Curlew, Eskimo

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Curlew, Eskimo

Numenius borealis

phylum: Chordata

class: Aves

order: Charadriiformes

family: Scolopacidae

status: Critically endangered, IUCN Endangered, ESA

range: Argentina, Brazil, Canada, Chile, French Guiana, Guyana, Paraguay, Suriname, USA, Uruguay

Description and biology

Curlews are large shorebirds. The Eskimo curlew is the smallest of the American curlews. It averages 11.5 to 14 inches (29 to 35.5 centimeters) in length. The feathers on its back are dark brown while those on its breast are lighter. Its throat is almost white in color. The upper part of its breast and the underside of its wings are marked with dark brown streaks. Its legs are gray and its eyes are dark brown.

Because of the fat layer it builds up for winter migration, the Eskimo curlew is also called the prairie pigeon or the doughbird. Its 2-inch (5-centimeter) black, curved bill is rich in nerve endings. When the bird sticks its bill in the ground to feed, these nerves detect vibrations caused by underground insects and worms. It also feeds on snails and berries.

Eskimo curlews begin breeding in May and June. A female lays 3 to 4 green-brown eggs in a nest of straw and leaves. The nest is hidden in a hollow in the ground. She then incubates (sits on or broods) the eggs for 18 to 30 days. After hatching, the young chicks are cared for by both parents until they fledge (develop flying feathers).

Habitat and current distribution

During breeding season, Eskimo curlews inhabit arctic tundra. In winter, they are found in the pampas (partly grassy, partly arid plain) of central Argentina. While migrating northward, they inhabit the tall grass prairies of the Mississippi valley.

Since the 1980s, there have been no confirmed sightings of Eskimo curlews. Many wildlife biologists (scientists who study living organisims) consider the species to be extinct. If there are any Eskimo curlews remaining in the wild, the population is extremely low.

History and conservation measures

At the beginning of the nineteenth century, Eskimo curlews numbered in the millions. But intense hunting of the bird as it migrated quickly reduced its population. The conversion of pampas and prairies into farmland also reduced its habitat and food supply. By the early twentieth century, it was thought to be extinct.

After sightings of Eskimo curlew flocks were reported in Canada and the United States in the 1980s, a recovery program was developed. Soon after, however, the sightings stopped.