The whimbrel, or Numenius phaeopus, is a large wader that belongs to the curlew species of birds. Full-grown whimbrels are 15-18 inches (37-45 cm) in length, weigh about 10.9-17.4 ounces (310-493 g) and have a wingspan of 30-36 inches (76-90 cm). In appearance, the whimbrel is gray-brown to brown, with long legs and prominent dark stripes on its head. Its most striking physical feature is its long bill, which is about 2.0-3.5 inches (5-9 cm) in length and curves downward. Although adult females have the longest bills, both sexes use them to prod deeply into the ground when looking for food.
Geographically, the whimbrel is one of the most widely distributed shorebirds in the world. There are four distinct subspecies of whimbrels, and each inhabits its own separate geographic region. One breeds in North America, with the three remaining subspecies breeding either in southern Russia, in eastern Siberia or in an arc from northwest Siberia to Iceland. The whimbrel species will nest in these arctic and subarctic areas and then, in winter, migrate to the coasts of Africa, to southern Asia as far south as Australia and to the coasts of South America or southern North America.
When it migrates, the whimbrel moves mainly along routes that go over coasts and oceans. Whimbrels migrate at night in large flocks, with the timing of the migration based upon sex and age. Females migrate first, then males and finally the juveniles. During this migration, some members of the whimbrel species might fly as far as 2,500 miles (4,000 km) nonstop.
The habitat that whimbrels prefer depends on whether they are nesting, migrating or wintering. When they nest, whimbrels like both wet and dry areas such as bogs, heath or tundra. While migrating, they prefer wet areas such as tidal flats or marshes. For wintering, whimbrels like tidal flats but also will stay in shallow marshes and short grasslands.
Their diet also depends on where they are in the migration cycle. When nesting, they eat the insects and berries that they find in the subarctic and arctic areas. When they stop along coastlines during migration, they use their long bills to probe in the sand or mud for worms, crabs or crustaceans.
Breeding season lasts from late spring through mid-summer. Nests are scraped out of either the ground or moss and are lined with leaves. The female lays three to five eggs that hatch in 24-28 days. Both parents incubate the eggs and care for the chicks.