subspecies by overall body size and has a moderate-sized bill. It merges with subspecies macrorhynchus around the Gulf of Carpentaria. It has disappeared from much of its former range in northern New South Wales and southeast Queensland. C. b. graptogyne, (Endangered) known as the south-eastern red-tailed black cockatoo, is found in southwestern Victoria and southeastern South Australia in an area bordered by Mount Gambier to the west, Portland to the south, Horsham to the northeast and Bordertown to the north. The smallest of the five subspecies, it was only recognised as distinct in the 1980s. It is predominantly dependent on stands of Eucalyptus baxteri (brown stringybark), Eucalyptus camaldulensis (river redgum) and Allocasuarina luehmannii (buloke) for feeding and nesting. These tree species have been all threatened by land clearing and most remaining are on private land; possibly only 500–1000 individuals remain. The subspecies and its habitat are the subject of a national recovery plan. In 2007 local landowners are being reimbursed for assisting in regenerating suitable habitat. C. b. macrorhynchus, given the name great-billed cockatoo by Mathews, is found across northern Australia. Although thought to be widespread and abundant, this subspecies has been little studied. It is also large and has a large beak, as its subspecific name implies. Females lack red colouration in their tails. C. b. naso (Vulnerable) is known as the forest red-tailed black cockatoo and is found in the southwest corner of Western Australia between Perth and Albany. This form has a larger bill, and favours marri (Corymbia (formerly Eucalyptus) calophylla), jarrah (E. marginata) and karri (E. diversicolor). C. b. samueli exists in four scattered populations: in central coastal Western Australia from the Pilbara south to the northern Wheatbelt in the vicinity of Northam, and inland river courses in Central Australia, southwestern Queensland and the upper Darling River system in Western New South Wales. Birds of this subspecies are generally smaller with smaller bills than the nominate banksii. Description Red-tailed black cockatoos are around 60 centimetres (24 in) in length and sexually dimorphic. The male's plumage is all black with a prominent black crest made up of elongated feathers from the forehead and crown. The bill is dark grey. The tail is also black with two lateral bright red panels. Females are black with yellow-orange stripes in the tail and chest, and yellow grading to red spots on the cheeks and wings. The bill is pale and