Stewart Island census 1999-2000

The Yellow-eyed Penguin Trust has completed the first comprehensive baseline survey of yellow-eyed penguin nest numbers on Rakiura/Stewart Island. The Trust’s aim was to have a complete up-to-date survey of the whole island.

Survey results show a decreased population of yellow-eyed penguins on Stewart Island, with results totalling only an estimated 200 breeding pairs. In the past, penguin landing areas have been documented by the Department of Conservation and other researchers, with the 1992 estimated numbers of penguins being 470-600 pairs.

Conducted over the last two breeding seasons (1999 and 2000), this nest search census was directed by the Trust’s project officer David Blair, and included a number of experienced volunteers. The survey raises several important questions about the yellow-eyed penguin breeding population on the island. Predation by feral cats, marine food supply and disease may be the reasons for these low numbers.

In 2000, a comparison between nest counts and beach landings was made, and during both of these counts, only three juveniles were sighted, giving rise to concerns over the future survival of this population.

The Trust is currently collating results to produce a scientific publication. It is hoped this report will be a catalyst for future research into why these threatened yellow-eyed penguin numbers are so low.

The Trust invested over $20,000 into this research, which involved an estimated 253 days of work on Stewart Island. Some of this money came from our loyal supporters who return the Mainland Products Ltd cheese and butter wrappers.