Why do beached whales die so often?

Asked by: Andrew Gill, Christchurch

Cetacean stranding often leads to death due to dehydration. Whales have an incredibly thick layer of insulating blubber. Without the water to keep them cool, they overheat and lose too much water via evaporation from their lungs.

Whales can also drown as the tide comes in because they are lying on their side and the water covers their blowhole before it’s deep enough for them to swim free. Even if they do get back into the water, many whales die a few hours later because their huge weight causes crush injuries that release toxic breakdown products into their blood when the pressure is removed.

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