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Movements, home range, and territories of male sea otters off central California

January 1, 1989

Sixty male sea otters (Enhydra lutris) were tagged on the rear flippers with colored tags. Of these, 46 (77%) were resighted. Movements of 127 km were documented for adults and 187 km for subadults. Adults maintained breeding territories that averaged 40.3 ha (n= 10, SE = 4.0). They returned to the same territory seasonally for up to seven consecutive years. Territorial males moved from areas of high male abundance to areas of high female abundance on a seasonal basis. During the winter, 74% of adult males left breeding areas and joined concentrations of males located near the ends of the range. Thirty percent of the subadult males were observed in male groups near the extremities of the range. During the summer and fall, the density of adult males (15/1,000 ha) and adult male to independent otter (non-pup) ratio (1:5) in female areas was highest. The number of adult males in areas of female abundance was inversely related to the number of dependent pups, perhaps because when pup numbers are low (late summer and fall) the number of estrous females is high. Subadult males may remain in female areas on a year round basis until their second or third year. However, they were not generally associated with adult females.

Publication Year 1989
Title Movements, home range, and territories of male sea otters off central California
DOI 10.1111/j.1748-7692.1989.tb00330.x
Authors Ronald J. Jameson
Publication Type Article
Publication Subtype Journal Article
Series Title Marine Mammal Science
Index ID 1007481
Record Source USGS Publications Warehouse
USGS Organization Western Ecological Research Center
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