The shorebirds that we see along the New Hampshire seacoast are traveling between northern breeding areas and tropical wintering ones. Only four species actually breed along our coast (Piping Plover, Killdeer, Spotted Sandpiper, and Willet), and the rest are here for one reason: to feed. They are building up fat reserves to fuel the next leg of migration, which might entail a flight of hundreds of miles. NH Audubon first looked at shorebird use of the coast in 2006-07 and revisited this area in 2018-20 to see what might have changed. A shift in site use may indicate that shorebirds are being driven from prime foraging or roosting locations by disturbance or other threats in our narrow coastal zone.
The key area for foraging shorebirds in New Hampshire remains the tidal flats of the Hampton-Seabrook Estuary, where hundreds may congregate at low tide. As these flats are inundated, the birds shift elsewhere, with sites including Meadow Pond in Hampton and areas of seaweed (aka “wrack”) deposited on beaches the length of the coast. At the highest tides, shorebirds need a place to rest until they are able to forage again, and these roost sites are just as important as feeding areas. Some locations shifted dramatically between our two studies, including the discontinued use of pools on the periphery of the Hampton-Seabrook estuary. Instead, a significant roost has formed on a cobble beach at the north end of Hampton, where hundreds of birds pack into a narrow strip of dry ground at high tide.
Anything that compromises shorebirds’ ability to feed or causes them to waste energy may compromise migration. In this light, there is increasing concern about threats that include loss of habitat and repeated flushing by people, vehicles, or unleashed dogs. Ideally, birds can rest at their roosts undisturbed, but increasing human presence often means they are flushed more regularly, resulting in their expending some of their stored energy reserves. At the same time, changes to the coastal landscape (e.g., development and sea-level rise) can degrade roost sites and force birds to less suitable locations where they may be subject to more frequent disturbance. Clearing of wrack from beaches is another threat listed for shorebirds in the North Atlantic, since it deprives them of a valuable food source. Given this combination of threats, a key conservation action is to educate people in coastal communities about basic shorebird ecology and how best to minimize repeated disturbance.
Project Leader: Pamela Hunt
Photos, from the top: Black-bellied Plovers by Scott Heron, Semipalmated Plover by Pam Hunt.