Abstract: Northern fur seals (Callorhinus ursinus) continue to dive and forage during foraging trips in cold water. Although their dense fur may prevent a decrease in body temperature, they must spend considerable time grooming to maintain a layer of trapped air in their fur. This study examined grooming and shaking behaviours, which are high-energy cost movements, using an acceleration data logger to accurately estimate the energy budget of these aquatic mammals. The authors examined the consistency between the behavioural records obtained using an animal-borne acceleration data logger and video observations of a captive northern fur seal. Grooming behaviour was defined as rubbing the body with its flippers with rolling that was occasionally associated with shaking. Grooming behaviour was detected by low-frequency components of lateral and dorsoventral acceleration resulting from rolling and high-frequency components of lateral acceleration resulting from rubbing and shaking. These observations show that the grooming and shaking behaviours of northern fur seals can be accurately detected using an acceleration data logger. We suggest that the energy budgets of free-ranging northern fur seals can be more accurately estimated using an index of energy costs and benefits captured using an acceleration data logger.
Key Words: acceleration data logger, grooming behaviour, northern fur seal, Callorhinus ursinus, energy cost
Document Type: Research article
DOI: 10.1578/AM.39.4.2013.378
Page Numbers: 378-384