Address for correspondence: Sea Mammal Research Unit, University of St. Andrews, Fife IV11 8LB, Scotland, UK.
REDUCTIONS IN OXYGEN CONSUMPTION DURING DIVES AND ESTIMATED SUBMERGENCE LIMITATIONS OF STELLER SEA LIONS (EUMETOPIAS JUBATUS)
Article first published online: 6 MAR 2007
Marine Mammal Science
Volume 23, Issue 2, pages 272–286, April 2007
How to Cite
Hastie, . G. D., Rosen, . D. A. S. and Trites, . A. W. (2007), REDUCTIONS IN OXYGEN CONSUMPTION DURING DIVES AND ESTIMATED SUBMERGENCE LIMITATIONS OF STELLER SEA LIONS (EUMETOPIAS JUBATUS). Marine Mammal Science, 23: 272–286. doi: 10.1111/j.1748-7692.2007.00118.x
- Issue published online: 6 MAR 2007
- Article first published online: 6 MAR 2007
- Received: 11 July 2005Accepted: 29 September 2006
- diving metabolism;
- diving physiology;
Accurate estimates of diving metabolic rate are central to assessing the energy needs of marine mammals. To circumvent some of the limitations inherent with conducting energy studies in both the wild and captivity, we measured diving oxygen consumption of two trained Steller sea lions (Eumetopias jubatus) in the open ocean. The animals dived to predetermined depths (5–30 m) for controlled periods of time (50–200 s). Rates of oxygen consumption were measured using open-circuit respirometry before and after each dive. Mean resting rates of oxygen consumption prior to the dives were 1.34 (±0.18) and 1.95 (±0.19) liter/min for individual sea lions. Mean rates of oxygen consumption during the dives were 0.71 (±0.24) and 1.10 (±0.39) liter/min, respectively. Overall, rates of oxygen consumption during dives were significantly lower (45% and 41%) than the corresponding rates measured before dives. These results provide the first estimates of diving oxygen consumption rate for Steller sea lions and show that this species can exhibit a marked decrease in oxygen consumption relative to surface rates while submerged. This has important consequences in the evaluation of physiological limitations associated with diving such as dive duration and subsequent interpretations of diving behavior in the wild.