Thursday, May 13, 2010

Just Keep Turning Left

A grey whale ends up in the Mediterranean Sea:
Conventional wisdom has it that grey whales have been extinct in the Atlantic Ocean for more than 200 years, and the species survives only in the north Pacific. That was the case until last weekend, when a 13-metre-long grey whale was spotted cruising off the coast of Israel.

"This is sensational," said Phillip Clapham of the US government's National Marine Mammal Laboratory in Seattle after hearing the news from marine biologists in Israel. "The most plausible explanation is that it came across an ice-free North-West Passage from the Pacific Ocean, and is now wondering where the hell it is."

The North-West Passage, which runs through the Canadian Arctic, has been open in summer in recent years, partly because of rising global temperatures.

Although they are known for their long migrations, grey whales do not normally stray from their regular routes. "Were I to speculate wildly, I'd say it found Europe and remembered its mother telling it to keep the coast to its left going south, then it hit the strait of Gibraltar and entered the Mediterranean," said Clapham.

The Arctic route makes most sense, agrees Giuseppe Notarbartolo di Sciara, an expert on Mediterranean cetaceans who advises several international conservation bodies. He points to reports that grey whales have been seen getting farther north than usual into the Arctic, probably helped by the low-ice conditions.

"Probably this one went so far east that when the time came to go south it had the Atlantic rather than the Pacific in front of its rostrum," says di Sciara. "Then, hugging the eastern side of the ocean as any good Pacific grey whale would do, it went into the first big warmish 'lagoon' it could find: the Mediterranean."

The finding was announced last Saturday by Aviad Scheinin, chairman of the Israel Marine Mammal Research and Assistance Center, who had followed the whale at sea for 2 hours. He at first thought it was a sperm whale, but checked the markings back on land and reached the "incredible but inescapable conclusion that it was a grey whale". Clapham told New Scientist that the identification had now been confirmed.

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