Endangered Blue Whales Returning to Alaska
Endangered blue whales are making a comeback in Alaskan waters after nearly being wiped out by commercial hunters decades ago.
Before they were nearly killed off, blue whales frequently traveled between Mexico and Alaska in search of food during the summer. But since the massive hunting season of 1931, during which more than 29,000 of the species were killed, researchers have found blue whale sightings to be sparse, until recently.
It wasn’t until 2004, when researchers were conducting a survey of humpback whales that they noticed three blue whales in the Gulf of Alaska. They later noticed another three in the Aleutian Islands.
"No one had seen blue whales in these waters since the end of whaling," Jay Barlow, a scientist with the National Oceanic and Atmospheric Administration, told the Associated Press.
Researchers took photographs of the six whales and compared them to images in an identification catalog from the mid-1980s. They noted matched in the pigmentation of the skin and the shape of its dorsal fin.
Scientists also matched one image taken from the Alaskan Gulf to a California whale that had previously been spotted five times in 1995 and 1998 near the Santa Barbara Channel.
Although researchers are unsure as to why the blue whale appears to be expanding its migratory patterns, some suggest that it is traveling further north in search of more krill to feed on. Blue whales have a large appetite for the tiny shrimp-like krill, as they can eat about 4 tons in one summer day.
John Calambokidis, a research biologist at Cascadia Research Collective in Olympia, Wash, who works with NOAA and the Canadian Department of Fisheries and Oceans, told the AP that one or two blue whales were seen in British Columbia in 2005 and 2006.
Then in 2007, five blue whales were seen in one day, including a mother and calf, near the Queen Charlotte Islands off British Columbia. The following day, researchers documented three more.
Eventually, they noted 15 blue whales altogether off the coast of British Columbia and in the Gulf of Alaska. Researchers have concluded that they are part of a California group that consists of about 2,000 whales.
"We speculate that this represents the re-establishment of a traditional migration pattern for an eastern North Pacific blue whale population," researchers wrote.
"When the food dries up, these animals wander over enormous ranges," said Bruce Mate, director of the Marine Mammal Institute at Oregon State University.
"I think what we are looking at now is what has always been," he said.
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