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PILOT whales are the cheetahs of the oceans, hunting juicy prey in short, intense chases. They are the first deep-diving whales known to use such a strategy.

Until now, it had been thought that whales always minimise their oxygen use under water by cruising slowly to graze on slow-moving prey. But when Peter Tyack of Woods Hole Oceanographic Institution in Massachusetts and colleagues attached data recorders to 23 short-finned pilot whales off the Canary Islands, they found something different. Near the bottom of their deep dives, the animals made a sudden sprint of 30 seconds or less, accompanied by a furious burst of echolocation clicks, which usually signals nearby prey. The sprint explains why the dives only last 15 to 20 minutes, when other deep-diving whales spend up to an hour on their hunting expeditions.

The researchers calculated that the sprint accounts for nearly a quarter of the dive’s entire oxygen use during just 3 per cent of its duration – a huge price for a breath-holding animal to pay (Journal of Animal Ecology, ). The effort would need a large potential pay-off, possibly in the form of catching fast-moving, muscular – and hence especially nutritious – squid.