Double-striped thick-knee

Appearance

The double-striped thick-knee is a medium-large wader with a strong black and yellow bill, large yellow eyes, which give it a reptilian appearance, and cryptic plumage. The scientific genus name refers to the prominent joints in the long greenish-grey legs, and ''bistriatus'' to the two stripes of the head pattern.

The adult is about 46 to 50 cm long and weighs about 780 to 785 g . It has finely streaked grey-brown upperparts, and a paler brown neck and breast merging into the white belly. The head has a strong white supercilium bordered above by a black stripe. Juveniles are similar to adults, but have slightly darker brown upperparts and a whitish nape.

The double-striped thick-knee is striking in flight, with a white patch on the dark upperwing, and a white underwing with a black rear edge. However, it avoids flying, relying on crouching and camouflage for concealment. The song, given at night, is a loud ''kee-kee-kee''.

Naming

There are four subspecies, differing in size and plumage tone, but individual variation makes identification of races difficult.

Habitat

This is a largely nocturnal and crepuscular species of arid grassland, savanna, and other dry, open habitats. The nest is a bare scrape into which two olive-brown eggs are laid and incubated by both adults for 25–27 days to hatching. The downy young are precocial and soon leave the nest.

Food

The double-striped thick-knee eats large insects and other small vertebrate and invertebrate prey. It is sometimes semi-domesticated because of its useful function in controlling insects, and has benefited from the clearing of woodlands to create pasture.