Hope your binoculars are polished and your shade tree seedlings are ready to go- it’s International Migratory Bird Day! Yes, ornithologists’ Christmas is finally upon us, and there’s no better reason to get out there and scan the skies or participate in an official event near you. But on the off chance that you found this page by jumbling the letters in your search for IMDB, a brief introduction may be in order.
International Migratory Bird Day (IMBD) began in 1993, making it one of the few holidays that’s younger than the UNdertheC bloggers. It was originally organized by the Smithsonian Migratory Bird Center and the Cornell Laboratory of Ornithology, and is now run by Environment for the Americas. IMBD aims to raise awareness of, you guessed it, migratory birds. Wait a sec- this is an oceanography blog. Why should we worry about birds, when there are plenty of ornithologists out there with enough enthusiasm for the entire planet? Although birds are more OverTheC than under it, ocean enthusiasts should care about IMBD even if they can’t tell a godwit from a pelican. It all comes back to habitat.
As the name suggests, migratory birds cover a huge amount of territory in their annual journeys, and successfully completing those trips depends on finding healthy habitat along the way. Much like road trippers need restaurants and hotels, migratory birds require reliable sources of food and shelter when they pause to recharge. The availability of those resources can be very sensitive to human influences, and losing them has much more dire consequences than crabby passengers and backseat arguments. In the Delaware Bay, for example, an increase in horseshoe crab harvesting has reduced the number of horseshoe crab eggs. When migratory birds such as red knots stop in Delaware Bay en route to the Arctic, they can’t find as many horseshoe crab eggs and are forced to continue their long journeys without adequate food. This has resulted in a tremendous drop in the red knot population, a subspecies of which is now considered threatened under the Endangered Species Act. It’s incredible to think that a bird that flies 9,300 miles twice a year can be crippled by the overharvesting of one species in one location. Fortunately, the power of interconnectedness also means that smart environmental management can spiral into positive impacts for birds.
Habitat preservation and restoration is of the most effective ways to support migratory bird populations, and the IMBD committee has honed in on this topic as their 2015 theme. In seaboard states, relevant habitats include salt marshes and coastal wetlands, meaning that bird-centered restoration dovetails nicely with the goals of many oceanographers. For instance, marine scientists might think about improving juvenile fish habitat when they restore a wetland, but thanks to the domino effect of ecology, wetland restoration = more fish = happier migrating birds. Research has found that most migratory birds are remarkably consistent, returning to the same breeding grounds year after year. Since birds follow predictable patterns, they need to find healthy habitats at their annual pit stops.
Migrating birds travel aerial highways known as flyways, shown in glorious technicolor above. Here in eastern North Carolina, we sit on the Atlantic Flyway, which runs along the Atlantic Coast up to Greenland and the Arctic Tundra. More than 500 species of birds travel along this flyway, and they benefit from habitat restoration projects in areas such as Pine Island in the Outer Banks. But habitat can become more bird-friendly even in places with more bagels than seagulls. (And if you don’t know the associated joke, please ask the nearest first-grader.) New York State recently announced that it will be dimming overnight lights in state-owned buildings, in an attempt to reduce overall light pollution that could disorient migrating birds. Urban ecology is part of our landscape, and therefore just as necessary to include in habitat improvement initiatives.
Even if you don’t see a single migratory bird today (my condolences), your spirits can fly high knowing that incrementally improving local ecosystems keeps our birds chirping!