Increases in the numbers of breeding pairs in two populations of Buller’s Albatross (Thalassarche bulleri bulleri)
P. M. Sagar A C and J.-C. Stahl BA National Institute of Water and Atmospheric Research, PO Box 8602, Christchurch, New Zealand.
B Museum of New Zealand, Te Papa Tongarewa, PO Box 467, Wellington, New Zealand.
C Corresponding author. Email: p.sagar@niwa.co.nz
Emu 105(1) 49-55 https://doi.org/10.1071/MU04032
Submitted: 22 June 2004 Accepted: 11 February 2005 Published: 31 March 2005
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 13 625 pairs.
Acknowledgments
We thank all those albatross counters who have assisted with this program since 1997: Jonathan Banks, Niall Broekhuizen, Phred Dobbins, Don Geddes, Don Hadden, Sue Lake, Janice Molloy, Matthias Retter, and Bernard West. Thanks also to Jeremy Carroll, Pete McClelland and Peter Tyree, of Southland Conservancy, Department of Conservation, for their support and assistance in getting us to the Solander and Snares Islands. An earlier version of this paper was improved by comments from two anonymous reviewers. This research was funded by the Foundation for Science, Research and Technology (NZ), under contract CO1X0008, and the Department of Conservation.
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