Whitewinged chough

Corcorax melanorhamphos subfamily

Corcoracinae taxonomy

Corcorax melanorhamphos Vieillot, 1817. Monotypic. other common names

English: Black jay, black magpie; French: Corbicrave leucop-tere; German: Drosselkrähe; Spanish: Chova de Alas Blancas.

physical characteristics

Choughs are large sooty black birds with long, curved, black bills, long tails, and large white wing patches that are visible in flight. They have red eyes that become brighter during displays when wings and tail are fanned out and moved up and down. Males and females have similar plumage. Juveniles are fluffier, with brown eyes that change to red over four years. Adults are 17-19 in (43-47 cm) long and weigh 11-12 oz (320-350 g).

conservation status

Not threatened.

significance to humans None known. ♦

distribution

Choughs live in southeastern Australia. habitat

Open woodland with leaf litter and not much understory. behavior

Choughs live in groups of about four to 20 birds. Groups usually consist of a breeding pair with offspring from previous years, though small groups of unrelated birds may come together. Groups sometimes even kidnap juveniles from other groups—the bigger the group the better! Chough are excitable and noisy in their interactions within the group, and the whole group joins in to dive-bomb intruders.

feeding ecology and diet

Choughs forage together on the ground, tossing aside leaf litter, probing with their bills and sifting through the soil for insects, worms and other ground-dwelling prey. Rob Heinsohn found that choughs take an unusually long time to learn to forage: juveniles remain dependent on parental care for longer than most other birds, and their foraging skills continue improving over the first four years of life.

reproductive biology

Choughs are unable to raise young successfully unless they have help; large groups communally raise all chicks in the brood, while small groups only manage one or two. This cooperative breeding is primarily due to foraging constraints because small groups raise more chicks if they are given supplementary food. For young choughs, whose own foraging skills are still developing, helping at the communal nest is costly. Chris Boland and co-workers found that if no other group members are around when they deliver food to the nest, young birds are likely to swallow it themselves instead of feeding it to the chicks.

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