Nature gives to every time and season some be a u t i e s o f i t s o w n . ~ Charles Dic ke n s
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On the Wings of Climate Change Why the White Ibis Started Flocking Here By Devin Griffiths of The Wetlands Institute White Ibis
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ummer at the shore is a time of frenetic activity as travelers from hither and yon journey here to soak up the South Jersey sunshine. Over the last several years, another group of visitors has joined in from afar – but they’re not using the roads. Perhaps you’ve seen them soaring over Seven Mile Beach, foraging within the verdant salt marsh grasses, or bathing in the freshwater pools nestled in the Avalon high dunes – exotic white birds, wings fringed in black, reddish bills strongly downcurved from base to tip in a graceful arc, and eyes that rival Sinatra’s. We’ve been fielding calls and messages about them since early spring, some from people who have lived in the area for decades. Many are simply looking for an ID, while those who know them wonder why they’re here now. In an area renowned for hosting avian oddities from across – and sometimes out of – the country, these are still reasonable questions. White ibis – for that is what they are – are creatures of the Southern coast. Common in wetlands, estuaries, and mangrove swamps from North Carolina to Florida and around the Gulf Coast down through Texas, these long-legged waders were seldom seen this far north, and never in large numbers: Until recently, a single white ibis in Cape May County was an event of some note, drawing in birders from near and far to catch a glimpse of this rarity.
The white ibis rookery in Ocean City.
In 2019, everything began to change. That year, people around the county reported sightings of a dozen white ibis or more at once (on an August evening, we had 14 at the institute). A year later, they nested in New Jersey for the first time in the state’s history. The site – a wellknown rookery for several other wading bird species at the Ocean City Welcome Center (including great egrets, glossy ibis, and both yellow- and black-crowned night herons) – produced four nests, three of which were successful. The ibis
came roaring back in 2021, establishing multiple nests across the rookery, raising at least 43 young, and putting to rest the idea that 2020 was a fluke. This year, the rookery is once again alive with the raucous squawks of white ibis. The birds have taken up residence there in force, establishing more than 70 active nests, but they’ve also expanded beyond the confines of Ocean City, moving south onto Seven Mile Beach. While no one’s found a second rookery yet, the birds have been seen by many around Avalon in
staggering numbers: upwards of 350 birds foraging in the marshes or roosting in the remnants of native Atlantic maritime forests. Seemingly, the ibis are finding a home here. The question is, why now? Range expansion among birds is nothing new. Several species common to the mid-Atlantic or Northeast didn’t start out that way: Cardinals and mockingbirds pushed north around the turn of the 20th century, Carolina wrens and glossy ibis a few decades later, and red-bellied woodpeckers followed in the second half of the century. The most extraordinary example is the humble cattle egret, which arrived in South America from Africa in the late 1800s and advanced steadily northward throughout the 1900s. It established a breeding population in Florida by 1953, and continued up the coast of North America from there. Exploring a new food source, taking advantage of favorably changed conditions, escaping major habitat disruption – all have been put forth as potential explanations, and any one might be behind the white ibis’ northern charge. The biggest difference is the time frame: While the other expansions played out over decades, South Jersey’s white ibis went from occasional rarities to regular breeders in just a few years. Virginia experienced a longer though even more dramatic boom: White ibis exploded from 77 breeding pairs in 2003 to more than 1,700 in 2018. Again, why? continued on page 116
Seven Mile Times
August 2022
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