Researching Shorebird Decline

Shorebirds are in decline worldwide – not just red knots or piping plovers, and not just shorebirds in the eastern Pacific. Migratory shorebirds all over North America are declining, including common species. One reason why may be coastal development.

The populations of nearly all of North America's 55 shorebird species are declining - including most of the 35 that spend time in New England - in large part because of disturbance to their beachfront habitats. Every flap of their wings to evade beach walkers, all-terrain vehicles, or dogs depletes more of the energy they need for long flights, leading to lower reproductive success and even death, specialists said.

That means that as New Englanders flock to the beaches, they are forcing out flocks of Atlantic shorebird mainstays.

Wildlife conservationists are responding with banding and tracking programs to discover which areas are the most critical to preserve or restore and what the shorebirds' needs are.

Most shorebirds - a category that does not include waterbirds like gulls or terns - are long-distance migrants. At the extreme, they travel as much as 18,000-19,000 miles twice a year, said Brian Harrington, a Manomet senior shorebird scientist. Their paths usually take them south along the Atlantic coast this time of year and north through the central United States in spring....

"One of the challenges is that these things are just flying all over the hemisphere," said Harrington, one of the godfathers of the shorebird conservation movement. "So to figure out the needs of these birds - sorting out the 'why' - requires this huge geographic understanding of the populations, and nobody really has that." ...

The article mentions research programs in several places and for a few species, including the oystercatcher banding study that Birdchick mentioned yesterday. One of the projects involves population surveys in the Arctic NWR.

To get better data, Stephen Brown, Manomet's director of shorebird research and conservation, is currently in the Arctic National Wildlife Refuge in Alaska, surveying and determining the nesting density of shorebirds.

"We're in the process of building a North American-wide monitoring program," he said before he left. "But funding has been limited and you can imagine how difficult it is to track birds across the arctic."

Figuring out what is ailing species that migrate over (at least) two continents is no doubt a large and complex problem. Coastal development and harassment from beachgoers is certainly a possible contributor. As we have seen with red knots, food supply during migration can be another cause for decline. Climate change is likely to become a factor as well, if it is not already.

Globe Staff Photo / Mark Wilson

On a lighter note, the dowitcher at the center of the photograph accompanying the article appears to be levitating. (See also the shorebird image gallery.)