night, 2–4 strong chips followed by a staccato rattle; consecutive songs usually similar (varied in marsh wrens); cf. Common Yellowthroat rattle. Status: Locally common in n. Great Plains in summer, Gulf Coast in winter, scarcer eastward; very rare to the Pacific Coast. Migration mainly Apr–May, Sep–Nov. Nomadic movements s. and e. Jul–Sep for 2nd nesting in ephemeral habitats. Winters to ne. Mexico. Western Marsh Wren Cistothorus plesius L 11.5–12.5cm, Wt 9–13g. W. counterpart to Eastern Marsh Wren; similar in habits, the two differ distinctly by song, subtly by appearance. Generally less contrasting head pattern in Western; cheek and neck markings smudgier, less streaked; breast dingier, more grayish; crown and back often paler. Pacific Coast birds average darker, more rufous. Some interbreeding with Eastern in se. SK. Sounds: Calls similar to Eastern Marsh Wren; jit call averages softer, buzzier; churr-type call a much harder chatter. Song harsher, more rattling than Eastern, with 1–3 hard tuk introductory notes (softer introductory notes than Sedge Wren); lacks musical twitter; consecutive songs differ. Subsong more bubbly, closer to Eastern. Status: Locally common. Migration mainly mid-Mar–early May, Sep–Nov; some populations resident. Also to Mexico.

Eastern Marsh Wren Cistothorus palustris L 11.5–12.5cm, Wt 9.2–14.0g. Shy but pugnacious bird of freshwater and saltmarshes, favoring pool or creek margins with taller grasses, particularly cattails, bulrushes, cordgrass. Migrants also in damp weedy fields. Usually hidden but sometimes sings from exposed perch or in fluttering flight low over marsh. Note bold eyebrow, plain dark crown, streaked upper back bordering solid rusty-brown scapulars, whitish breast; cf. Sedge, Carolina Wrens. Very similar to Western Marsh Wren. Overall brightness varies; interior birds average larger, brighter; Worthington’s (griseus; resident on s. Atlantic Coast) distinctively grayish with mottled breast band. Sounds: Highly vocal, both day and night. Calls include a husky jit (more liquid in Worthington’s), often doubled or extended in a series (cf. Ruby-crowned Kinglet); also a variable series of grating churr notes (often mistaken for more musical Black Rail churr) and various other buzzy notes. Song a variable bubbly trill with buzzy introductory note; sometimes accompanied by musical twittering, especially on Atlantic Coast; consecutive songs usually differ. Status: Locally common. Migration mainly mid-Mar–mid-May, mid-Sep–mid-Nov; some populations resident. Winters to cen. Mexico. Carolina Wren Thryothorus ludovicianus L 12.5–14.0cm, Wt 18–23g. Noisy resident of moist woodland, edges, gardens. Often hides in underbrush but will sing in the open; investigates building crevices, visits feeders. Pairs, territories maintained and vociferously defended year-round. Note stocky shape, rufous upperparts, bold eyebrow, variable buffy underparts. Cf. slimmer, longertailed Bewick’s Wren (note range). Juv paler below, scalloped crown and malar. Tamaulipas (berlandieri Group; s. TX and ne. Mexico) averages duller with bolder dark markings than Northern (ludovicianus Group). Sounds: Common calls include a ringing pip or pi-dip and a descending musical trill, like a finger running down comb. Variable harsh scolding notes (~3–6 notes/sec) have rising inflection, cf. more mewing scolds of Northern House Wren. ♀ gives nasal rattle, often overlapping ♂’s song. Song a loud, ringing series of ~3–10 whistled phrases, e.g., tea-kettle tea-kettle tea-kettle; speed variable; cf. smoother, more trilled Kentucky Warbler. Songs in s. TX average lower, simpler. Status: Common, mainly resident; expanding n. but limited by harsh winters. Some fall dispersal n. and w. of mapped range; exceptional to MT, AZ. Also to n. Cen America. 424

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Sedge Wren

Small and buffy, streaked back and crown, weak head pattern flight low and weak

streaked throughout rich buff

fresh ad (Sep–May)

worn ad (May–Sep)

W. marshes; bold eyebrow, Western Marsh Wren E. marshes; bold eyebrow, Eastern Marsh Wren dark crown, dark crown, streaked more distinct cheek dingier breast, smudgier streaked back; back; bubbly song and neck streaking head markings than rattling song than Western Eastern brighter ad

Pacific Coast ad

brighter ad

clean white to pale buff

juv (May–Sep) Western juv similar

often no blackish on cap

duller ad

duller ad Worthington’s ad

Carolina Wren

Stocky; rufous upperparts, bold eyebrow averages duller, more heavily barred than Northern

juv (Apr–Sep)

Tamaulipas ad paler Northern ad brighter Northern ad

underparts sometimes pale

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Setophaga virens superspecies. Four closely related warbler species (including Golden-cheeked); all have yellow face, black throat, bold white wing and tail markings, and buzzy songs. Where ranges overlap, Townsend’s Warbler regularly hybridizes with Hermit and Black-throated Green Warblers, causing ID challenges. These hybrids are highly variable; some are recognizable by intermediate characteristics, others not distinguishable in the field from parent species. Black-throated Gray Warbler is a more distant relative sometimes considered part of this group.

Black-throated Green Warbler Setophaga virens L 11.5–12.5cm, Wt 8.0–9.4g. Breeds in various forest types, usually with conifers, especially hemlock, spruce; also cedar and cypress swamps on s. Atlantic Coast. Note yellow face, pale green cheek patch, mostly white underparts with streaked sides, plain green back, pale yellow wash on breast and rear flanks; cf. ♀ Townsend’s and Golden-cheeked Warblers. Ad ♂ has solid black throat, veiled with pale tips in fall; 1st-w ♀ averages weakest flank streaking, cleanest white throat; ad ♀ and 1st-w ♂ intermediate and variable. S. Atlantic Coast breeders (“Wayne’s”) not field identifiable; arrive earlier in spring (late Mar). Sounds: Chip a hard tik; harder, higher than Yellow-rumped Warbler (Myrtle). Flight call a thin, rising, pure-toned seet (similar to Orange-crowned Warbler, higher than Myrtle). Song a simple buzzy series; Type A, ZEE ZEE ZEE zoo ZEE; Type B, zoo ZEE zoo zoo ZEE; little variation. Status: Common. Trans-Gulf migrant, most numerous through Appalachians and the Midwest. Migration peaks mid-Apr–early May, late Sep–Oct (Gulf Coast); early–mid May, Sep–early Oct (Midwest). Rare in most of the West. Winters mainly Mexico and Cen America; less commonly Caribbean, FL, TX. Townsend’s Warbler Setophaga townsendi L 11.5–12.5cm, Wt 8.1–9.6g. Breeds in Pacific NW spruce-fir forest, particularly old growth, where ♂s sing from treetops. All plumages show strong cheek patch, bright yellow face and breast. ID complicated by regular hybrids with Hermit and occasionally Blackthroated Green Warblers. Cf. ♀ Blackburnian Warbler. Ad ♂ has solid black crown, cheeks, and throat, veiled with pale tips in fall. Ad ♀ and 1st-w birds similar; 1st-w ♀ averages palest overall with weakest flank streaking, cleanest throat, thickest shaft streaks on wing coverts; 1st-w ♂ averages broader black markings than ad ♀. Sounds: Chip and flight call very similar to Black-throated Green. Song a highly variable series of buzzy and shrill notes; typically grows in pitch and volume, ends emphatically. Very similar to Hermit. Black-throated Gray Warbler lower, rougher, more slurred, lacks shrill elements, typically has 2-syllable (vs. 1-syllable) intro phrases. Some songs recall Black-throated Green. Status: Common. Migration mainly late Mar–May, Aug–Oct; shifts w. in spring, e. in fall. Rare in the East mainly Oct–May. Winters to Cen. America. Hermit Warbler Setophaga occidentalis L 12–13cm, Wt 9.2–11.0g. This close relative of Townsend’s Warbler breeds farther s. in mature fir and pine forest and prefers sparser understory. Note plain underparts, yellow restricted to head, beady dark eyes on plain face, grayish back. Drab birds show complete yellow eyering, weak cheek patch. ID complicated by regular hybrids with Townsend’s. Cf. Olive Warbler. Ad ♂ has solid black throat, veiled with pale tips in fall; 1st-w ♀ drabbest, lacks black on throat, has thickest shaft streaks on wing coverts; 1st-w ♂ similar to ad ♀ but with dark back streaks. Sounds: Chip and flight call very similar to Townsend’s. Song very similar to Townsend’s, sometimes inseparable; averages thinner, more piercing, with typically 2-syllable (vs. typically 1-syllable) intro phrases; lacks longer slurred elements commonly present in Townsend’s. Status: Locally common. Migration mainly Apr–May (primarily along W Coast), late Jul–early Oct (primarily through Sierra Nevada). Rare e. of mapped range mainly spring. Winters Mexico, Cen America; sparingly CA.

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Townsend’s × Blackthroated Green Warbler hybrids Highly variable; often combine black head/throat pattern of one parent with yellow of the other

Yellow face, pale greenish cheeks, yellow wash on rear flanks

Black-throated Green Warbler 1st-w ♂ similar

1st-w ♀ (Jul–Apr)

ad ♀

ad ♂

♀

ad ♂

hint of yellow

Townsend’s × Hermit Warbler hybrids

Yellow face and breast, bold dark cheek patch, green back

Highly variable; often combine Hermit-like face pattern with greenish back, flank streaking, yellow breast

Townsend’s Warbler 1st-w ♂ similar

1st-w ♀ (Jul–Mar)

ad ♀

ad ♂

♀

ad ♂

often a few streaks ad ♂

complete yellow eyering

dull grayish brown

1st-w ♀ (Jul–Mar) ad ♀

1st-w ♂ (Aug–Mar)

Hermit Warbler

Beady eyes on plain yellow face, faint/no cheek patch, plain underparts, grayish back

ad ♀

yellow face, plain underparts

olive wash when fresh

♀

sometimes a few fine streaks

1st-w ♂ (Aug–Mar) ad ♂

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variable black

Pine Warbler Setophaga pinus L 12–13cm, Wt 9.5–13.7g. Rather sluggish, hardy, long-tailed warbler; winters farther n., returns earlier in spring than similar species. Strongly associated with pines, particularly mature pine forest with dense canopy, sparse understory; also isolated groves of tall pines. In winter, often with bluebirds, Chipping Sparrows in open fields; visits feeders. Cf. fall Blackpoll and Bay-breasted Warblers; note Pine’s longer tail, bigger head and bill, duller wing pattern (lacks crisp white primary tips), darker cheeks, plain back. Cf. Yellow-throated Vireo. Difficult to age or sex in fall–winter: ad ♂ brightest overall, most extensive yellow below; 1st-yr ♀ dullest, often lacks yellow; ad ♀ and 1st-w ♂ intermediate (♂s average brighter overall with yellower eyering, but some overlap). Sounds: Chip similar to American Redstart. Flight call a high soft sew, less descending than Northern Parula. Song a musical trill, typically fading in at beginning; speed variable. Cf. usually longer, more mechanical Chipping Sparrow; more ringing, even-volume Dark-eyed Junco. Status: Common. Migration mainly Mar–Apr, Sep–Oct. Rare in the West, mainly late fall–winter. Also breeds Caribbean.

Blackpoll Warbler Setophaga striata L 12–13cm, Wt 10.8–12.9g. A champion migrant among warblers, may fly 3+ days (3000+km) nonstop over Atlantic Ocean in fall. Breeds in stunted spruce forest near treeline, riparian spruce-alder-willow thickets at tundra margins. Spring migrants often in tall flowering trees, where frequently detected by distinctive insect-like song. Sturdy and long-winged; bobs short tail shallowly. Nonbr similar to Bay-breasted Warbler: note yellow-orange feet (sometimes dull), variable lemon-yellow wash to face and breast, clean white undertail coverts, breast/flank streaking (can be faint), thinner bill with gray to yellowish base; greater coverts average narrower white tips, broader grayish edging. Cf. Pine Warbler. Aging and sexing seldom possible in fall–winter: streaking averages heaviest in ad ♂, weakest in 1st-yr ♀; ad ♂ often shows dark lateral throat stripes. Sounds: Chip similar to American Redstart but more hollow/ringing. Flight call like Yellow Warbler. Song a very high series of insect-like notes, loudest in middle; speed highly variable (sometimes trilled); songs average more staccato in the West, more slurred in the East. Status: Common. Elliptical migration route through the SE/e. Gulf (uncommon to TX) in spring, the NE (uncommon s. of NC) in fall. Migration peaks mid-Apr–early May (Gulf Coast); mid–late May and Sep–Oct (Great Lakes and the NE); lingers well into Nov on the Atlantic Coast. Scarce in much of the West but regular through the Great Plains in May, Pacific Coast in Sep–Oct. Winters n. S America. Bay-breasted Warbler Setophaga castanea L 12–13cm, Wt 11.0–12.5g. Beautiful, soft-singing boreal specialist; breeds mainly in mature sprucefir forest, often near water. Migrants use diverse habitats but often seek out ornamental spruces in spring. Nonbr birds very similar to Blackpoll Warbler in appearance, habits; note grayish feet, lime-green head (brightest on nape), variably buff-toned flanks and undertail coverts, faint/no breast streaks (confined to breast sides if present), heavier bill with gray to pinkish base; greater coverts average broader white tips, thinner pale edging. Cf. Pine Warbler. Difficult to age or sex in fall–winter: ad ♂ brightest, with rich chestnut flanks, strongest back streaks, slate-gray uppertail coverts with thick black centers; 1st-w ♀ dullest, with faint buff wash on flanks, faint back streaking, plain olive-gray uppertail coverts; ad ♀ and 1st-w ♂ intermediate. Sounds: Chip similar to American Redstart; softer than Blackpoll. Flight call similar to Blackpoll. Song a short (~1 sec), soft, up-down series of very high, thin slurred whistles, fading in slightly; downslurs longer than up; pattern often uneven. Cf. longer song of Black-and-white Warbler; more staccato Cape May Warbler; louder, simpler, more emphatic American Redstart. Status: Uncommon to fairly common; populations higher during spruce budworm outbreaks. Trans-Gulf migrant, most numerous through the Midwest, less so e. of Appalachians. Migration peaks late Apr–early May, late Sep–Oct (Gulf Coast); mid-May, Sep (Midwest and NE). Rare in the West. Winters s. Cen America, n. S America.

460

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Pine Warbler

Relatively large and long-tailed; darkish cheeks; usually in pines

bold broken eyering ad ♀

rounded patch dull wing pattern; cf. Blackpoll, Bay-breasted

buff brown to grayish overall

dull 1st-yr ♀

♀ nonbr/ 1st-w ♂

long with prominent notch

♀

variable buff wash in fall

(Aug–Mar)

ad ♂ juv (Apr–Sep)

flocks with bluebirds in winter

Blackpoll Warbler

Stocky, long-winged, short-tailed; yellow-orange feet white tips bolder than Bay-breasted

usually some blurry streaks

clean white

♀ br (Mar–Aug)

dull nonbr (Aug–Mar)

♀

variable yellow wash on face and breast

♂ nonbr (Aug–Mar)

bright nonbr (Aug–Mar)

some birds much yellower; cf. Pine Warbler

Proportions similar to Blackpoll; grayish feet, variably buff-toned flanks buffy patch

lime-green head, brightest on nape brighter birds similar to 1st-s ♂ dull nonbr (Aug–Mar) white tips bolder than Blackpoll

♂ br (Mar–Aug)

Bay-breasted Warbler

♀ br (Mar–Aug)

drab with no streaks

♀

drab ♀ br (Mar–Aug)

some 1st-s ♀s very drab; note bold wingbars, buff flanks

♂ nonbr For general queries, contact info@press.princeton.edu.

♂ br (Mar–Aug)

Snow Bunting Plectrophenax nivalis L 14–15cm, Wt 30–40g. A sign of winter across the US-Canada border region, Snow Bunting favors open farmland, sparse fields, beaches. Feeds by shuﬄing nervously on the ground, flashing bold white wing patches when flushed. Large flocks occur in open country, undulating low across the landscape, appearing tan and white; often with Horned Larks and Lapland Longspurs. Breeds in cavities on rocky tundra, outpost towns. Confused with Horned Lark (in flight) and range-restricted McKay’s Bunting (which see). Stunning breeding plumage attained through wear. ♂ br overall whiter and blacker-backed than ♀ br. In nonbr plumage, ages and sexes similar when perched, but in flight note ♂’s extensively white wings, ♀’s reduced white wing patches. 1st-yr averages darker than ad of respective sex, but much variation; 1st-yr ♀ averages smallest white wing patches. Worn brown juv primaries noticeable in 1st-yrs, especially when with blacker-winged ads; differences most prominent in 1st-s imms. Sooty juv plumage held only briefly; rapidly attains tan/ rusty feather tips of nonbr plumage in Aug–Sep, prior to migration. Sounds: Song a variable series of jumbled whistles and burry notes often given in flight display; lower and slower than Lapland Longspur. Subsong, sometimes heard in late winter, a rambling series of squeaky and burry notes. Typical calls given by winter flocks on the ground and in flight include a longspur-like rattle (softer, more musical than Lapland); a soft, pure-toned, downslurred whistled teeeu; also a harsh Dickcissel-like brrrt. Status: Fairly common, but local and nomadic in winter. Migration mainly Mar–Apr, Oct–Dec. Rare to very rare s. along W Coast. Also Eurasia.

Snow Bunting flock in winter

McKay’s Bunting Plectrophenax hyperboreus L 14–15cm, Wt 30–40g. Restricted to AK, this whiter counterpart to Snow is a hard bird to see without targeted effort. Considered a ssp of Snow Bunting by some authorities; extreme individual variation in both taxa makes ID of some intermediate individuals and presumed hybrids impossible. Whiter than Snow in all corresponding ages/ plumages. Ad ♂ usually straightforward: note white back, occasionally with fine dark streaks, smaller black wingtips, less black in alula and tail than Snow. Ad ♀ can be more confusing, and differentiation of ad ♀ McKay’s and 1st-yr ♂ Snow particularly tricky, requiring details of spread wings to determine ID. Note subtle differences in black pattern in primary coverts: more extensive dark at bases on ♀ McKay’s vs. just black at tips in ♂ Snow. Also note more solid black wingtip of ♂ Snow vs. pale veins of white extending into the dark wingtip in ♀ McKay’s. Dark extreme ♀ McKay’s similar to palest examples of ♀ Snow; note wing-pattern differences, whiter rump, tail in McKay’s. Juv McKay’s averages buﬃer above and whiter below than Snow. Sounds: Song and calls indistinguishable from Snow. Status: Common but extremely local, breeding only on St. Matthew and Hall Islands, AK, in the Bering Sea. Migration mainly Apr–May, Oct–Nov. Winters coastal w. AK. Regular transient on Pribilofs and St. Lawrence Island, AK. Very rare vagrant on W Coast s. to Pacific NW. Brambling Fringilla montifringilla L 13.5–16.0cm, Wt 17–30g. Striking Eurasian finch; regular in w. AK. A member of the small subfamily Fringillinae (of the Fringillidae, p. 524), it lacks a crop, feeds its young insects, and eats seeds year-round. In native range, found in open woods, brush and fields, hedgerows, coastal marsh; in AK mainly on tundra; winter vagrants visit feeders. In all plumages, note orangy breast and shoulders, white rump. All nonbr plumages similar; ad ♂ averages brightest with most black; 1st-w ♀ averages palest, weakest flank spotting. Sounds: Calls include a soft nasal chut and a snarling upslurred zree (cf. House Finch). Status: Primarily Eurasian. Rare but regular migrant in Bering Sea region, AK, mainly late May, Sep–early Oct, but records nearly year-round. Rare vagrant to Lower 48 in winter. 484

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Bold white wing patches in all plumages

♂ nonbr

juv (Jul–Sep)

Snow Bunting

♀ washed

black back veiled white

dusky

(Sep–Apr)

blackish

♂ br (Apr–Aug) ♀ has dark

ages similar

primary coverts

♀ br (Apr–Aug) with Horned Lark and Lapland Longspur

1st-w has tapered tailfeather tips, duller wingtips

♀ nonbr (Sep–Apr) all -dark 1st-w often dark

1st-w ♀

Restricted to w. AK 1st-w ♀

black restricted to tips extensive black

ad often paler

extensive dark

♂ nonbr

1st-w ♂

♀ nonbr ♀ nonbr

reduced or no black

usually all white

McKay’s Bunting

whiter than Snow less black than Snow

1st-w ♂ dark bases and tips

usually all white

dark reaches coverts

dark/light pattern

♂ nonbr

♂ nonbr (Sep–Apr)

juv (Jul–Sep)

♀ nonbr

back whiter than Snow

limited black

♀ br

(Sep–Apr)

♂ br (Apr–Aug)

(Apr–Aug)

Brambling

AK only; orange breast and shoulders, white rump

♂ nonbr

♀ nonbr

1st-w ♀ (Aug–May)

1st-w ♂ (Sep–Apr)

1st-w ♂ For general queries, contact info@press.princeton.edu.

♂ br (Apr–Aug)

White-throated Sparrow Zonotrichia albicollis L 15–17cm, Wt 19–35g. Familiar chunky sparrow; winters in dense habitats from damp woodland edge to suburban hedgerows, often in large flocks. Breeds in mixed and coniferous woods with thick understory (e.g., bogs, overgrown clearcuts, treefalls). Note white throat contrasting with gray breast, bold crown stripes, yellowish supraloral, rusty wings. 2 morphs unrelated to sex or age: “white-striped,” with black and white head stripes, gray cheeks; “tan-striped,” with brown and tan head stripes, brownish-gray cheeks, often some flank streaks. Each usually pairs with the other morph; tan-striped birds do most of caring for young. Rarely hybridizes with Dark-eyed Junco. Sounds: Song a variable series of pure whistles with slight quavering quality, typically 1–2 long whistles followed by 3–4 shorter notes, Oh sweet Canada-Canada-Canada. Call a loud, sharp metallic pink and variable pew-pew-pew-pew-pew during interactions. Flight call a high, even, long seeeet; longer, more level, more sibilant than Song or Fox Sparrows. Status: Common in the East; uncommon to rare in the West mainly Oct–Apr. Migration mainly Apr–May, late Sep–Nov. Winters to n. Mexico. White-crowned Sparrow Zonotrichia leucophrys L 14–17cm, Wt 21–38g. Large, long-tailed conspicuous sparrow of suburban thickets, shrubby hedgerows in open country. Nests in clumps of stunted trees or shrubs in tundra, coastal scrub, and chaparral. 4 groups differ in back/flank color, bill color, head pattern, and voice. 2 Pacific breeding ssp, collectively referred to as “Yellow-billed,” most distinctive, with yellowish bill, drabber brown back and sides, duller head stripes, sometimes a throat stripe (rare in others), and shortest wingtips: s. of Cape Mendocino, CA, Nuttall’s (nuttalli) is resident along the immediate coast in rank thickets; n. of there, pugetensis (affectionately called “Pugies” by birders) is partly migratory, nesting both along the coast and slightly farther inland. Any yellow-billed bird away from the immediate coast during migration and winter should be pugetensis. In the w. taiga, Gambel’s (gambelli) has orange-yellow bill, pale supraloral. In the e. taiga, ssp leucophrys has pinkish bill, dark supraloral, imms with darker brown forehead. The 2 taiga breeding ssp intergrade broadly in the Hudson Bay area. Breeders in mountains of the Interior West (oriantha) appear very similar to leucophrys but usually have darker raspberry-red bill, grayer flanks (also note call). Juv, similar across range, is streaked below, has brown and buff head. Imm like ad but with brownish head stripes; head appears like ad in most by Apr, but retains brown feathers through 1st year in resident Nuttall’s of coastal cen. CA. Ad appears similar year-round. Sounds: Song varies regionally; usually starts with a clear whistle, then a series of musical trills and buzzes. All taiga breeders least variable: I want some Cheez Whiz now. Pacific Coast songs more variable but clearer, with faster phrases, shorter buzzes, e.g., don’t feed Jimmy no cheese; many local dialects. Interior West songs intermediate; much local variation. Call a sharp pink, lower and less metallic than White-throated Sparrow; taiga breeders high and sharp; Pacific flatter; Interior West very sharp, suggesting Blue Grosbeak. Flight call an upslurred vseet; cf. Vesper Sparrow. Status: Common in the West; fairly common in the Midwest and Great Plains; uncommon e. of the Appalachians. Migration timing varies by region: earliest in spring in Pacific states (late Mar–early May), late for a sparrow elsewhere (midApr–early Jun); fall migration begins in late Aug–Sep in the West, generally not until late Sep in the East, and continues through Nov throughout. Winters to cen. Mexico.

Golden-crowned Sparrow Zonotrichia atricapilla L 15–18cm, Wt 21–36g. Large, handsome sparrow breeding in shrubby thickets of the far nw. reaches of the continent and wintering mainly near the Pacific Coast, where it favors dense woody thickets, often in higher-elevation montane chaparral than Whitecrowned Sparrow. Winter ad variable, usually showing hint of br head pattern, often diffusely veiled gray and brown; duller examples and imms suggest imm White-crowned, but Golden-crowneds dingier overall with messier face pattern, faint eyeline, and grayish bill—all ages typically have some yellow on forecrown (absent in White-crowned). Imm head pattern highly variable, some with only a hint of black or yellow on crown; acquire ad-like head pattern by Mar–Apr. Sounds: Song usually a series of 3 (sometimes 4) pure whistles, each on different pitch, the 1st highest, ooh dear me; 1 or more notes usually slurred; some dialects end in a trill. Call a loud, hard flat tsink, cf. California Towhee. Flight call a high, short upslurred, tsuit, much like Chipping Sparrow, lower than Fox Sparrow. Status: Common. Rare in the Interior West, Great Plains, and Great Lakes (mainly winter); very rare in the East. Winters to n. Baja California. 498

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White-throated Sparrow

Stocky, with contrasting white throat, reddish-brown wings with Swamp Sparrow

tan-striped usually has dark throat stripes

tan-striped br

often streaked (more in tan-striped)

some 1st-w very drab with extensive streaks (others ad-like)

1st-w (Oct–Mar)

juv (Jun–Aug) white-striped nonbr (Oct–Mar)

Bold crown stripes, colorful bill

white-striped br (Apr–Jul)

White-crowned Sparrow

lores whitish; yellow-orange bill

streaks more rufous than other ssp

darker crown stripes

1st-w

1st-w leucophrys Gambel’s

juv (Jun–Sep)

ad ad duller white stripes

similar across range

yellow bill

Yellow-billed

blackest streaks

pink bill; warm brown flanks

very similar to leucophrys; averages darker bill, grayer flanks

1st-w

1st-w ad

short wings

oriantha ad

Large, dull gray-brown, always some yellow on crown gray bill

dull 1st-w

typical ad nonbr (Sep–Mar)

white rear crown

Golden-crowned Sparrow black and yellow crown

plain face with faint eyeline

juv (Jun–Aug)

grayish face

br (Apr–Jul) typical 1st-w For general queries, contact info@press.princeton.edu.

Peucaea SPARROWS. Four North American species of larger sparrows with long, rounded tails. Generally solitary and secretive; don’t flock with other species. Three species are similar and diﬃcult to find when not singing. Rufous-winged Sparrow is distinctive.

Cassin’s Sparrow Peucaea cassinii L 13–15cm, Wt 16–22g. Fairly common but inconspicuous breeder of sw. grasslands with scattered yucca, cactus, mesquite. Presence often revealed by skylarking display as bird flies into air and parachutes down, singing. During nonbreeding season also found in pure grasslands, weedy fields, deserts. Flushes very close, then flies low and direct, dives for cover while fanning tail; usually dives into grass, then runs to hide. Cf. Botteri’s Sparrow. Grasshopper Sparrow has shorter tail. Brewer’s Sparrow slim with notched tail. No geographic variation, but some brighter, more rufous, particularly on upperparts, wings, uppertail coverts, and wings. Juv upperparts buﬃer, breast streaked and spotted. Sounds: Song, often given in flight, a haunting whistled trill ending with 2 short lower phrases. Complex song a twittering series of chips and trills. Calls include high thin psit, very similar to Botteri’s; also a quiet twitter. Status: Locally common, but abundance decreases during drought, and range expands greatly in response to moisture, particularly in w. and n. portions of range. Migration mainly Apr–May (but arrival to breeding grounds as late as Jul, depending on moisture), Aug– Oct. Nomadic; sometimes occurs well outside range mainly May, Oct–Nov. Also n. Mexico. Botteri’s Sparrow Peucaea botteri L 13–16cm, Wt 16–25g. Uncommon and local sparrow of desert grassland and coastal prairie with scattered low trees and shrubs. Flushes and flies much like Cassin’s Sparrow, but more often flies to base of shrub and often holds tail closed when diving into cover. From Cassin’s by longer bill with more curved culmen, broad streaks on upperparts (vs. scalloping), unstreaked underparts, darker cap, and plainer throat. 2 distinct populations. SW breeders in semidesert grassland; rustier above, buffy sides. TX breeders in coastal prairie with scattered mesquite and shrubs; darker above, grayer below. Juv has buffy-yellow face and underparts, streaked sides and breast. Sounds: Usually gives song from tall prominent perch, a variable series of 1–2-note phrases followed by a series of notes accelerating into a trill. Flight song rare. Complex song suggests introductory part of song but given slowly over long periods. Calls include a hard sharp psit and twitters. Status: Uncommon and local. TX population declining; now rare and local. Mostly detected late Apr–Sep, but at least some present locally year-round in AZ; very rarely found in winter in TX. Rarely detected in migration; presumably migrates mainly Apr–May, Aug–Oct. Also Mexico, Cen America. Bachman’s Sparrow Peucaea aestivalis L 12–15cm, Wt 19–22g. Elusive except when singing, this sparrow of the SE favors open pinewood with dense understory of grasses, shrubs, and palmetto; also clearcuts, powerline cuts, and old fields with similar rank vegetation along woodland margins. Often sings from same perch for long periods. Forages on ground and flushes from grass only when approached closely. Usually flies short distances; flight bouncy with tail usually pumped. Similar to Cassin’s and Botteri’s Sparrows but typically doesn’t overlap in range or habitat. Grasshopper Sparrow smaller with short spiky tail. E. birds usually darker and drabber, darkest in FL. W. birds more rufous, bright buff below. Juv streaked below, has wingbar. Sounds: Song consists of 2 parts: a thin whistle followed by a musical trill of a different pitch, vaguely suggesting an Eastern Towhee; trill can recall Pine Warbler. Subsequent songs usually differ in pitch and trill. Call a high sharp tsew. Also a metallic chatter when agitated. Status: Mainly resident. N. birds migratory, mainly found Apr–Aug, but secretive nature makes detection diﬃcult in winter throughout range. Populations increased with clearing of forest in early 1900s; range contracting, and now declining across most of range.

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Cassin’s Sparrow

Pale eyering, fine breast/flank streaking, small bill

cf. Grasshopper Sparrow

neat scalloping when fresh broad white corners

pale throat with dark border

pale eyering fresh (Oct–Jan)

juv (Jul–Sep)

worn (May–Jul)

ladder-barred

Botteri’s Sparrow

Souteast AZ and s. TX; no eyering, curved bill, plain below

broad dark streaks

1st-yr retains streaked flanks into Nov

juv (Jul–Sep)

plain flanks

plain wings

fresh SW (Oct–Jan)

worn SW (May–Jul)

fresh TX (Oct–Jan)

Bachman’s Sparrow

Open pinewoods of the SE; rufous back stripes bright rufous and gray

juv (Jul–Sep)

w. ad (Oct–Jan)

e. ad (Oct–Jan)

pale belly

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e. ad (May–Jul)

FINCHES: Fringillidae. Diverse group of small to medium-size gregarious songbirds, most with conical bills, longish wings, undulating flight, often red or yellow plumage tones in males; often seen at feeders. Most are plant specialists, with seeds, fruit, buds, etc., making up most of their diet; insects, spiders also important summer foods for several species. Many species forage for grit, salt along roadsides. Because of their specialized diets, finches often wander in search of food, and northern species periodically engage in large fall irruptions when preferred winter foods are scarce, sometimes appearing 100s of kilometers from core winter ranges. Most species are short- to medium-distance, mainly diurnal migrants, usually in flocks. Ages and sexes usually differ; juveniles often female-like, attain adult appearance in 1st year. Only American Goldfinch has distinct breeding and nonbreeding plumages. Songs vary from a simple series to elaborate warbles, sometimes including mimicry. Flight calls important for identification and critical to separating “types” within the Red Crossbill and Evening Grosbeak complexes (but note that these calls are learned, and Redpolls, for example, may match calls of flockmates; more study needed). Bill size and shape, adapted to preferred food sources, also important for identification. Cf. New World sparrows (shorter wings). 16 species regular (possibly numerous additional cryptic species), 10 vagrant.

Evening Grosbeak Hesperiphona vespertina L 16.5–22.0cm, Wt 55–65g. Handsome, robust finch; breeds in boreal or high-elevation conifers, mixed forest. Occurs in more diverse habitats at other seasons, including suburban tray feeders; eats tree seeds, fruit, buds, sunflower seeds. In boreal regions, breeding productivity highest during outbreaks of spruce budworm, a preferred summer food. Note large head, short tail, massive pale bill, bold wing pattern. Juv has dusky bill, drab head, wing and tail patterns similar to ad; like ad by mid-fall; 1st-yr ♂ retains gray-edged tertials. Subtle regional variation in appearance: ♂s darker in the West (especially Pacific NW), palest in AZ/Mexico; bill deepest in the North, shallowest in AZ/Mexico, shortest in the East; ♂ forehead stripe widest in the East. 5 discrete groups based on flight call: core breeding ranges are the Pacific NW to the n. Rocky Mts (Northwestern, type 1, brooksi); Sierra Nevada, CA (Sierra Nevada, type 2, californica); boreal Canada (Eastern, type 3, vespertina); cen. to s. Rocky Mts (Rocky Mts, type 4, warreni); Sierra Madre, Mexico, n. to se. AZ (Mexican, type 5, montana). Multiple types can occur together in migration/winter. Sounds: Calls include a burry breet (similar in all populations) and higher, descending peer, burry in Eastern, clearer in other populations (see spectrograms). Song a protracted series of single or doubled call notes. Status: Locally common but declining. Populations expanded into the NE during ~1880s–1980s, then withdrew. Roughly biennial irruptive migrations, mainly by n. birds (types 1 and 3) in response to poor seed crop; more limited movements by birds in s. mountains. Migration mainly mid-Apr–May, Sep–Oct (West); Apr–May, mid-Oct–Nov (East). Also Mexico. Pine Grosbeak Pinicola enucleator L 20.0–25.5cm, Wt 47–60g. Robin-size n. finch of open spruce-fir forest, often near treeline, lakes. In winter, small flocks visit towns with fruit trees, feeders, where often remarkably tame. Feeds on buds and seeds, particularly spruce, mountain-ash, ornamental crabapples, often clambering quietly. Note long tail, relatively small head, stubby curved bill, white wingbars. Flies with long undulations, slowish (countable) wingbeats. 1st-yr ♂ typically ♀-like for a full year. Complex geographic variation falls into 2 main groups: Boreal (leucura; AK to NL) and Montane (flammula Group; w. mountains). Ad ♂ scapulars and flanks most extensively gray in Rocky Mts; red darkest in Pacific Northwest (coastal AK to BC). Haida Gwaii, BC, smallest, darkest overall; California birds smallest-billed. Sounds: Song a melancholy, descending warble, slower and sweeter than Purple or Cassin’s Finches; Boreal birds slightly higher-pitched. Flight call of Boreal birds a plaintive whistled hew-de-bee (AK to cen. Can) or a descending whistled he-hew-hew (cen. to e. Can); Montane birds give a lower, burry bri-di-bip (cf. harder, less musical Western Tanager). Status: Uncommon. Montane birds mainly elevational migrants. Boreal birds move annually in variable numbers; irrupt about every 5–6 years, particularly when the mountain-ash berry crop is low. Movements mainly Feb–Mar, mid-Oct–mid-Dec. Also Eurasia.

524

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Evening Grosbeak

Large finch with massive bill, short tail, flashy wing pattern Flight calls of the 5 Evening Grosbeak types

12k 10k 8k 6k 4k 2k hms 0.10

0.20

0.30

hms 0.10

type 1

0.20

0.30

hms 0.10

type 2

0.20

0.30

hms 0.10

type 3

0.20

0.30

hms 0.10

type 4

0.20

0.30

type 5 greenish in summer Eastern ad ♂

juv ♂ (Jun–Oct) ad ♀ Northwestern 1st-yr ♂ (Oct–Aug)

ad ♀

pinkish in fall–winter

variable dark on 1st-yr

ad ♂

Mexican ad ♂ Mexican birds have narrowest bill, palest plumage

Sierra Nevada and Rocky Mts birds nearly as dark

Pine Grosbeak

Large and long-tailed; stubby curved bill, white wingbars paler wings with thinner edging than ad juv (Jul–Sep)

Boreal ad ♂

much individual variation; average regional differences shown

ad ♀

1st-yr aged by molt limit Montane ad ♂ some ♀s and 1st-yr ♂s show russet tones For general queries, contact info@press.princeton.edu.

House Finch Haemorhous mexicanus L 14.0–15.5cm, Wt 20.0–22.7g. The default red finch throughout much of N America, this native of the SW has expanded across the West, and was introduced into NY in 1939 and has since spread across much of the East. Occurs in a wide variety of habitats including towns, suburban gardens. Nest hidden in dense vegetation, often around buildings, especially hanging planters. Slimmer, longer-tailed, and shorterwinged than Purple or Cassin’s Finches, with stubbier, curved bill, rounded crown. Also note weak head pattern, thick streaking on flanks, duller underparts without white. Flight weaker with shorter undulations than Purple or Cassin’s. Juv has buffy wingbars, finer streaking than ad ♀; 1st-yr ♂ often like ad by Sep–Oct but some (mainly in the West) remain ♀-like for a full year. ♂s occasionally duller orange-red or yellow, related to diet. Sounds: Flight calls notably varied, including a burry rising vwin, a more whistled see-ip or serp, and a lower nasal zree (cf. higher, shorter House Sparrow). Song a burry warble; higher, slower, burrier than Purple or Cassin’s, often with 1–2 drawn-out burry notes lacking in those species. Status: Common. Largely resident, but distinct seasonal movements in some areas, particularly the NE, mainly late Feb–Apr, late Sep–Nov. Also Mexico.

Purple Finch Haemorhous purpureus L 14–15cm, Wt 21.0–27.5g. More crimson than purple, this handsome finch is generally less common than House Finch. Breeds in moist coniferous or mixed forest, particularly around bogs, lakeshores, parks with tall conifers; also oak woodland in the West. In winter, also found in shrubby edges, swampy woods. Often forages in outer tree branches on buds, berries, blossoms; regular at feeders. Stockier than House with bigger, more angular head, shorter tail with deeper notch, whiter belly; flight stronger with longer, smoother undulations. ♀ and 1st-yr ♂ have bolder head pattern; ad ♂ washed red above, has weaker flank streaks. Cf. Cassin’s Finch. Juv has orange gape, buffy wingbars, weaker head and breast pattern than ad ♀; 1st-yr ♂ is ♀-like for a full year, sometimes with a hint of pink. 2 distinct populations: Western (californicus; cen. BC southward) and Eastern (purpureus; BC eastward). Western averages darker overall, more washed in buffy olive; ad ♂’s red tones duller, warmer; ♀ and 1st-yr ♂ less contrasting overall, undertail coverts often streaked. Sounds: Flight call of Eastern a soft, ringing pip; Western similar but slightly harder, grading into a much flatter, blackbird-like pwit. Also gives a variable melodic repeated vireo-like whistle; averages more slurred in Eastern (cf. Blue-headed Vireo), quicker in Western (cf. Red-eyed Vireo). Song a fast warble, often with mimicry; faster, more whistled than House, lacking high scratchy notes; lower, richer, smoother than Cassin’s. Western song slightly lower, less patterned; Eastern higher, with more distinct pitch and element changes. Status: Fairly common, but declining in the East. Roughly biennial irruptions by Eastern birds in response to poor seed crops, spruce budworm outbreaks. Migration (limited in Western) mainly Apr–May, Sep–Nov. Also n. Baja California. Cassin’s Finch Haemorhous cassinii L 14.5–15.5cm, Wt 24.5–29.0g. Close relative of Purple Finch, replacing it in the Interior West, where it breeds at higher elevations. Found in open coniferous forest from lower ponderosa pine to alpine spruce-fir. Habits similar to Purple, though more social, semicolonial breeder. Slightly longer-winged than Purple with more angular, often crested look to head, slightly longer, spikier bill. All plumages typically show bolder eyering, bolder pale crescent below eye. Ad ♂ shows bright red crown contrasting more with paler pink face and breast; finer streaks on flanks, undertail coverts. ♀ and 1st-yr ♂ more crisply and finely streaked overall (cf. Pine Siskin); malar and eyebrow more streaked. Aging and sexing as with Purple. Sounds: Flight call is a squeaky, clipped ch’lip. Also gives a burry, vireo-like whistle like Purple. Song similar to Purple but slightly higher, scratchier, more varied; lower, faster than House Finch; often with mimicry. Status: Common. Migration mainly Mar–May, Sep–Nov. Also n. Baja California; winters to cen. Mexico.

530

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House Finch

Longish tail, stubby curved bill, weak head pattern, no clean white juv has buffy wingbars

finer streaks than ad

juv (Apr–Oct)

rounded crown, weak head pattern

ad ♀

variable red; brightest on forehead duller

♂

no red on wings

yellow

♂

heavy streaks

brighter

♂

noticeably slimmer, longer-tailed than Purple or Cassin’s with Purple; note tail shape, belly color

Stockier, shorter-tailed, whiter-bellied than House; cf. Cassin’s head pattern often very weak; cf. House

bold eyebrow bold stripe

wings washed red; cf. House

Purple Finch

Eastern

Eastern ad ♂

♀

Western juv (Jun–Oct) Eastern juv (Jun–Oct) clean white darker, less contrasting than Eastern; buffy-olive wash to flanks and back

often some blurry streaks

Western

♀

Western ad ♂

usually streaked

Longer-winged, more finely streaked than Purple; bolder eyering finer, sharper juv has buffy wingbars

streaks overall than Purple

brightest on crown

♀

juv (Jun–Oct)

Cassin’s Finch bright ♂

streaked fine streaks pale pinkish

dull ♂ note differences in wing and tail length, tail notch For general queries, contact info@press.princeton.edu.

ROSY-FINCHES: Leucosticte. Three closely related species (plus 1 vagrant); all nest in rock crevices in barren, rocky Arctic or alpine habitats with cliffs, rockslides, permanent snowfields, or glaciers. Eat seeds and other plant material, insects in summer, often gleaned from melting snow. Often wander many km in search of food, even during the breeding season. Largely allopatric in summer; mixed winter flocks, sometimes in the 100s, regular at feeders, roadsides below treeline when forced down by snowfall. Winter flocks roost communally in caves, buildings, clusters of Cliff Swallow nests. All have long wings, translucent flight feathers, variable pink on belly, rump, and wings; plumage pale-edged when fresh; bills black in summer, yellow in winter. Juveniles (June–September) have uniform head and body, buffy wingbars, no pink. 1st-years sometimes distinguishable by molt limits (particularly in median coverts); average duller than adults. Males brighter than females, with clearer head patterns, brighter and more extensive pink, especially on belly, greater coverts. Voice similar in all species. Most individuals straightforward to identify, but drabber birds can be diﬃcult; focus on head pattern and overall plumage tone. Juveniles differ in overall color, comparable to that of adults, but much variation and overlap; all identifiable by range.

Gray-crowned Rosy-Finch Leucosticte tephrocotis L 14–16cm, Wt 22–26g (mainland); L17–21cm, Wt 42–60g (Aleutians/Pribilofs). Most widespread and variable rosy-finch, found from sea level in w. AK to high mountains in the Interior West. Combination of warm brown body tones and contrasting gray rear crown distinctive. On dullest ♀s, cf. Brown-capped Rosy-Finch, which typically shows less contrasting nape; also cf. colder-toned Black. 4 main populations: Brown-cheeked (tephrocotis Group; breeds interior mountains from AK to MT) has gray rear crown contrasting with brown cheeks; Hepburn’s (littoralis; breeds Pacific mountain ranges) has gray nape and cheek; Aleutian and Kodiak Islands (griseonucha) and Pribilof Islands (umbrina) birds have head pattern like Hepburn’s but darker and are much larger. Sounds: Most common call is a nasal burry jeer (recalls soft Evening Grosbeak); also a rising vree (cf. House Finch), a low buzzy jrrk, and a harder, somewhat musical pew; much variation. Song a persistent series of burry jeer notes. Status: Locally common. Birds of Aleutians and Pribilofs resident; others migratory, moving mainly mid-Mar–mid-May, Oct–Nov. Very rare in n. Great Plains Nov–Mar; exceptional to the East. Brown-capped Rosy-Finch Leucosticte australis L 14.5–15.5cm, Wt 23–33g. The most range-restricted rosy-finch; breeds above treeline in CO, s. WY. Weakest head pattern among the rosy-finches, and ♂s average more extensive pink below than other species. Extent of gray on nape variable but always duller and less contrasting than corresponding age/sex of Gray-crowned or Black RosyFinches. A few ♂ Brown-cappeds may show a head pattern that matches dullest ♀ Gray-crowned; on such birds, note bright pink belly on ♂ Brown-capped, little/no pink on dull ♀ Gray-crowned. Sounds: Like Gray-crowned. Status: Locally common. Seasonal movements limited, both elevational and s. into NM, mainly Nov–Apr; very rare to UT, w. WY. Black Rosy-Finch Leucosticte atrata L 14–16cm, Wt 22–32g. Handsome rosy-finch of alpine regions in the Interior West. Breeds at higher elevations than other rosy-finches and nests primarily around steep cliffs. Distinguished from other rosy-finches by overall colder plumage tones, blackish in ♂, slate gray in ♀; back and breast edged with brownish-gray scalloping in fresh plumage. Some drab ♀ Gray-crowneds can appear very similar to Black but show warmer tones on cheeks. Sounds: Like Gray-crowned Rosy-finch. Status: Locally common. Disperses from breeding areas and to lower elevations mainly mid-Oct–Apr; rare in winter to CA, NE.

536

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Gray-crowned Rosy-Finch

Brown body, contrasting gray rear crown; much regional variation

Aleutians/Pribilofs ♂ br (Apr–Aug)

all juv rosy-finches similar; differ in overall color

long, translucent juv (Jun–Oct)

Hepburn’s ♂ br (Apr–Aug)

drab Brown-cheeked 1st-w ♀ (Aug–Apr)

Hepburn’s 1st-w ♀ (Aug–Apr)

Brown-cheeked ♂ br (Apr–Aug) Brown-cheeked ♀ nonbr (Aug–Apr)

Brown-capped Rosy-Finch

Restricted range; brownish overall with weak head pattern

♂ nonbr variant with gray rear crown

drab 1st-w ♀ (Aug–Apr) 1st-w ♂ (Aug–Apr)

♂ br (Apr–Aug)

♀ nonbr (Aug–Apr)

Black Rosy-Finch

Interior West; cold plumage tones, contrasting rear crown

drab 1st-w ♀

♀ nonbr (Aug–Apr)

1st-w ♂ (Aug–Apr)

♂ br (Apr–Aug)

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Indigo Bunting Passerina cyanea L 12–13cm, Wt 13–18g. Striking songbird of forest edge, overgrown fields, and riparian areas. The ♂’s cheerful song is frequently heard along country roads, even during the heat of the day. ♂ br often appears all dark, but turquoise and blue tones glow in good light. Other plumages mainly brown with variable buffy/cinnamon wingbars, dark lateral throat stripes (sometimes faint), variable blurry breast streaking; cf. Lazuli and Varied Buntings, Blue Grosbeak. Aging and sexing of brown plumages can be diﬃcult: juv has crisper, whiter wingbars than fall ad, averages heaviest breast streaking, usually little/no blue; ad ♂ nonbr has extensive blue in wings, tail, often body; ad ♀ similar to ad ♂ nonbr but averages less blue. Frequently hybridizes with Lazuli in contact zone. Sounds: Song is a bright series of mostly paired ringing notes; slower, sweeter, less metallic than Lazuli. Calls include a hard spit; cf. Northern Cardinal. Flight call is a coarse buzz, longer/lazier than warbler buzz notes. Status: Common. Migration mainly Apr–May, Sep–early Nov; some molt migration in Jul–Aug, particularly in the SW. Rare in much of the West, mainly May–Jul; regular along Pacific Coast mainly Sep–Oct. Winters to n. S America. Lazuli Bunting Passerina amoena L 13–14cm, Wt 14.5–16.2g. W. counterpart of Indigo Bunting and similar in habits. Breeds in brushy areas, riparian corridors, regenerating burns, from sea level to 3000+m. Migrants may gather in weedy areas near water, often with other buntings; readily attracted to feeders. Brilliant turquoise ♂ distinctive, though its color pattern may recall a bluebird. ♀ and nonbr ♂ similar to Indigo but typically show bolder wingbars, unstreaked warm buffy breast (Indigo’s breast duller, always with at least faint blurry streaking). Juv/1st-w birds show fine, sometimes extensive breast streaking at least into Oct and can be particularly diﬃcult to ID; note relatively cold-toned head contrasting with warmer buff breast (sometimes subtle), breast streaks typically finer, often darker than on Indigo; some intermediate birds best left unidentified. Cf. ♀ Blue Grosbeak, which is larger, heavier-billed. Aging and sexing as with Indigo. Frequently hybridizes with Indigo, and many birds in contact zone show intermediate traits. Sounds: Song very similar to Indigo but typically faster, higher, more metallic, and more fluid, with notes less evenly paired (often 3+ repetitions). Other calls like Indigo. Status: Fairly common. Migration mainly Apr–May, mid-Jul–Oct; concentrates at sw. staging/molting areas Aug–Oct. Very rare in the East mainly Oct–May. Also n. Baja California; winters mainly Mexico. Varied Bunting Passerina versicolor L 11.5–12.5cm, Wt 11.5–13.5g. Primarily Mexican species, occurs along the US border in arid brushy canyons, dense desert washes, brushy riparian edge. Frequently in pairs but not flocks. ♂ often looks solid black until light catches brilliant red nape. ♀/imm remarkably plain brown; can look very similar to Indigo Bunting but note smaller, stubbier bill with more curved culmen, lack of throat or breast streaks, very faint/no pale edging to wing coverts or tertials, shorter primary projection, rounder head. Juv shows thin pale wingbars. 1st-yr ♂ brown for a full year (averages richer brown than ♀), sometimes with hints of blue or red. Ad ♂ heavily veiled with brownish edging when fresh. ♂s in AZ and sw. NM average darker and brighter with less extensive red than birds farther e. Sounds: Song is a rapid jumble of burry whistles; similar to Painted Bunting but slightly lower, slower, choppier; often a few repetitions (none in Painted); higher than Blue Grosbeak. Calls include a husky spit, similar to Indigo. Flight call is a relaxed burry note recalling Blue Grosbeak but lower and much more musical. Status: Locally fairly common. Arrives late Apr–May, departs Sep–early Oct. Exceptional to the Pacific and Gulf Coasts, Interior West. Also s. to Guatemala.

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Ad ♂ br unique; ♀ and imm rich brown with blurry breast streaks, weak wingbars

Indigo Bunting

weak wingbars

upperparts brighter than breast

blurry streaks

♂ br (Apr–Sep)

juv (Jul–Sep)

♀ nonbr

♀ br

extent of blue variable

♂ nonbr (Sep–Apr)

1st-s ♂ (Apr–Sep)

Ad ♂ br unique; ♀ and imm brown with warm buffy breast, bold wingbars

♀ worn

usually finer streaks than Indigo

plain grayish

juv (Jul–Oct)

Lazuli × Indigo hybrid ♂ br (Apr–Sep)

Lazuli Bunting

clean buffy, brighter than head

♀ fresh

♂ worn (Apr–Sep)

♂ fresh (Sep–Apr) variable; most have mottled white belly, weak wingbars

Ad ♂ unique; ♀ and imm plain brown with no streaks; curved culmen, short wingtips juv (Jun–Sep)

♀ fresh

1st-yr ♂ similar

Varied Bunting curved

little/no pale edging no streaks

♀ worn

♂ fresh (Sep–Apr) ♂ worn (Apr–Sep) For general queries, contact info@press.princeton.edu.

Scarlet Tanager Piranga olivacea L 16–17cm, Wt 24–38g. Like a crimson flame piercing the green canopy in e. deciduous forest, the ♂ br is among the most distinctive sights of N American avifauna. It is a forest-interior specialist, especially of oaks; avoids forest gaps favored by Summer Tanager. Note plain blackish wings and tail, pale bill. Ad ♂ nonbr is green with glossy black wings; some have variable blackish brow. ♀ from Summer by greenish cast to plumage, darker wings, rounder crown, longer tail with gray (vs. yellowish) underside, smaller bill, paler lores; in flight, note whitish (vs. yellowish) underwing coverts. 1st-yr aged mainly by molt limits (often obvious on ♂). Some fall ♀s have faint wingbars and pale-tipped tertials (cf. Western Tanager). Sounds: Song robin-like but much burrier and lacking caroling rhythm, with 4–6 more closely spaced phrases, longer breaks between songs; cf. Summer, note Scarlet’s slower pace, shorter pauses, usually 1–2 notes/phrase. Call a loud, vibrant chik-burrr; also a flat hard chik. Flight call a plaintive rising whistle, puee (higher, more pure-toned than other tanagers). Status: Common. Trans-Gulf migrant; migration mainly Apr–May, Aug–Oct. Rare vagrant in the West; mainly fall. Winters mainly s. Cen America, nw. S America.

Summer Tanager Piranga rubra L 17–18cm, Wt 28–30g. Stunning rosyred (♂) or mustard-yellow (♀) songbird of open e. deciduous and pine-oak forest, sw. riparian corridors. Specializes on bees and wasps and often found in proximity to hives; sallies and gleans for insects, fruits. Bulkier, with more crested look than Scarlet or Western Tanager; longer tail frequently cocked upward. Older ♀s can become increasingly reddish, confusingly like imm ♂. Imm ♂ variably splotched with red in 1st year. Western breeders average larger and paler (especially neck sides), larger-billed, ♀ yellower overall than Eastern breeders. Sounds: Song robin-like but burrier, with longer breaks between songs; lacks wispy tones. Cf. Scarlet; note Summer’s usually 3–4 notes/phrase, more abrupt pauses, usually faster pace (variable; Western birds average slower); cf. more slurred Rose-breasted and Black-headed Grosbeaks. Call a strong clucking pit-ti-tuk, more staccato, less burry than Western, often extended into a rattle. Flight call a burry rising pyeee. Status: Common. Trans- and circum-Gulf migrant in the East; migration mainly Apr–May, Aug–Oct. Regularly overshoots breeding range, mainly early spring. Rare in the upper Midwest and NE in early winter. Eastern ssp rare but regular fall–winter vagrant to Pacific Coast. Also n. Mexico. Winters to n. S America. Hepatic Tanager Piranga flava L 17–19cm, Wt 38–40g. Uncommon inhabitant of open pine-oak forest at higher elevations in the SW. “Hepatic” refers to ad ♂’s liver-red plumage. Usually in pairs, often with mixed-species flocks. From Scarlet and Summer Tanagers by drabber plumage with grayish back, dark lores, grayish cheeks, gray flanks, dark bill; brightest color on crown and throat. 1st-yr similar to ad ♀. 1st-s ♂ has variable red patches. Sounds: Song a loud, rich choppy series of 1–2-syllable phrases; recalls Black-headed Grosbeak but slower, with longer gaps between notes, lacks clear elements. Typical call a loud chup, recalling Hermit Thrush. Flight call a nasal, rising vree. Status: Fairly common. Migration mainly Apr–May, Aug–Sep; a few winter locally at lower elevations in breeding range; rare in winter in s. coastal CA. Also s. to S America.

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Plain dark wings, relatively small pale bill

Scarlet Tanager

1st-s of both sexes retain worn flight feathers/coverts

♂ nonbr (Aug–Mar)

1st-s

♂

uniform glossy black whitish

1st-fall ♂ has contrasting black coverts

♂ br (Mar–Aug) ad ♀

Summer Tanager

Plain wings, big pale bill; often raises bushy crest, cocks tail

longer tail than Scarlet

ad ♀

yellowish

duller ♀

variable red patches

reddish ad ♀

1st-yr ♂ (Mar–Aug)

ad ♂ washed red wings, tail, coverts

Stocky and drab; gray flanks and cheeks, bright forehead and throat, dark lores and bill ad ♀/imm

Hepatic Tanager

ad ♂

variable red patches 1st-s ♂ (May–Aug)

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Orchard Oriole Icterus spurius L 15–17cm, Wt 20–22g. Slim, chestnutcolored oriole of the East. Favors brushy fields with young trees, hedgerows, suburban areas. Ad ♂ distinctive, but imm and ♀ easily confused with Hooded: note Orchard’s smaller size, shorter tail and bill, more contrasting wing pattern, yellow-green color (never tinged orange), voice. Imm/♀ also can be mistaken for a warbler due to small size and slim build. Sexes differ. 1st-fall sexes similar, ♀ averages dullest; ♂ attains black throat/lores by Nov–Dec. Sounds: Song a rapid disjointed warble; higher, harsher, faster than Baltimore Oriole; quality reminiscent of Indigo Bunting but more jumbled. Calls include a husky chuk (cf. Red-winged Blackbird), often doubled and sometimes combined with descending hew whistle; also a husky chatter when agitated; chuk call sharper and louder than similar calls of Hooded. Flight call a slightly descending nasal yeeer. Status: Common. Migration mainly Apr–May, Jul–Aug (East), Aug–Sep (Midwest). Rare in winter in the SE and the West. Winters Mexico to n. S America.

Hooded Oriole Icterus cucullatus L 18.5–20.0cm, Wt 23–24g. Locally common oriole that favors ornamental palms, suburban yards, and, less frequently, surrounding native woodland. Nests mainly in palms; if you find palms within its range, you’ll likely find this bird. ♂ distinctive, but cf. vagrant Streak-backed Oriole in nonbr plumage; imm/♀ easily confused with Orchard Oriole. Imm and ♀ from imm/♀ Scott’s Oriole by smaller, slimmer build, longer tail, more curved bill, narrower median-covert bar. Sexes differ. 1st-fall sexes similar; ♀ averages dullest; ♂ attains variable black throat Nov–Dec. Plumage variation confusing, with yellow ad ♂s in both w. and e. edges of the range; orange in the middle: Ad ♂s of Western ssp (nelsoni Group) and those of extreme e. TX average yellower overall, but note restricted black forehead on Western; Eastern breeders (cucullatus/sennetti) more orange, ad ♂ has broader black forehead. Sounds: Song a rapid, disjointed jumble of harsh and whistled notes; often dominated by mimicry. Chatter call hard and rattling, often in short sets; cf. wrens, Wrentit. Commonly gives a rising whistled weet or wink (cf. Bobolink), while both perched and in flight; less often, a blackbird-like chuk. Status: Common. Migration mainly Mar–Apr, Jul–Sep. Scarce in winter in the SW, TX; exceptional to the East. Migrant populations winter mainly Mexico. Also s. to n. Cen America. Scott’s Oriole Icterus parisorum L 19–22cm, Wt 31–35g. Striking, chunky oriole of the arid SW, favoring dry rocky hillsides lined with yucca and agave, bordering juniper or oak woodland. Note black and yellow plumage, finetipped long bill, shortish tail, bold white wingbars. Ads distinctive across most of range (cf. Audubon’s Oriole in s. TX). Juv/imm drabber than other orioles, with brightest color on belly. Juv sexes similar, but ♂ attains increasing amount of black on head/breast from Sep through 1st spring. Some 1st-fall ♂s similar to ad ♀ but usually show more extensive black face, and note relatively worn wings on all 1st-w birds. Sounds: Song a relatively low, rich bubbly jumble recalling Western Meadowlark. Calls include a husky chuk, a short whistled quip?, and a short cat-like reaar. Status: Uncommon to fairly common. Migration mainly Mar–Apr, Aug–Sep. Scarce in winter in CA, TX, AZ; exceptional in the East, mainly winter. Also Mexico.

Orchard Oriole 1st-fall (Aug–Nov)

Hooded Oriole 1st-fall (Aug–Nov)

Scott’s Oriole 1st-fall ♀ (Aug–Nov)

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Small, slim, short-tailed, and short-billed

neat wingbars ad ♀

pale bill

juv (Jun–Aug)

Orchard Oriole

1st-yr ♂ (Nov–Sep)

♂ fresh (Aug–Feb)

♂ worn (Feb–Aug) variable chestnut patches by late winter

1st-fall (Aug–Nov)

Hooded Oriole

Larger than Orchard, with longer tail, longer and more curved bill pale bill; cf. Orchard in early fall

ad ♀

Western ♂ worn (Mar–Jul)

juv (Jun–Sep) Western ♂ fresh (Aug–Feb)

1st-yr ♂ (Nov–Sep)

more graduated tail than Orchard

Eastern ♂ worn (Mar–Jul)

1st-fall (Aug–Nov)

Scott’s Oriole

Fairly large, with pointy straight bill, bold white wingbars juv (Jun–Aug)

1st-yr ♀ (Dec–Aug)

pale bill

usually lacks black

♂ fresh (Aug–Feb)

patterned back, worn wings

ad ♀

variable black

1st-yr ♂ (Dec–Aug)

♂ worn (Feb–Aug) 1st-fall ♂ (Sep–Dec)

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