Eskimo Curlew (Numenius borealis)

Eskimo Curlew

[order] CHARADRIIFORMES | [family] Scolopacidae | [latin] Numenius borealis | [UK] Eskimo Curlew | [FR] Courlis esquimau | [DE] Eskimo-Brachvogel | [ES] Zarapito esquimal | [NL] Eskimo-wulp

Subspecies

Monotypic species

Physical charateristics

29-34 cm. Small cinnamon-coloured curlew. Similar spp. Little Curlew N. minutus is similar, but N. borealis is larger, longer winged (extending beyond tip of tail), shorter legged, cinnamon not buffish below with heavily barred breast and “Y” shaped marks on flanks. Small size (25% smaller than Whimbrel N. phaeopus) eliminates all other species. Voice Flight call reportedly a rippling tr-tr-tr and a soft whistle bee bee.

wingspan min.: 0 cm wingspan max.: 0 cm
size min.: 30 cm size max.: 35 cm
incubation min.: 0 days incubation max.: 0 days
fledging min.: 0 days fledging max.: 0 days
broods: 1   eggs min.: 3  
      eggs max.: 5  

Range

North America : nc

Habitat

Members of this species bred on the tundra of western arctic Canada and Alaska

Reproduction

Nesting probably occurred in June. Nests were located in open areas on the ground and are difficult to locate. They were made of wisps of dried grass or leaves. The eggs are green with brown splotches. This species’ specific incubation behavior is unknown. It is not certain which sex if not both incubated, and what the specific timeline was. These birds evidently did not attack intruders approaching their nests, which provides reason to believe that their nests were far apart from each other.

Feeding habits

Eskimo Curlews picked up food by sight, as well as feeding by probing. They ate mostly berries while on the fall migration in Canada. During the rest of their migration and on the breeding grounds they ate insects. Snails and other invertebrate were also part of their diet during migration.

Conservation

This species has not been recorded with certainty since the early 1980s (and none have been confirmed on the wintering grounds since 1939). It was formerly abundant, but declined rapidly over a century ago as a result of hunting and habitat loss. However, it cannot yet be presumed to be Extinct until all potential breeding areas have been surveyed, and the series of occasional unconfirmed reports ceases. Any remaining population is likely to be tiny, and for these reasons it is treated as Critically Endangered (Possibly Extinct).
Numenius borealis bred at (and presumably between) the Bathurst peninsula and Point Lake in Northwest Territories, Canada. Birds migrated across Hudson Bay to Labrador (and New England, USA), and through the Caribbean to Argentina (especially the Pampas), and possibly Uruguay, Paraguay4, southernmost Brazil and Chile south to Patagonia. The return migration was probably along the Pacific coast, through Central America, across the Gulf of Mexico to the Texas coast and northwards through the prairies. It probably numbered hundreds of thousands, but declined rapidly in the 1870s-1890s to become very rare in the 20th century. The last irrefutable record was of a specimen collected in Barbados in 1963, but there is an accepted record of a flock of 23 in Texas in 1981. Since then there have been no confirmed records (none from the wintering grounds in South America since 1939), only several unconfirmed reports during 1987-2006. The population (if one persists) must be tiny.
Eskimo Curlew status Critically Endangered

Migration

It bred (May-August) in treeless arctic tundra at 180-335 m, comprising grassy meadows with birch (Betula) and sedge (Carex)2. On autumn migration (July-October), it favoured ericaceous heath, crowberries Empetrum nigrum, pastures and intertidal flats. Winter habitat was possibly wet pampas grasslands, intertidal and semi-desert areas. On return migration (March-May), it favoured burnt areas in tall grass and mixed-grass prairies, and rocky mountain grasshopper Melanoplus spretus was a key food source. It was gregarious, with traditional autumn migration sites.

Distribution map

Eskimo Curlew

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