- How far can a beaver swim underwater? Was put together because we noticed there was some activity on a small beaver dam in Steep Creek near the Mendenhall Glacier area in Juneau.
- There is a small culvert under the road that the beaver could go through to reach the dam on Steep Creek.
- The distance from its lodge to the culvert is 304 feet. Since the pond was completely frozen and covered with snow it appeared it would have to swim the entire distance under the ice.
- Mary Willson told me that:
The book by Muller-Schwarze and Sun (2003) says they can stay underwater for usually up to 5-6 minutes, with 15 minutes being the limit. They cite Irving and Orr 1935 (the diving habits of the beaver. Science 82:569. They have the typical mammalian diving reflex: when the head in underwater, the heart rate slows down, and most of the blood goes to brain and heart. They can tolerate high concentrations of CO2 in the tissues, but do not have great O2 storage capacity. However, when they surface again, they can exchange up to 75% of the air in the lungs (way more than humans).
