Description wikipedia

The white swamphen (Porphyrio albus), also known as the Lord Howe swamphen, Lord Howe gallinule or white gallinule, is an extinct species of rail which lived on Lord Howe Island, east of Australia. It was first encountered when the crews of British ships visited the island between 1788 and 1790, and all contemporary accounts and illustrations were produced during this time. Today, two skins exist: the holotype in the Natural History Museum of Vienna, and another in Liverpool's World Museum. Although historical confusion has existed about the provenance of the specimens and the classification and anatomy of the bird, it is now thought to have been a distinct species endemic to Lord Howe Island and most similar to the Australasian swamphen. Subfossil bones have also been discovered since. The white swamphen was 36 to 55 cm (14 to 22 in) long. Both known skins have mainly-white plumage, although the Liverpool specimen also has dispersed blue feathers. This is unlike other swamphens, but contemporary accounts indicate birds with all-white, all-blue, and mixed blue-and-white plumage. The chicks were black, becoming blue and then white as they aged. Although this has been interpreted as due to albinism, it may have been progressive greying in which feathers lose their pigment with age. The bird's bill, frontal shield and legs were red, and it had a claw (or spur) on its wing. Little was recorded about the white swamphen's behaviour. It may not have been flightless, but was probably a poor flier. This and its docility made the bird easy prey for visiting humans, who killed it with sticks. Reportedly once common, the species may have been hunted to extinction before 1834, when Lord Howe Island was settled.