A small, slender bird of prey, with long, pointed wings, the Amur falcon is noteworthy for undertaking one of the most arduous annual migrations of any bird of prey. The male is a largely dark grey bird, with a chestnut lower belly and thighs, and a white underwing, visible in flight. The dark plumage contrasts with the bright orange-red legs and facial skin, and the orange base to the beak. The female is similar in size to the male, but differs markedly in plumage, having cream or orange underparts, with dark streaks and bars, grey upperparts with a slaty-coloured head and cream forehead, and bars and spots on the wings and tail, which have broad, dark tips. The cheeks and throat are plain white, and the face bears a dark eye patch and ‘moustache’. The juvenile resembles the female, but may be paler, with reddish-brown or buff edges to the feathers. Interestingly, the Amur falcon is one of only a few birds of prey to have white claws. Once considered a subspecies of the red-footed falcon, Falco vespertinus, differences in the plumage, body shape and range of the Amur falcon have led to its classification as a separate species.