Eskimo Curlew

The Eskimo curlew, Numenius borealis, also known as the northern curlew, is a small member of the curlew family Scolopacidae. It was once a common sight in the tundra of western Arctic Canada and Alaska. This bird, approximately 30 cm in length, was known for its long, downward-curved bill and mottled brown plumage, with lighter brown underparts and cinnamon wing linings visible in flight.

Identification Tips

Adult Eskimo curlews can be identified by their long dark greyish legs and slightly downward curved bill. Their upperparts are mottled brown, while the underparts are a lighter brown. In flight, one can observe the cinnamon color of their wing linings. The most reliable way to distinguish them from similar species is by noting the unbarred undersides of their primaries. Their calls, though not well-documented, include clear whistling sounds.

Habitat

The Eskimo curlew was known to breed on the tundra of western Arctic Canada and Alaska.

Distribution

This New World bird migrated to the Pampas of Argentina in the late summer and returned in February. Historically, they were rare vagrants to western Europe, with no recent records. Their migration routes once took them from the Yukon and Northwest Territories, along the northern shore of Canada, then south over the Atlantic Ocean to South America for the winter.

Behaviour

The Eskimo curlew's migration was a remarkable journey, with the birds flying east along the northern shore of Canada before heading south over the Atlantic to South America, and then returning north through the Great Plains.

Diet and Feeding

Eskimo curlews were visual foragers, picking up food by sight and probing. They primarily consumed berries during the fall migration in Canada, while insects formed the bulk of their diet on the breeding grounds and during the rest of their migration. They also consumed snails and other invertebrates, including the now-extinct Rocky Mountain locust.

Breeding

Nesting likely took place in June, with nests made of dried grass or leaves on open ground. The eggs were green with brown splotches. The specifics of incubation behavior, including which sex incubated the eggs or the duration, remain unknown.

Conservation status

The Eskimo curlew is considered Critically Endangered or possibly extinct, with no reliable sightings since 1987 and no confirmed sightings since 1963. Once numbering in the millions, excessive hunting in the late 1800s led to a dramatic decline in their population. The species is fully protected across several countries, and hunting has been outlawed since around 1916.

Similar Species

The Eskimo curlew is similar in appearance to the Hudsonian curlew, the American subspecies of the whimbrel, but is smaller in size. It also forms a species pair with the Asian little curlew (Numenius minutus), but is slightly larger, longer-winged, shorter-legged, and warmer in plumage tone than its Asian relative.