Population Increase in the Amsterdam Island Fur Seal Arctocephalus Tropicalis at Gough Island

Abstract

Population size of Arctocephalus tropicalis on Gough Island was determined by direct censuses of parts of the coast during the summers of 1974 – 1976 and 1977 – 1978 and correction factors for undercounting and seasonal cycles were applied. Present population size is approximately 200 000, giving an intrinsic rate of increase of 15,9% per year since 1955/56, but is now approaching the negative acceleration phase in population growth as a result of optimal breeding space becoming limited. An extension of breeding colony sites has also occurred since 1955.