Moult energetics of the northern elephant seal (Mirounga angustirostris)

Open Access
Publisher Website
Google Scholar
Abstract
Northern elephant seals, Mirounga angustirostris, undergo an annual moult during which they shed all of their pelage and underlying epidermis. Moulting takes place on land and lasts a mean of 32.0±6.6 days. During this time the mean mass loss of adult females was 24.7±6.1%. Mean body composition at arrival (25.6±4.8%fat) did not differ significantly from that at departure (24.9±3.2%fat). Fat catabolism accounted for 93.6%of derived energy and 41%of mass lost. Approximately 3.5%of total mass loss was associated with the shedding of the pelage and epidermis. Moulting female northern elephant seals express an average daily metabolic rate of 2.0±0.6 times that predicted for adult terrestrial mammals. This energy demand was met by losing 3.0 kg d‐1 of total body mass. These energy expenditures suggest that, similar to data for harbour seals, the moult period is a time of relatively low energy expenditure.