Conservation status of birds in Aotearoa New Zealand, 2021 / Hugh A. Robertson, Karen A. Baird, Graeme P. Elliott, Rodney A. Hitchmough, Nikki J. McArthur, Troy D. Makan, Colin M. Miskelly, Colin F. J. O’Donnell, Paul M. Sagar, R. Paul Scofield, Graeme A. Taylor and Pascale Michel.