Age and sex determination from canine teeth in sea otter (Enhydra lutris)

The sexual dimorphism in the upper canine tooth diameter has been revealed using a sample of the teeth from 310 sea otters of known sex (carcasses were collected at Bering Island). The ovelapping between males and females by the canine tooth diameter was 16,32% in individuals at the age of less than or equal to 1 year and 11,42% in those of > 1 year old. The method is suggested to determine sex in the beached sea otter corpses. Age in 87 sea otters from the Kuril Islands was determined by two persons independently counting cementum annuli on undecalcified ground sections of the canine teeth. Age of 30 individuals from Prince William Sound was determined by two persons from stained sections of the decalcified first premolars and from ground sections of the canine teeth. Differences in age estimates from ground sections for 84-88% of samples varied +/- 1 year, those between estimates from stained sections and ground sections varied within +/- 2 year for 73% of samples.