abstract
Population estimates of fur seals were obtained at the Prince Edward Islands during the 1987/88 and 1988/89 austral summers. The populations of Arctocephalus tropicalis at Marion Island and Prince Edward Island are increasing at a rate of 12,9% and 9,7% respectively. The Marion Island population is still in the recolonization phase of rapid growth while the Prince Edward Island population is either still in the slow establishment phase or approaching maturity. The lack of previous data for Prince Edward Island prevents a comparison of growth rates. An apparent slowing of the rate of population growth in A. gazella at Marion Island is conceivably the result of undercounts in 1974, giving an overestimate of growth between 1974 and 1981. As a result of this undercount the importance of immigration to A. gazella numbers at Marion Island may have been overemphasized previously. The apparent failure of the A. gazella population to move past the slow establishment phase may be a result of the absence of krill (Euphausia superba) in the vicinity of the Prince Edward Islands. Hybridization between the species is continuing.
