Nene Branta sandvicensis
Sometimes written Nēnē and often known as Hawaiian Goose, this species is endemic to the Hawaiian Islands. Captive birds are often found in wildfowl collections, and that is the source of all my photos so far.
captive Nene(s?) (with Barnacle Geese), St James's Park (London, UK), 15th July 2013
captive Nene, Pensthorpe (Norfolk, UK), 9th March 2014