Census of the Southern Giant Petrel population of the Falkland Islands 2004/2005

Abstract

A complete census was taken of all colonies of Southern Giant Petrels Macronectes giganteus within the Falkland Islands in 2004/05. The breeding population of the islands was estimated to be approximately 19,529 pairs (range 18,420–20,377). Southern Giant Petrels were found to breed in 38 locations around the islands, with colony size varying from one to 10,936. The majority of colonies were concentrated around the south of Falkland Sound, and to the west of West Falkland. Whilst there has been no previous census of the total population of the islands, there is a strong indication that the population has increased since the 1950s. The reasons for such an increase in population remain unclear in light of current knowledge. Development of our understanding of the breeding biology and demography of this species in the Falkland Islands is necessary, as is the need to conduct such a census every five years, with a few key colonies to be monitored every season. From the results obtained here, the conservation status of the Southern Giant Petrel, currently listed as ‘Vulnerable’, could be downgraded to ‘Near Threatened’.