Eskimo Curlew (Numenius borealis)

Status: Extirpated

Description: The Eskimo Curlew is a shorebird that is easily confused with its close relative the Whimbrel (Numenius phaoepus). Eskimo Curlews are approximately 36 centimetres long (12 inches) and weigh 227 grams (half a pound). They have a 5 to 6.5 centimetres long black bill that curves slightly downward. The upper portion of the bird is brown, while the breast and abdomen are buff. The crown is brown, finely streaked and may have a faint eye stripe.

The main difference between the Eskimo Curlew and the Whimbrel is size. The Whimbrel is somewhat larger and is approximately 54 centimetres (18 inches) long and weighs 600 grams (1.25 pounds). The upper portion of the Whimbrel is more of a grayish color with a distinct eye stripe. The under sides of the Eskimo Curlew’s outer wings are cinnamon coloured and unbarred, while the under sides of the Whimbrel’s outer wings are buff white and barred.

To see a comparison of the two birds go to:

http://www.npwrc.usgs.gov/resource/othrdata/curlew/identif.htm

Status: The Eskimo Curlew was listed as endangered in 1978 by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC). In the 19^th century, Eskimo Curlews were one of the most common birds in North America. Prior to 1880, their numbers were estimated in the millions. Early settlers called them prairie pigeons and flocks were reported as clouds in the sky. One flock in Nebraska reportedly covered 100 hectares (40 acres).

In earlier times, Eskimo Curlews were heavily hunted for at least 11 months of the year. Settlers found Eskimo Curlew made a delicious meal and hunters had no problem filling their demand. Eskimo Curlews traveled in very large numbers and many could be taken down with one shotgun blast. Their lack of fear of humans, combined with their habit of circling back into gun range when members of the flock were shot, allowed for thousands to be killed at a time.

The species declined rapidly between 1880 to 1895 and by 1900, Eskimo Curlews were almost extinct. In 1917, both Canada and the United States protected the Eskimo Curlew under federal laws. There were only seven sightings of Eskimo Curlew between 1970 and 1977 and no more than two were spotted at one time. Today, population estimates are rough and range anywhere between 23 to 100 birds.

In 1981, 23 Eskimo Curlews were sighted in Texas. These sightings suggest the existence of a small breeding population, although extensive searches over many years have failed to turn up any evidence of nesting Eskimo Curlew. However, any adults found nesting should be verified and well documented and the areas protected from development.

There have been several recent sightings of the Eskimo Curlew in Saskatchewan. A single bird was spotted with a flock of Lesser Golden Plovers south of Regina in 1982. Since then, two unconfirmed sightings have also been reported. Any sightings of this bird should be reported to the Fish and Wildlife Branch at 1-306-787-2314.

Habitat and Life Cycle

The Eskimo Curlew has been encountered in every Canadian province except British Columbia and the Yukon. However, it is believed the bird passed through the Yukon, since it appeared in both the North West Territories and Alaska.

The Eskimo Curlew arrived at the breeding grounds on the tundra and woodland transition zones of the Mackenzie District located in the North West Territories in late May. Their diet consisted mainly of ants, freshwater insects and the fruit of Black Crowberry (Empetrum nigrum). Eggs were laid after the middle of June, the chicks hatched in mid July and left the nest soon after hatching.

The birds gathered at the end of July and flocked to Labrador prior to their southern migration. Their habitat for the month of August was mainly the eastern coast of Labrador and the northeastern United States. They were also seen in Newfoundland, Nova Scotia, Prince Edward Island and New Brunswick. Eskimo Curlews would stuff themselves with crowberries and insects to prepare for the 4,000 kilometre nonstop flight to South America. The Curlews would leave Canada by the end of September and unless a storm forced them inland, their entire route was over the Atlantic Ocean.

Eskimo Curlews were reported as early as mid-September in their major wintering grounds in the grasslands, or Pampas of Argentina in South America. Some may have possibly wintered in grasslands in Brazil, Chile and Uruguay. Here the Eskimo Curlew’s diet was mainly made up of insects.

Eskimo Curlews probably began their spring migration in late February or March. Their route through South America is not known, but they may have moved up the Pacific Coast to Peru or Ecuador. From there they would have crossed Central America and the Gulf of Mexico to Texas. After reaching Texas they would travel through the tall-grass and mixed-grass prairie of the Midwestern United States (Oklahoma, Nebraska, Kansas, South Dakota, southern Louisiana, Missouri, Illinois and Minnesota) to Canada. During their migration through Canada, Eskimo Curlews may have been most common in Saskatchewan but were also seen in Alberta and Manitoba.

Range Map (Historic migration patterns of the Eskimo Curlew (Numenius borealis) (Adapted from the Northern Prairie Wildlife Research Centre, 2000)

Limiting Factors: Over hunting appears to be the primary reason for the rapid decline of Eskimo Curlews. As Passenger Pigeons began to decline, hunters turned their attention to Eskimo Curlews and Golden Plovers. These birds would migrate together creating large flocks and easy hunting. On August 29, 1863, an estimated 7,000 to 8,000 birds were shot within a few days when both species arrived on Nantucket Island, Massachusetts.

There is also speculation that the loss of prairie habitat in North America may have contributed to the species decline. The conversion of native prairies into cropland probably reduced the amount of a suitable staging habitat during the bird’s migration. Similar changes to the wintering grounds in Argentina may have also contributed to the decline.

Recovery Actions:

Why the Eskimo Curlew did not make a comeback after it was protected in 1917 is not known for sure. Changes to habitat may not have directly contributed to the decline in the population of Eskimo Curlew but it most certainly affected the ability of the species to make a recovery.

Many people insist on human intervention to help the species, but it has been recommended that no captive breeding program be established. Recommendations for conserving the Eskimo Curlew do include the protection of prairie grasslands used in spring migration and of the wintering habitat of Pampas-like grasslands of South America.

Sightings of the Eskimo Curlew should be reported to the Fish and Wildlife Branch at 1-306-787-2314 and/or to the Saskatchewan Conservation Data Centre (CDC) at www.biodiversity.sk.ca.

Selected References: Please contact your local library or visit the internet sites below for more information on the Eskimo Curlew.

Environment Canada. 1999. Eskimo Curlew. [Online]

http://www.speciesatrisk.gc.ca/Species/English/SearchDetail.cfm?SpeciesID=21
Date visited: May 12, 2000

Matthiessen, Peter et al. 1967. The shorebirds of North America. p.190. The Viking Press, Inc.
New York, N.Y.

Northern Prairie Wildlife Research Center. 199?. Eskimo Curlew: a vanishing species. [Online]

http://www.npwrc.usgs.gov/resource/othrdata/curlew/history.htm
Date visited: May 18, 2000

World Conservation Monitoring Center. 1999. Species under threat: eskimo curlew. [Online]

http://www.wcmc.org.uk/species/data/species_sheets/eskimocu.htm
Date visited: May 11, 2000