A Cuvier's beaked whale has set a new deep-diving record for a sea mammal by plunging nearly three km below the ocean surface. The deepest recorded dive reached 2992 m, and the longest dive lasted 137.5 min.
The animals tagged for this study exhibited profound diving capabilities; however, the dive depths and durations reported here far exceed the prior records for this species. The deepest dive of 2992 m.
Diel patterns in dive behaviour were strongly evident in this dataset, confirming previous observations from short overnight deployments that this whale spends significantly more time in waters above 50 m at night than they do during the day.
Tagged whales spent significantly more time engaged in shallow diving during the day, but significantly less time above 50 m. Though deep dives were significantly deeper at night, the difference was only 142 m.
The percentage of time spent deep diving was not significantly different from day to night, suggesting whales foraged around the clock, targeting prey that did not vertically migrate.
Unlike its deep-diving rivals, the elephant seal and sperm whale, the Cuvier's beaked whale does not need a long recovery time after extended periods at the bottom of the ocean. It averages less than two minutes at the surface between dives.