WatchList Species Account for Eskimo Curlew
(Numenius borealis)


Qualifies for the list as a Red List Species

 

Eskimo Curlew
Photo: USFWS

The Eskimo Curlew once bred on the treeless tundra of the arctic and subarctic of Canada and Alaska, and wintered in the grasslands of southern South America. The species declined suddenly between the 1870s and 1890s; where it had once had a population in the hundreds of thousands, sightings became very rare, with four birds reported from Argentina in 1990 and at least four apparently reliable reports since 1987 along the Texas coast.

 

Several theories to explain the species’ extremely rapid demise have been proposed, among them unregulated market hunting, loss of habitat due to fire suppression, and conversion of the bird's spring migration stopover sites to agricultural fields. The rapid extinction of one of its main food sources, the Rocky Mountain grasshopper, also doomed the curlew.

 

These factors were compounded by the curlew’s social system; the species was long-lived and had a single four-egg clutch, so was especially vulnerable to changes in weather and predation on its arctic breeding grounds.

The Eskimo Curlew apparently relied on relatively few stopover sites during migration, and had one of the longest and most demanding migrations of any shorebird.

 

It is postulated that the loss of a single stopover site can have great effects on some migratory species, and during the 19th century it is likely that this curlew lost several. In that century there was also a marked climate change throughout the Arctic. A few Eskimo Curlews may still exist, but in such low numbers that it may be impossible for the birds to locate mates on their vast arctic breeding grounds.