Skull and taxidermy mount of an adult female Nubian Wild Ass (Equus africanus africanus) shot by Percy Powell-Cotton on 22 February 1934 in the Jibāl Kiltatēb (Jabal Kilaiteit) mountains of the Red Sea Province, Sudan. The complete skeleton is also in the Powell-Cotton Museum collection.

This animal was collected during Percy Powell-Cotton’s second hunting trip to Sudan, on which he was accompanied by his daughter Diana. They shot two female Nubian Wild Asses, one of which was heavily pregnant.

The Nubian Wild Ass is one of the ancestors of domestic donkeys. It historically had a wide range, from southern Egypt down through Sudan and into northern Eritrea. However, even by the late 1930s when Percy and Diana Powell-Cotton collected specimens, they were incredibly rare. Aerial surveys in the 1970s reported small numbers of Nubian Wild Asses around the border between Sudan and Eritrea, but no sightings have been made for many years and they are now probably extinct. It is thought that the last Nubian Wild Ass in captivity was a male named Righetto, who died at the Zoological Gardens in Rome in 1953.

The second subspecies of African Wild Ass, the Somali Wild Ass (Equus africanus somaliensis), is critically endangered. There are probably fewer than 200 animals remaining in the wild, in small groups in Eritrea and Ethiopia.