30 April 2014 On a Wing and a Prayer: Bird Migration Season Posted by: Aimee Delach | Comments Off on On a Wing and a Prayer: Bird Migration Season For some people, spring means tax time; for others it brings thoughts of Easter or Passover. For me, the best thing about spring is that it is time for the spring bird migration, the best time of the year to see certain species. It’s also a time to reflect on what a tremendous accomplishment migration is, and how fraught with peril for too many birds. While some species of birds remain in the same area year-round, most of our songbird species are “neotropical migrants” – meaning that they breed in the U.S. or Canada, but winter in the warmer climes of the Gulf Coast, or even farther into Central and South America. The month of May, when many of the birds return north, is a particularly good time to be a birdwatcher, for a couple of reasons: first, it is an opportunity to see birds that aren’t present most of the year. Certain warbler species, for instance, breed only in New England and Canada, so many Americans only have a fleeting chance at a glimpse of these species. Also, migration routes tend to be concentrated into “flyways,” with certain spots being “hotspots” where birds reliably congregate to eat and rest up for the next leg of the journey. A good outing during migration can thus turn up a lot more birds than during the breeding season, when species and individuals tend to be more dispersed. Blackburnian Warbler, © William H Majoros/Wikimedia This eye-catching critter is territorial by nature, only forming flocks during migration. If you live in the eastern half of the U.S., you might be able to spot one this spring. Osprey, © Ron Holmes/USFWS In its 15 to 20-year lifespan, an osprey may travel more than 160,000 miles in migrations! Painted Bunting, © Robert Burton/USFWS The wildly colorful painted bunting can be spotted in the southern U.S. during spring and summer. Arctic Tern, © Amir Ayalon The arctic tern – a tiny bird that weighs just 4 ounces – clocks in with the longest migration of all: They take a long, looping path from Antarctica to Greenland, for a total of 44,000 miles each year! Scarlet Tanager, © Putneypics/Flickr Like most songbirds, scarlet tanagers migrate at night, which is why collisions with buildings or communication towers can be such a threat during their journey. Spotted Sandpiper, © S. King/NPS Unlike many shorebirds, which migrate in large flocks, spotted sandpipers migrate alone or in small groups. Western Tanager, © Dave Menke/USFWS This colorful bird can be seen as it traveling north into the U.S. and Canada from its wintering grounds in Mexico. White-rumped Sandpiper, © Tim Bowman/USFWS The white-rumped sandpiper has a particularly long journey: From its wintering grounds in South America all the way to its breeding grounds in the Arctic! American Redstart, © Cephas/Wikimedia Migratory American redstarts can be spotted in all states in the U.S. except those on the Pacific coast. American White Pelican, © Tom Koerner The American white pelican spends its winters along the coasts, but breeds on lakes much further inland across the west, making for a long migration for one of the largest birds in North America. Red Knot, © Hans Hillewaert By late May, another long-distance champ will make its stop here in the U.S. Red knots, which have a migration route of more than 9,000 miles, stop over in massive numbers on their way to breeding grounds in the Arctic. Birds that undertake migration face triple-whammy of threats: Not only do they need quality habitats in both their wintering and breeding ranges, but they also need to survive the trip, which can be thousands of miles in length and full of dangers along the way. Collisions with buildings kill several hundred million birds each year, and other structures, like communication towers and wind turbines, can also be deadly. Feral and free-ranging cats may kill even more songbirds than collisions do. And the evidence is mounting that climate change is playing an increasingly important role in bird declines. Sea level rise is damaging coasts and wetlands that are important feeding grounds. Increased droughts and fires are damaging forest and shrubland habitats. And more subtle, but perhaps even more important changes are happening as well, having to do with the timing of important food sources, particularly the emergence of insects. The average songbird may only weigh about half an ounce, and burns a tremendous amount of energy during migration and breeding, making it especially critical that their arrival at stopovers and breeding sites be timed to match food availability. As climate change throws seasons out of whack, some of these critical timings are getting thrown off – a phenomena known as “phenologic mismatch.” Researchers in Europe have found that phenologic mismatches are an increasingly important cause of bird declines. And in the U.S., birds are actually altering their migration timing to match changing weather conditions—a good strategy, but one that puts them at risk of missing out on major insect emergences. Get out there this spring and see some birds. While you’re at it, help them survive their migration by keeping your cat indoors, limiting the use of pesticides and other chemicals in your yard, making windows and glass doors more bird-friendly, and providing backyard habitat like sources of water, cover and food. Aimee Delach, Senior Policy Analyst, Climate Adaptation Aimee Delach, Senior Policy Analyst, Climate Adaptation Aimee develops and analyzes policies to help land managers conserve and protect wildlife from the effects of climate change, including Arctic species and aquatic animals and ecosystems.