The Erect-crested Penguin (Eudyptes sclateri) is the least known and studied penguin species and breeds exclusiviely on the Bounty and Antipodes Islands in sub-Antarctic New Zealand, together with the Easern Rockhopper Penguin (Eudyptes filholi). Both species suffered, for reasons so far unknown, severe population declines since the 1970ies. Rising sea surface temperatures may be at least partly responsible, as well as fisheries, but scientific proof for this is lacking. Also, land erosion particularly on the Antipodes may play a role. In a cooperation with the Tawaki Project a multi-year study has been initiated to perform accuarte population counts and investigate the foraging ecology of both species. A first expedition was conducted in late 2022, more expeditions are planned.

White, J., T. Mattern, K. Pütz, H. Mattern, D. Houston, R. Long, B.C. Keys, U. Ellenberg & P. Garcia-Borboroglu (2023) Plumage colour aberrations in erect-crested penguins (Eudyptes sclateri) on Antipodes Island. Notornis 70: 143-146