![]() Still, determining the exact factors that caused this eradication remains the basic challenge.Īnswering this question will be crucial to conservation efforts in Europe should the species return, according to van den Hurk. By the 16th century, various whaling cultures were active across Europe, leading van den Hurk to suspect they contributed to the whales’ extinction. Researchers do know that the population of Atlantic grey whales began to decline gradually approximately 50 000 years ago – a process that the experts suspect was driven by environmental factors. ‘It’s unclear what triggered their disappearance from the Atlantic - whether it’s an environmental factor, a human factor or a combination of both,’ van den Hurk said. Grey whales have one of the longest known migrations of any mammal, leaving their Arctic feeding grounds in September-October and swimming south as much as around 10 000 kilometres along the coastline to breed in the warm waters off Mexico. Located in the North Pacific, the population of grey whales totalled around 27 000 in 2016, according to the U.S. The grey whale is the only whale species that has completely disappeared from an entire ocean. The resulting “mud plumes” are important to the ecosystem because they churn up nutrients and crustaceans that enrich other sea life. Grey whales suck food from the sea floor while swimming and rolling on their sides, a practice known as bottom-feeding uncommon for other baleen whales. All baleen whales eat by filtering plankton, krill and small fish out of the seawater. They are part of a class of whales whose mouths feature comblike plates of bone known as baleen rather than teeth. Their lifespan is generally 50 to 70 years. Grey whales can grow to as many as 15 metres long and weigh up to 40 tonnes – equal to the combined weight of about 20 cars. That’s why DAG is also assessing the causes of the grey whale’s eradication in the eastern Atlantic five centuries ago, seeking information on factors that might lead to a return of the coastal cetaceans. Van den Hurk is part of the Horizon-funded Demise of the Atlantic Grey whale project (DAG), which is looking into whether the species might eventually return to European waters.Ī better view of the future, of course, requires a clearer understanding of the past. ‘The grey whale is the only whale species that has completely disappeared from an entire ocean,’ he said. The grey whale disappeared from the eastern Atlantic in the 15th century and from the western Atlantic around the 17th to 18th century, according to van den Hurk.Ī research fellow at the Norwegian University of Science and Technology (NTNU), van den Hurk is part of a project inspired in part by several sightings in the Atlantic Ocean over the past decade of individual grey whales from the North Pacific population. Youri van den Hurk is preparing for a possible big welcome-home event - the return of the grey whale to European waters after an absence of about 500 years.
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