Cuvier's beaked whales are claimed to be the most extreme breath-holders among marine mammals.
A satellite tag attached to one of these animals, swimming off the coast of California, recorded a dive to nearly 3km below the ocean surface that lasted 137 minutes.
This performance exceeds that for any southern elephant seal, which is also known to be an extreme breath-holder.
Erin Falcone is a research biologist with the Cascadia Research Collective in Washington State, US, which led the research project.
She told BBC News that beaked whales had very high levels of the myoglobin protein in their muscles, to the point where the tissues appeared almost black.
This functions like haemoglobin in the blood, allowing the whales to store much higher levels of oxygen, and thus breathe less frequently while remaining active.
The findings are published in the journal Plos Biology.