Diving record broken by beaked whale
In an amazing dive, a beaked whale has remained under the water for one hour longer than the old record. According to biologists, this should not be possible.
Biologists from Duke University have recorded by far the longest dive ever observed by a mammal. The new record of 3 hours and 42 minutes was set by a Cuvier’s beaked whale.
Over a period of five years, scientists have been placing satellite transmitters on beaked whales, observing a total of 3680 dives by 23 individuals. The dives lasted 59 minutes on average, so the record dive of 3+ hours was exceptional.
The record has surprised biologists for several reasons. Firstly it is almost one hour longer than the old record (also held by a beaked whale). Secondly, it should not be possible for a relatively small whale to remain immersed for such a long time. The beaked whale measures less than 7 metres and weighs only 2.5 tonnes, limiting the quantity of oxygen it can store in its body. In comparison, sperm whales, also known for long deep dives, weigh up to 50 tonnes, but their longest dive record is only 83 minutes.
The beaked whale has muscles with a high content of myoglobin that can store oxygen. But according to scientists’ calculations, this should run dry after 77 minutes. Subsequently, the muscles convert sugar without the use of oxygen in anaerobic metabolism, producing lactic acid that accumulates in the muscles. According to the scientists, the beaked whale must have unknown physiological mechanisms that prevent it from accumulating lactic acid.
The whale might also have other techniques to make its oxygen reserves last longer than scientists expect, such as by lowering its cardiac rhythm and metabolism, or by shutting off the blood supply to non-essential organs, leaving only the brain, heart and muscles consuming oxygen.