Southbound Shorebirds Start to Arrive to NY Harbor

Least Sandpiper

​By Joe Reynolds
New York Harbor Nature
 
Southbound migration for shorebirds starts early. The breeding season is short for birds that nest along the edge of the North Pole.
 
Many migratory shorebirds nest in the tundra, sometimes even above the Arctic Circle, where weather is unpredictable and often extreme. Here, there are primarly only two main seasons: a long, icy and dark winter lasting nine months and a very short, very cool summer lasting only three months. On the Autumn Equinox, approximately September 21, the sun sinks below the horizon, and the North Pole is in twilight until early October, after which it is in full darkness for the winter.
 
Birds respond to the quick arrival of winter and darkness up north by nesting early and completing the breeding season as soon as possible, before temperatures get too cold for food to be found. The first to migrate south are usually failed breeders, those with no chicks to support either from predation, severe weather or some other circumstance. Successful adult breeders may begin flying south by mid to late July.
 
The first to arrive around New York Harbor after nesting in the far north are usually the smallest member of the sandpiper family, Least Sandpipers, (Calidris minutilla). Sure enough I spotted a small number of birds last week on beaches around Jamaica Bay, Sandy Hook and in the Navesink River. 

​Least Sandpipers breed in northern bogs on the tundra where they raise three to four young birds. The young are usually cared for by both parents at first, but the female usually leaves the nest early to migrate southward before the male, sometimes departing even before the eggs hatch to beat the cold weather. The male normally remains with young sandpipers at least until the juveniles can fly, usually 14 to 16 days after hatching.
 
Least Sandpipers, who generally stopover in New York Harbor during fall migration, frequently nest in eastern Canada and migrate to the southern United States or northern South America for the winter. But fall migration is not a mad rush. Without the need to breed, the migratory pace to wintering grounds is relatively leisurely by comparison to spring migration.
 
So the birds can stay a bit longer at pit stops along their migration path to rest and refuel. Southbound migration time for shorebirds is the perfect time for people to enjoy the sight of shorebirds as they fly through New York Harbor from now until perhaps as late as the beginning of December.