The Diving Physiology and Capabilities of Breath-Hold Divers - 2016 SF Bay ACS Presentations

The diving physiology and capabilities of breath-hold divers are crucial to their role in the ecosystem and their ability to exploit prey resources. During forced submersion, severe bradycardia (heart rate reduced to below resting) results in isolation of muscle and peripheral organs from blood flow, therby conserving blood oxygen for the heart and brain. However, with the development of bio-loggers, studies on trained and freely diving animals indicate that this 'dive response' is variable and often moderate. I will present my research investigating the dive response and oxygen management strategies in wild California sea lions and captive harbor porpoises using bio-loggers that measured blood oxygen, heart rate, and dive behavior during natural dives. I will discuss how sea lions and porpoises are able to optimize the amount of oxygen they take on a dive, and how the management of the oxygen differs depending on dive duration.

Speaker: Birgitte McDonald