Contribution of Specific Dynamic Action to Heat Balance and Thermoregulation in the Sea Otter Enhydra lutris

Specific dynamic action (SDA), measured in three sea otters using indirect calorimetry, is 10.0%–13.2% of the ingested clam or squid energy. Sea otter SDA is intermediate in magnitude and shorter in duration than reported for marine mammals that were fed fish. The postprandial peak increase in resting V̇o2, was 54% higher than postabsorptive values. This peak occurred 82 min after the otter ate 0.84 kg of squid or clam. The V̇o2 returned to postabsorptive levels 4–5 h after feeding. The short duration rise in metabolism attributable to SDA may contribute to thermoregulation at rest and correlates with field observations of resting and foraging behavior.