A multivariate analysis of phenotype and paternity in male harbor seals, Phoca vitulina, at Sable Island, Nova Scotia

Understanding the links between phenotype and reproductive success is criti cal to the study of the evolution of mating systems and life-history patter ns. We examined the relationship between phenotype and mating success of ma le harbor seals (Phoca vitulina concolour) at Sable Island, Canada. Cluster analyses of eight traits including mating success determined by genetic pa ternity analysis, haul-out behavior, body mass, and mass change identified four groups of males with distinct characteristics. The most successful mal es were of moderate body size, were rarefy sighted alone, were associated w ith many different groups on shore, and were sighted on the haul-out relati vely infrequently. Large males that hauled out frequently alone, previously thought to be socially dominant, were less likely to be successful. Also l ess successful were smaller, younger males. Contrary to our hypotheses, and unlike most terrestrially breeding pinnipeds, body size and reproductive e ffort were not positively associated with mating success, and some successf ul males appeared to spend considerable time foraging in deep water.