The White-winged Chough (Corcorax melanorhamphos) is one of only two surviving members of the Australian mud-nest builders family, Corcoracidae, and is the only member of the genus Corcorax. It is native to Southern and Eastern Australia and is an example of convergent evolution as it is only distantly related to the European choughs that closely resembles in shape and was named after.
It is placed in the family known as the mud-nest builders or Corcoracidae, written as Grallinidae in older books before the removal of the genus Grallina to the Wagtail family. It is one of two remaining species, with the Apostlebird (Struthidea cinerea), which differs in appearance but exhibits many behavioural similarities.
It is only distantly related to the European Chough (Pyrrhocorax pyrrhocorax), and Alpine Chough (P. graculus), which are members of the crow family Corvidae. The similarities in appearance of dark plumage and downturned bill are the result of convergent evolution.
Their distinctive call, "Chough-chough-chough-chough-cough-chough!" repeated in rapid succession as they fly away, is a key defining aspect of this species, and may have been the precursor to their common name.
Choughs are territorial and highly social, living in flocks of from about 4 up to about 20 birds, usually all the offspring of a single pair.
Breeding season is from August to December. The nest is a deep cup-shaped structure made of grasses held together with mud or sometimes manure in a tree fork up to 10 metres above the ground. Three to five cream-coloured eggs sparsely splotched with dark brown and lavender shades are laid measuring 30 mm x 40 mm.
There is one report of White-winged Choughs occupying and using a nest which was likely to have been built by the Australian Magpie. However, this was unable to be confirmed as the nest was not witnessed being built.
All members of a family take turns to incubate, preen, and feed youngsters, and all cooperate in defending the nest against predators. However, the juveniles, who are highly inefficient foragers, have been observed to engage in deception; they bring food back to the nest and make to feed nestlings, but instead wait until unobserved, and then eat it themselves. This behaviour disappeared when food sources were artificially supplemented. There are three main threats to young choughs: starvation; predation by nest-robbing birds, particularly currawongs; and sabotage by neighbouring chough families anxious to protect their food supply by restricting competition. Larger family groups are better able to deal with all three threats.