Photo: Prothonotary Warbler, David Sloas/Audubon Photography Awards
Tom Blackburn
As you read this, more than three billion birds are preparing to migrate into or through the United States. Some species, such as Ospreys, have already returned to their warm-weather homes in Virginia. Others, including the much-loved warblers, will be arriving from mid-April through mid-May as they make their way to their breeding grounds.
Scientists and observers from at least the time of Aristotle have marveled at and posited ideas about bird migration; one 17th-century scientist hypothesized that some birds spent 60 days migrating to the moon. Since then, our understanding of where and how birds move as the seasons change has grown tremendously thanks to developments in bird-banding and careful observation techniques. Through these advancements, we’ve learned that the Arctic Tern migrates 40,000 to 50,000 miles a year to and from the Arctic and Antarctic. Over its 30-year lifetime, this five-ounce bird may fly the equivalent of three round trips to the moon.
Migration is perilous. The survival of migrating birds depends on their ability to find food and safe spaces to rest and recover along their journey. Habitat loss at any point along their migratory path can have a huge impact on the likelihood they will complete their journey. Insecticides can also devastate migrating birds, killing not only the insects they eat but also the birds themselves. Twenty-five years ago, scientists discovered that 20,000 of North America’s 400,000 Swainson’s Hawks had died because of a now-banned pesticide in Brazil.
Governmental and non-profit organizations in the United States are working with their counterparts in Central and South America to help protect birds along their flyways. The U.S. Forest Service, the National Audubon Society, and the American Bird Conservancy are a few of the many organizations that have undertaken efforts to enhance habitat conservation and improvement, nature education, and the monitoring of bird populations across Latin America, the Caribbean, and the rest of the world. The message from these organizations is clear: If we want to save the birds we enjoy here in Northern Virginia, we have to save the planet.
If you’d like to learn more about migrating birds, BirdCast is a great place to start. BirdCast is a consortium of researchers primarily from the Cornell Lab of Ornithology, Colorado State University, and the University of Massachusetts Amherst that uses weather radar to predict suitable conditions for migration and to create real-time maps of actual bird migrations. Watching the BirdCast map light up as huge flocks of birds take flight at night can be mesmerizing. On a good night, like September 21 of last year, BirdCast’s map may show up to 500 million birds in flight. This spring, check out BirdCast’s forecasts and bird flight map, and if you see a good migration night, head out with your binoculars the next morning to see what birds might have flown in.