Increases in the numbers of breeding pairs in two populations of Buller's Albatross (Thalassarche butteri butteri)

Abstract

The abundance and distribution of the southern subspecies of Buller's Albatross (Thalassarche b. bulleri) breeding on the Solander and Snares Islands were investigated during February—March 2002. At the Solander Islands, a total of 4912 breeding pairs was estimated from aerial and ground counts. This total compares to an adjusted total of 4147 breeding pairs estimated during February 1996 using the same methods, and indicates average annual increases of 3.1% during the period 1996–2002, compared with relatively stable numbers estimated for the period 1985–96. At the Snares Islands, a total of 8165 breeding pairs was counted on North East Island and associated islets from ground and vantage-point counts, and 8713 breeding pairs were estimated for the Snares Islands as a whole. Analysis of annual counts of breeding pairs on the North Promontory of North East Island showed an estimated increase in the breeding population of 3.2% per year. In 2002, the estimated total breeding population of Buller's Albatross at the Snares and Solander Islands was 13625 pairs.