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Eskimo Curlew Numenius borealis. By Rachel Ziska Mr. Weidert 3 rd hour. Eskimo Curlew Numenius borealis.
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Eskimo Curlew Numenius borealis By Rachel Ziska Mr. Weidert 3rd hour
Eskimo CurlewNumenius borealis The Eskimo Curlew is an upland shorebird and the smallest of the North American curlews. It is 12-14 inches long, including its 2-2.5 inch slightly de-curved bill, and has a 26-30 inch wingspread. Its general color is buff to pale cinnamon-brown, darker on the back and lighter below. There is a very light stripe over the eye. The bill is black and it has dark green legs.
Location This map of Kansas shows where in the state this bird has been known to be.
Population In the 1870s-1890s it become very rare in the 20th century. The last irrefutable record was of a specimen collected in Barbados in 1963. Since then there have been no confirmed records. Any remaining population is assumed to be tiny, as there have been no confirmed sightings since the early 1980s.
Habitat Eskimo curlews migrate from breeding grounds in the Arctic tundra through the North American prairies to wintering grounds on the Pampas grasslands of Argentina.
Food Web The Eskimo curlew’s diet consists of mainly ants, freshwater insect’s and the fruit of Black Crowberry. In the coastal areas they prefer to feed on snails. They also eat worms, and other invertebrates found on shores, they eat before and after roosting for the night. Along the Atlantic coast they eat beetles, moths, ants, spider, seeds, and other berries.
Endangered In the 19th century, flocks of Eskimo curlew numbering in the thousands were seen along migration routes. Extensive agricultural development in the Great Plains eliminated most of the tallgrass and mixed-grass prairie that was essential to the northward migration of the Eskimo curlew. Fire repression hindered the regeneration of these prairie habitats. Without key habitats and food sources, Eskimo curlews could not maintain the energy reserves necessary for their long migrations and successful reproduction. Hunting also contributed to the species' decline in the 1800s. In a manner similar to the hunting of passenger pigeons, commercial hunters shot curlews by the thousands during spring and fall migrations. When numbers of passenger pigeons became too low, hunting pressure on Eskimo curlews became even greater. New England colonists named them "dough birds" because of the great quantities of fat that they built up in their bodies prior to southerly migration.
Endangered By the early 1900s, the species was becoming rare, and only about 70 individuals have been observed in the last 50 years. No confirmed reports of Eskimo curlews have been made since the mid-1980s, despite concerted efforts to locate the birds on their breeding and wintering grounds. Several unconfirmed sightings of the Eskimo curlew have occurred during the last 20 years. Some of these birds were likely whimbrels. The most frequent sightings have been in Texas, and the most recent unconfirmed sighting occurred in 1996 in southwestern Manitoba. It is unknown whether the Eskimo curlew still exists. It is possible that populations, when reduced below a certain level, were unable to recover. The breeding grounds of this bird have remained relatively unchanged and pristine. However, migratory staging areas have changed dramatically and no longer provide sufficient food and habitat. In addition, changes to habitats in South America, while not contributing directly to the decline of the species, will likely hinder any possible recovery to a viable population level.
Endangered To preserve any chance of preventing the species' extinction, conservation measures are being implemented jointly by the governments of the United States, Canada, and Argentina. Currently, there is no recovery plan for the Eskimo curlew. However, the bird is protected by legislation in Canada, Mexico, and the United States. In the U.S. the Eskimo curlew is protected by the federal Endangered Species Act and the Migratory Bird Treaty Act. Although its breeding habitat is secure, the grasslands on which the curlew depends during winter and migration have decreased in quantity and quality. Preserving and re-creating grasslands will be essential for any conservation efforts to succeed for this species. Specifically, the Eskimo curlew needs natural tallgrass and mixed-grass prairies, with a regime of controlled burning for their regeneration, rather than cultivated farmland. In addition, some researchers have proposed a captive breeding and release program, should any adult curlews be located. However, such a program has the inherent risk of removing the last remaining birds from the wild with the possibility that they will not survive in captivity.
Biotic Potential Eskimo curlews breed in the northern Mackenzie (Northwest Canada), on wetlands north of the tree line, in open tundra and on tidal marshes. Preferred breeding habitats are fields, pastures, and the drier parts of salt and brackish marshes, as well as coastal beaches and vegetated dunes. During migration, populations move south and east to gather on the coasts of Labrador and Newfoundland before flying offshore in route to South American wintering grounds. The eskimo curlew’s nest are just a hole or depression in the ground. They are lined with decaying leaves and a thin sprinkling of hay. Both parents care for the young. The breeding is currently unknown but probably similar to that of the Little Curlew having green eggs with brown splotches.
Recovery Plan In 1916, nongame bird hunting in the United States was stopped by the Migratory Bird Treaty Act, but the Eskimo Curlew did not recover. Conversion of native grasslands to cropland, in the South American wintering area and along the migration route through the tall grass prairies of the United States, is thought to be the reason for the birds' failure to recover. There are no current plans for this bird’s recovery.