Conservation and Management

Sport and market hunters posed the greatest threat to Whimbrel populations until 1916 when Canada and the U.S. signed the Migratory Birds Convention, thereby protecting this species and others. Whimbrel is considered good eating by some people, and sport hunters sought the challenge of so vigilant a bird. Numbers diminished markedly between mid- and late 1800s (Mackay 1892), although owing to its wary nature and habit of migrating in smaller flocks, Whimbrel was not slaughtered in the same excessive numbers as some large shorebirds. After 1916, numbers apparently increased (Bent 1929), although not to former levels (e.g., Peters and Burleigh 1951).

Whimbrel is still hunted for food in parts of South America (e.g., Vermeer and Castilla 1991). Destruction or manipulation of coastal wetlands and disturbance at nest and roost sites, however, now pose the greatest threats to populations (Walker 1977, Senner and Howe 1984). Some birds, possibly inexperienced breeders, desert nests readily when disturbed (J. Jehl pers. comm.); 2 of 65 nests deserted after 1–2 observer visits (MAS). Environmental contaminants are an increasing threat: analyses of Whimbrel livers and prey species along 20 km of beach contaminated by untreated mining wastes in n. Chile revealed high cadmium residues in both (Vermeer and Castilla 1991).

Important shorebird migratory staging and wintering sites are being recognized and protected through the Western Hemisphere Shorebird Reserve Network (WHSRN). Some potential areas for designation as major “hemispheric” sites are important to wintering Whimbrels: n.-central Brazil (44% of South American wintering population) and Suriname (13%) on the eastern coast; Chiloé area, s. Chile (25% of South American wintering population, but 66% of Pacific Coast population) on the western coast (Morrison and Ross 1989a, b). Coastal Mexico has no high concentrations of wintering Whimbrels (Morrison et al. 1992, 1993, 1994b). Critical sites during migration need to be identified. Because population trend is uncertain (Howe et al. 1989), monitoring is needed where large numbers congregate.