The paper, published in the journal Science Advances, suggests that the industrial hunting of great whales such as sperm, blue, fin and right whales “masked” the ability of these underwater giants to live to great ages.
It has been known since the 1990s that Arctic bowhead whales, with their slow metabolism enabled by cold waters and plentiful food, can reach 200 years old or more.
The scientists achieved their new findings by analysing the lifespans of two similar species: the southern right whale – found below the equator – and the North Atlantic right whale, once plentiful off north European shores but now almost entirely confined to the eastern coast of the US. They discovered that up to 10% of the thriving southern species live past 130 years. Of the much-hunted northern species, only 10% lived beyond 47 years. The conclusion is clear: left alone, whales can live to be very old.
The population of the North Atlantic right whale, a close relative of the bowhead, is now so diminished after the intensive culls of the past, when it was the “right” whale to hunt due to its thick layer of oil-rich blubber, that it is beyond recovery. According to Massachusetts’ Center for Coastal Studies (CCS), which has carried out one of the longest-running studies of the critically endangered population, there are only 372 individuals left.
Declining genetic strength, ship strikes, entanglement in fishing gear, the effects of climate change and sound pollution have weakened them to the extent that they have now been declared “functionally extinct” in the eastern Atlantic, while the west Atlantic population is “not recovering”.