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FIGURING OUT THE MYSTERY OF MIGRATION The lives of migratory birds are mysterious. Even to ornithologists! Despite decades of research, it is extremely challenging to understand where different populations of birds are moving, says Jeff Buler, PhD, a radar ornithologist at University of Delaware, “since most species take off in the evening, fly through the first part of the night and land at sunrise.” “Migration has always been a black box,” says Buler, whose seven-year study using weather radar let him observe daytime habitat for the first time. Buler used the very lowest beam of the national weather system’s radar to watch birds right when they leave the ground for their nighttime flight. They learned why growing numbers of nighttime migrators, like warblers and sparrows, are not surviving. “Too many stopover sights have dwindled and increasing numbers of birds are disappearing and dying during migration.” When stopovers that they have used year after year are suddenly nonexistent, birds have to use extra energy to find another one. It’s energy that they don’t have. Birds can lose as much as one-quarter to half of their body weight as they make remarkable journeys of six to 24, and up to three nonstop days for the Black Pole Warbler flying over the Atlantic. How do birds find new places to stop? How do they manage to find their destination? Thankfully, one thing hasn’t changed, says Buler. “Birds are born with a map sense. They have inherent navigational cues, and they build a map with their mind.” Some birds use the sun and the stars to navigate. Some also use the sighting of landmarks, rivers and mountains. But, way too many are being completely misled by city lights, Buler’s study revealed. “They see the glow from three miles away. For instance, birds migrating in the middle of the Adirondack Mountains can see the lights of New York City!” Then, they fly lower toward the beams and get trapped in the beams—becoming disoriented and eventually, landing from exhaustion. Buler credits The Audubon Society’s Lights Out Program for digging deep to find out why birds are colliding into buildings. New York City Audubon’s studies date back to 1997, when they worked with a researcher and recruited volunteers to walk and record the location of every dead bird they sighted on a sidewalk. “We were finally able to identify exactly which buildings birds were flying into,” explains Susan Elbin, PhD, director of conservation and science. “We learned how lights on change the behavior of a bird in flight.” Lights and reflective glass are the culprit, causing 90-200,000 birds a year to collide into New York City buildings and fall to their death. From a bird’s eye view, a window looks like a tunnel or, they see their own reflection and try to attack it. Elbin is quick to clarify, “Birds aren’t flying into 85th story windows. They are colliding with windows mostly in the first four stories in both urban and rural areas.” Turning off lights frees birds and cuts building utility expenses. To date, about 100 buildings have signed on with NYC Audubon to turn off lights twice a year and turn off decorative lights at night during migration. WINNING OVER BOTH BIRDS AND HUMANS What’s good for birds is good for humans—and the economy! Whether you’re an ornithologist, farmer, conservationist, bird lover. . . everyone has creative ideas to make room for migrators, says Reynolds. The Yampa Valley Crane Festival is a perfect example. Since 2012, the fourday festival draws nearly 2,500 bird lovers, scientists and tourists from across the globe. As festival co-founder, Nancy reached out to Crops for Cranes farmers to provide prime viewing spots and tours. She has not only given cranes a place to gather and socialize; Nancy gathers CCCC farmers, festival volunteers, speakers and donors for dinner at the Merrill’s ranch. It’s been yet another piece of fulfilling her personal dream at Yampavian Ranch—that she named for the Yampa River running through it and to honor all the ranch avians. “My dream for the ranch has always been both to attract and protect birds and to provide access to birders and researchers to learn more about the birds.” °
[ For more information about The 8th Annual Yampa Valley Crane Festival, August 29–September 1, 2019, visit https://ColoradoCranes.org/2019-festival. ]
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LEGENDARY LIVING
