Justification 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).

Family/Sub-family Scolopacidae

Species name author (Forster, 1772)

Taxonomic source(s) AERC TAC (2003), AOU checklist (1998 + supplements), Cramp and Simmons (1977-1994), SACC (2005 + updates), Sibley and Monroe (1990, 1993), Stotz et al. (1996)

Identification 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.

Population estimate

Population trend

Range estimate (breeding/resident)

Country endemic?

<50

unset

-

No

Range & population Numenius borealis bred at (and presumably between) the Bathurst peninsula and Point Lake in Northwest Territories, Canada², and perhaps also Alaska, USA. 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 Patagonia². 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 century². 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 1982-2006^2,5,6,7,9. The population (if one persists) must be tiny².

Ecology: 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 flats². Winter habitat was possibly wet pampas grasslands, intertidal and semi-desert areas². 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 source². It was gregarious, with traditional autumn migration sites².

Threats Spring hunting in North America partially explains the species's near-extinction, but there was no recovery after hunting was outlawed and abandoned in c.1916². The main cause is almost certainly the near total loss of prairies to agriculture, compounded by the suppression of prairie wildfires and the extinction of M. spretus². The widespread conversion of the pampas began after the main decline, but has hindered any possible recovery².

Conservation measures underway CITES Appendix I. CMS Appendix I and II. It is protected in the USA, Canada, Argentina and Mexico. Its status has been fully documented, and identification details publicised². Breeding and wintering areas have been surveyed, and reported breeding sites investigated^1,2,3. An Environment Canada species recovery plan recommends that no recovery action be undertaken other than continued monitoring of reported sightings⁸.

Conservation measures proposed Continue cooperative international assessments of historical sites^1,3. Survey heath tundra along the Labrador coast during August-September and historic breeding grounds prior to the initiation of development projects³. Investigate any credible sightings³. Expand prairie habitat, and employ prescribed burnings³.

References 1. Blanco et al. (1993). 2. Gill et al. (1998). 3. C. L. Gratto-Trevor in litt. (1999). 4. R. Clay in litt. (2003). 5. M. Parr in litt. (2003). 6. C. L. Gratto-Trevor in litt. (2004). 7. R. Hoffman in litt. (2006). 8. Environment Canada (2007). 9. N. Crockford in litt. (2008).

Further web sources of information

Audubon WatchList

Text account compilers Phil Benstead (BirdLife International), Jeremy Bird (BirdLife International), Stuart Butchart (BirdLife International), Rob P Clay (Guyra Paraguay), Isabel Isherwood (BirdLife International), John Pilgrim (BirdLife International), Andy Symes (BirdLife International), David Wege (BirdLife International)

Contributors Rob P Clay (Guyra Paraguay), Nicola Crockford (Royal Society for the Protection of Birds), Robert E. Gill (US Geological Survey), Cheri L. Gratto-Trevor (Environment Canada), Randy Hoffman, Mike J. Parr (American Bird Conservancy)

IUCN Red List evaluators Jeremy Bird (BirdLife International), Stuart Butchart (BirdLife International), Andy Symes (BirdLife International)

Recommended citation BirdLife International (2009) Species factsheet: Numenius borealis. Downloaded from http://www.birdlife.org on 10/2/2010

This information is based upon, and updates, the information published in BirdLife International (2000) Threatened birds of the world. Barcelona and Cambridge, UK: Lynx Edicions and BirdLife International, BirdLife International (2004) Threatened birds of the world 2004 CD-ROM and BirdLife International (2008) Threatened birds of the world 2008 CD-ROM. These sources provide the information for species accounts for the birds on the IUCN Red List.

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