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Global warming: humpback whales threatened by marine heat waves
Scientists have looked at the evolution of the population of humpback whales in the Pacific Ocean, noting the dramatic increase in their mortality. On the 20 Hours set, Nicolas Chateauneuf explains the reasons for this decline.
(France 2)
Scientists have looked at the evolution of the population of humpback whales in the Pacific Ocean, noting the dramatic increase in their mortality. On the 20 Hours set, Nicolas Chateauneuf explains the reasons for this decline.
We have just had the warmest winter on record in the world. The month of February is part of a series of nine consecutive months where the heat record has been broken, according to the European Copernicus observatory. The average ocean temperature also exceeded the previous record for August 2023. This heat has dramatic consequences for humpback whales. Scientists have embarked on the study of these cetaceans, and “have managed to track their precise population in the northern Pacific Ocean”explains Nicolas Chateauneuf on the set of 20 Heures, Thursday March 7.
The number of whales has decreased by 20% in 10 years
The study found that “the number of humpback whales has fallen by 20% in ten years, from 33,000 to 26,000 individuals. While the population had increased for 35 years after the end of industrial hunting“, underlines the journalist. One of the explanations for this phenomenon is marine heat waves. “Since 2014, the northern Pacific has experienced several exceptional heat episodes”again reminds Nicolas Chateauneuf.
And this has several consequences: “whales are losing weight and having fewer babies” because their prey is decreasing, explains Nicolas Chateauneuf, adding that “to avoid areas that are too hot, whales venture into areas more frequented by boats”which increases the risk of injury and collision with boats.
Among our sources:
Royal Society study
Image of the 2015 marine heatwave published in the scientific journal Geophysical Research Letters
Study on the 2015 marine heat wave published in the scientific journal Geophysical Research Letters
Humpback whales victims of marine heat waves – The world
Non-exhaustive list.
