Deep-Diving California Sea Lions: Are They Pushing Their Physiological Limit?
Abstract
This project will contribute to our understanding of oxygen management and the underlying physiological mechanisms of oxygen management in marine mammals. This information is essential if we are to interpret and understand the limits of dive performance, foraging ecology, and the ability of breath hold divers to adapt to environmental change and disturbance. The concept that most dives are aerobic in nature and do not exceed an aerobic dive limit (ADL - dive duration associated with the onset of post-dive blood lactate accumulation) has dominated the interpretation of dive behavior and foraging ecology over the past 30 years (Kooyman et al., 1980; Costa et al., 2001). However, because of technical difficulties, the ADL has rarely been measured. Instead, researchers have had to resort to estimations of total O2 store depletion, i.e., calculated ADLs (cADLs) (Costa et al., 2001; Weise and Costa, 2007). In this study we will determine the rate and magnitude of O2 store depletion during dives, and investigate its relationship to heart rate and workload, thereby improving our understanding of O2 management during diving, specifically the role of lung O2 stores and O2 delivery to tissues.
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 30, 2012
- Accession Number
- ADA573788
Entities
People
- Birgitte I McDonald
- Paul J. Ponganis
Organizations
- Scripps Institution of Oceanography