Reproductive Behaviour of Southern Sea Lions

摘要: The reproductive behaviour of individually marked southern sea lions, Otaria byronia, was studied from 1981 to 1986, at Punta Norte, Peninsula Valdes, Argentina. Males defended territories along the high water mark early in breeding season but switched female defence as they were joined by females. females neighbours and intruders, forcefully held pre-oestrous near them. against intruders with threat displays fighting. never strayed far frequency aggressive interactions among males positively correlated number oestrus. A mean 2.8 associated each male central area peak season, some being 8-16 for a few hours. Ninety four percent that territory five or more days copulated. Copulations not observed away area. Mating success tenure on territory. first arrive had longest tenures achieved most copulations. Mean 24 (range = 15-57 days). copulations per adult 3.87 ± 3.31. Variance low; successful only 7% observed. Females gave birth 3.3 after arrival, copulated once six later then went feed 7.6 parturition. Thereafter, alternated periods feeding (X days) nursing their pups 2.3 sequester This mating strategy leads differences between other lion species. These are evident harem size, time (as manifested brief infrequent fighting), percentage breeding, low variance males.