Whimbrel (Numenius phaeopus)

Whimbrels were once quite common throughout most of their range, but populations declined in the latter half of the 19th century, probably due to environmental factors.

Description

Male and female whimbrels are similarly coloured, but females are slightly larger than males. The wings and back of adults are greyish-brown, while the underparts are grey streaked with brown. Two brown stripes pass over the top of the crown and a dark stripe extends through the eye. The whimbrel is a large shorebird, 38-48 cm in length- about as large as a crow. It has long legs and is most easily identified by its very long, distinctly down-curved bill.

Distribution

Whimbrels are found in limited areas along the coast of Hudson Bay and the far western Arctic coast to Alaska. Migrating adult whimbrels pass through the Great Lakes region at least a week before juveniles.

Ecology

Whimbrel nests are saucer-shaped depressions on top of moss or grass. The nest is always in a wet or low place in the tundra where the bases of the moss or grasses are surrounded with water.

The whimbrel eats a large number of aquatic invertebrates, especially crustaceans and insects. It also eats worms and molluscs, as well as a few seeds and leaves. In late summer, berries become an increasingly important part of its diet, as insect populations begin to dwindle. Whimbrels feed mostly by gleaning- picking up food from the ground- but also use their bills to probe into soft substrates. They are able to consume relatively large prey, tearing it to pieces before swallowing it. Muddy food items are sometimes rinsed in the water before being eaten.

Adult whimbrels have few predators, but are occasionally eaten by red foxes or by large raptors. During migration, predation on whimbrels is negligible, due to their vigilance. This species readily associates with other shorebirds, and often acts as a sentinel species, spotting an approaching predator before other birds in a mixed flock. Whimbrels are somewhat tamer than other migrating shorebirds; adults often respond to human imitations of their calls, and juveniles may approach humans quite closely.