It is not fully understood how whales deal with these problems, as they too are at risk of their body tissues becoming heavily saturated with harmful levels of nitrogen. If we then surface too quickly, dissolved gas will form bubbles in the body, which expand as pressure drops and can be fatal. Human divers face the same problem with uptake of compressed gas. However, at depths shallower than this point, the pressure will compress gasses like nitrogen, increasing the amount dissolved inside blood and tissues. Once the lungs have collapsed, no more gas from the lungs will enter the blood. Increasing pressure shrinks the air in the lungs and by 200 metres deep, both human and whale lungs will have collapsed. High pressures change the uptake of gas in the body. When diving to such great depths, whales face two challenges: storing enough oxygen to hunt successfully and withstanding the enormous pressure. These studies show that the whales dive far underwater to find the best hunting spots, which are full of deep-sea fish and squid. However, with perseverance and patience, depth-recording tags can be attached to the flank below the dorsal fin to monitor their underwater behaviour. Yet these animals are small compared to something like a sperm whale - so how do they do this?'īeaked whales are difficult to study, mainly because they spend their lives in deep offshore waters and shy away from boats. 'It is not just the occasional deep dive that we see, but repeated deep dives many times a day. 'Beaked whales are amazing animals,' she says. One individual made two extremely long dives of 173 minutes and 222 minutes, which the researchers thought might be reaching the limits of the species' diving capacity.Īll whales rely on coming to the surface of the water to breathe oxygen - so they must hold their breath for remarkably long periods of time.ĭr Sascha Hooker of the University of St Andrews is studying marine mammal diving behaviour. The deepest recorded dive was 2,992 metres and the longest lasted 137 minutes, breaking the record for diving mammals.Įxperts have suggested that this was an unusually deep dive for this species, and a more normal depth is 2,000 metres.Ī more recent 5-year study of nearly 3,700 deep dives by 23 beaked whales found that half of all foraging dives lasted an hour or more and 5% exceeded 77 minutes. A 2014 study, published in PLOS ONE, used satellite-linked tags to follow the dives of eight beaked whales off the southern California coast.
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