Harem choice and breeding experience of female southern elephant seals influence offspring survival

摘要: Female mammals can increase their lifetime fitness through modification of investment potential and by providing better rearing environments with improved breeding experience. We examined the relationships between reproductive behavioural decisions that female southern elephant seals (Mirounga leonina) made during season. whether mother age experience influenced success (measured as 1st-year survival probability), there was a change in choice harem size increasing age. Pups produced young mothers had lower probability than pups older mothers. A significant mean mass required an analysis both these effects on offspring survival. There positive effect mass, interaction two, pup The proportion ( 6 years old) increased (harems surveyed from 1997 to 2001). Females chose larger harems which breed they aged. demonstrated fidelity areas among successive seasons, females displaying greater breeding-site younger females. number previous attempts per within (breeding experience) significantly size. Breeding returned later season aged—we hypothesize young, subordinate gain priority advantage returning earlier. These results lend support hypothesis are advantages, terms survival, conferred successively Potential mechanisms select for improve conditions include mate selection avoidance conspecific harassment harems.