Which marine mammal holds the record for the deepest recorded dive, reaching nearly 3,000 metres?

Cuvier's beaked whale holds the record for the deepest recorded dive by a marine mammal, reaching 2,992 metres.

This small, robust beaked whale lives in deep waters across much of the world’s oceans. In 2014, a satellite-tagged individual off the coast of California descended to 2,992 metres and remained underwater for about 138 minutes. Another tagged whale produced a dive lasting more than three hours, showing the extraordinary endurance of the species.

Cuvier’s beaked whales feed mainly on deep-sea squid and fish. They use echolocation to find prey in darkness, where sunlight cannot penetrate. Their bodies also show adaptations for deep diving, including collapsible lungs, high concentrations of oxygen-storing myoglobin in muscle, and the ability to manage pressure-related changes.

The record is sometimes confused with the sperm whale, which is also an exceptional diver and has historically been credited with very deep dives. However, the deepest reliably recorded marine-mammal dive belongs to Cuvier’s beaked whale. The species is difficult to study because it spends little time at the surface.