Gould's petrel, Pterodroma leucoptera leucoptera, breeds only on Cabbage Tree Island, New South Wales.
Annual surveys to estimate the size of the breeding population and the reproductive output were conducted
between 1989 and 1992. Annual estimates of the total number of pairs breeding in the two gullies
containing the main population were between 122 +/- 20 (s.e.) and 202 +/- 26. Breeding success was less than
20% between 1989 and 1991, but rose to 24.7% in 1992. This marginal improvement may be the result of
management action undertaken to reduce mortality of breeding adults and fledglings. The total population is
estimated to have declined from 2004 (95% confidence limits: 1464,3185) in 1970 to 1479 (1250,1815) in
1992, a decline of 26% in 22 years. The reasons for this decline are unclear.