Levin: Migrating Shorebirds
09/17/12 7:55AM By Ted Levin
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(Host) The calendar may say mid-September, but Ted Levin says that a significant segment of our feathered population has already ready been to the Arctic - and back.
(Levin) Fall bird migration across Vermont is a protracted event that actually begins in early summer. By the third week of June, a select few species of shorebirds, sandpipers in particular, have already been to the arctic or subarctic, laid and incubated eggs, ushered their brood into the security of the muskeg or tundra, and then followed their internal GPS south over Labrador and Quebec, before stopping for a rest along the muddy fringe of New England's ponds, lakes and rivers.
Eastern Vermont's Ompompanoosuc River is a tributary of the Connecticut River . Its two branches originate in Vershire and Strafford and merge in Union Village , approximately a mile north of the flood control dam and four miles northwest of where the now wider, deeper Ompompanoosuc flows into the Connecticut .
Eight miles south of this point, the hydroelectric dam at Wilder manipulates the flow of the Connecticut . Whenever Wilder Dam is open, the level of the lower Ompompanoosuc drops, exposing braids of shallow water and mud punctuated by islands of reeds and cattails. And these temporary mudflats are a great place to spot migrating sandpipers, if only for a day or two.
Greater yellowleg sandpipers are ubiquitous, noisy , and easy to spot. Their wings are dark, their tail and rump white, and their legs the color of the mid-morning sun. When they fly they move like arrows, straight and fast. They rarely gather in large numbers. Instead, they appear in groups of threes and fours or wander alone, needle-bills probing the mud for worms and mollusks or chasing small fish stranded in the shallows.
Greater yellowlegs nest in the remote, mosquito-infested subarctic, from one end of North America to the other. The male stakes out a territory and attracts a mate, who will deposit four eggs in a nest on the ground. Both birds incubate, but after the eggs hatch and the chicks are lead to the security of emergent vegetation, the newly emancipated female heads south in a first wave of migration, leaving the chicks' primary education to her mate.
On their way to coastal salt marshes, female greater yellowlegs stopover in Vermont, often along the Ompompanoosuc. A week or two later, when chicks have become more self-sufficient, breeding males depart in a second wave of migration. Then, sometime in the fall, the full-grown chicks leave Alaska and Canada in a third and final migration wave. So, f or the greater yellowlegs, fall migration may stretch from late June through early December.
By early fall, the beaches of Massachusetts or Long Island are full of migrating shorebirds. They assemble in marshes, dunes, farm fields and along the sandy coastline. But here in Vermont, they gather on the muddy rims of our lakes and rivers.
(Tag) Ted Levin is a nature writer and photographer. You can find more VPR commentaries at VPR-dot-net.