New Zealand Journal of Ecology (2016) 40(1): 108- 113

Snares crested penguins Eudyptes robustus population estimates 2000–2013

Research Article
Johanna A. Hiscock 1
B. Louise Chilvers 2*
  1. Southern Islands, Department of Conservation, PO Box 743, Invercargill 9840
  2. Wildbase, Institute of Veterinary, Animal and Biomedical Sciences, Massey University, Private Bag 1112, Palmerston North 4442
*  Corresponding author

New Zealand (NZ) is an internationally significant area for penguins. All NZ penguin species are listed in ‘at risk’ threat categories. The naturally uncommon Snares crested penguins (Eudyptes robustus), which are restricted to NZ subantarctic islands, are highly susceptible to localised stochastic events and human activities. There has been uncertainty about population size and trends for Snares crested penguins. We surveyed the nest abundance and distribution of Snares crested penguins on Northeast (NE) and Broughton Islands, Snares Island group, from late September to early October in 2008, 2010 and 2013 and compared results with a survey from 2000. Counts of all nests (nests with eggs and total observed nests) within all colonies around the islands were undertaken. In 2008, 19 845 ± 29 nests with eggs and 24 666 ± 38 total nests were counted from 111 colonies. In 2010, 25 525 ± 21 nests with eggs and 30 672 ± 26 total nests from 117 colonies were counted while in 2013, 25 149 ± 39 nests with eggs and 29 009 ± 45 total nests from 119 colonies were counted. Penguin nest numbers at the Snares appear to be stable overall when compared with the 2000 survey, which gave 28 396 nests with eggs (direct counts) and 30 607 total nests from 112 colonies. However, 2008 appears to be a year with considerably lower numbers of nests compared with other years. This apparently stable population is in contrast to most other crested penguins in the world. Given the extremely restricted distribution of Snares crested penguins and potential for a rapid catastrophic decline, we recommend surveys be continued at regular intervals in order to detect a significant decline and allow management measures to be implemented if needed.