Population size and trends within the two populations of Southern Buller's Albatross Diomedea bulleri bulleri

Abstract

The abundance and distribution of Southern Buller's Albatross ( Diomedea bulleri bulleri) were investigated at the Solander Islands in February 1996 and at The Snares in March 1997. The total breeding population of this endemic subspecies was estimated at 11 502 breeding pairs. At the Solander Islands, a total of 2625 occupied nests was estimated from aerial and ground counts in the first accurate census that included all islands in the group. Comparisons with the number of chicks counted on Little Solander Island in 1985 indicated a possible decrease of 18.7% or no change in the numbers of breeding pairs during the period 1985–1996. At The Snares, a total of 8242 occupied nests was counted and a further 635 were estimated on North East Island, Broughton Island, and associated islets and stacks. A comparison with the numbers of occupied nests counted on North East Island, The Snares, during 1969 and 1992 indicated population increases of 78% and 8% during the periods 1969–1992 and 1992–1997, respectively. Differences in the rates of change within The Snares population demonstrate the complexity of population parameters within a single seabird species, thus emphasising the need for careful formulation of conservation measures.