Until recently, the southern elephant seal held the world record for the deepest and longest mammalian dive at more than 1.5 miles depth and 120 minutes. In March, results of a new study were published that put a new marine mammal in the lead. The Cuvier’s beaked whale’s record breaking dive lasted for 2 hours and 17 minutes and another dive’s depth was recorded at 1.9 miles depth. The nature of this species of beaked whale has made them difficult to study despite wide interest in their extreme diving capabilities. Their preference for deep water far from shore makes them a challenge to collect data from. Recently, scientists used satellite-linked tags to monitor the incredible diving behaviors of eight Cuvier’s beaked whales off of the coast of California. More than 3,700 hours of diving data was collected, a huge increase on previous studies’ short term data collection. The 1,100 individual deep dives recorded had an average depth of .87 miles and 5,600 shallow dives averaged .17 miles depth. For the Cuvier’s beaked whale’s deep dives, an average time of less than two minutes was spent at the surface between dives. The sperm whale, also known for its deep diving abilities, on average dive to about 0.6 miles and must take much longer breaks in between dives. Similarly, the elephant seal must take a long break for recovery time after each dive. Their dives are also much less frequent than the Cuvier’s beaked whale dives.
These whales seem to be particularly sensitive to acoustic disturbance as they account for the majority of recorded marine mammal strandings resulting from military sonar operations in this region. During this study, all of the whales monitored were tagged in a Navy sonar training range and spent a large portion of the time studied in these areas. Although data for the effects of prolonged sonar on these deep diving whales is largely unavailable, the scientists studying these whales find it likely that they have adapted to life with acoustic disturbance.
- by Megan Bargerhuff
Schorr, G.S., Falcone, E. A., Moretti, D. J., Andrews, R. D. (2014). First Long-Term Behavioral Records from Cuvier’s Beaked Whales (Ziphius cavirostris) Reveal Record-Breaking Dives. PLoS ONE. 10:1371.