Two more gray whales were found dead this week in Alaska amid the mysterious surge of deaths within the species this year along the US West Coast. That makes seven in Alaska and at least 75 total, in what the National Oceanic and Atmospheric Administration calls an "unusual mortality event".
Ocean scientists are were worried about the death rate, the highest in almost two decades. Some of the mammals were underweight, which may mean they could not find enough food in the water, a possible result of climate change, NOAA spokesman Michael Milstein said.
In all of last year, 45 gray whales were found onshore, NOAA said.
Gray whales do most of their eating during summers in the Arctic and migrate to spend half the year in Mexico.
The increase matches what officials have observed in Mexico and along the U.S. The Department of Fisheries and Oceans says six whales have turned up dead in B.C. waters already this year compared with about two deaths annually over the past five years.
Fisheries and Oceans says the strandings began Jan. 1 and continue to date as the whales migrate north to their summer feeding grounds in the Bering, Beaufort and Chukchi seas.
As of May 20, there had been 60 deaths in the U.S. and about 73 in Mexico, in addition to the ones in Canada, the agency said. Last month, the U.S. National Oceanic and Atmospheric Administration has launched a scientific investigation into its cause.
The U.S. agency said the deaths along the coasts of California, Oregon, Washington and Alaska were “the most since 2000 when more than 100 whales stranded throughout the year.” The investigation at that time was unable to identify a specific cause, the agency said.
Canadian officials are working closely with their counterparts in the U.S. and Mexico to investigate the deaths.
The latest in B.C. was discovered Tuesday night off Boundary Bay. Canada’s marine mammal response team and the Canadian Coast Guard moved the 13.8-metre adult female to a coast guard base at Sea Island, where a necropsy was performed Thursday.
He said preliminary observations indicated that the whale’s body condition was better than the previous five whales found dead in B.C. waters — three stranded in Haida Gwaii, one near Victoria and one on the west coast of Vancouver Island.
“The other five were all quite compromised and emaciated,” he said. The whale found at Boundary Bay, however, had a a higher fat content in the blubber, although Cottrell cautioned that more testing is required.
He added that it’s too soon to know what’s causing the deaths.
“Typically, it’s 10 to 15 per cent of animals show that they’re on the skinny side and this year it was 50 to 55 per cent.
“So the indications were [there] early with this migration that there were a number of animals that weren’t showing great body condition and those are the animals likely that are falling out of the population as they migrate north.”
The necropsies are crucial to determine if there are other factors at work — including vessel strikes, entanglements with fishing gear or pathogens — and to identify potential threats to the rest of the population.
That’s where the public can be of invaluable assistance, Cottrell said.
“Our B.C. marine-mammal response program is really dependent on the eyes and ears of the public that are out on the water, that are walking beaches, that see these dead animals or see injured distressed or entangled animals to call us immediately,” he said.
Canada’s marine-mammal incident reporting hotline, at 1-800-465-4336, is monitored 24 hours a day and ensures that investigators can get to a whale as soon as possible.
In the case of a dead whale, a swift response is crucial because fresh tissue and organ samples can provide better information.
In the case of a stranded live whale, a quick response might save its life.
“An example is the live stranded grey whales that we had in Boundary Bay,” Cottrell said, referring to an incident last month. “We received that information immediately and we were able to get out on the same low tide and then help those animals get back out … into deep water and save those two animals.”
Although listed as a species of special concern under Canada’s Species at Risk Act, eastern North Pacific grey whales have being doing well of late. The U.S. National Oceanic and Atmospheric Administration says the population has recovered since the whaling era and has grown to about 27,000.
Meanwhile on the East coast, beloved Wright Whale known as Wolverine, was found dead last week in the Gulf of St. Lawrence.
The nine-year-old whale, named Wolverine, is the first right whale death reported in 2019 after no deaths were reported in Canadian waters last year.
Wolverine was towed to shore on Miscou Island, where more than 20 people from the scientific community sliced began to collect tissue samples and gather measurements to help determine the cause of death.
Scientists won't know the results of the necropsy until months from now, however.
At the same time there is a wright floating in the St. Lawrence River to which authorities are trying to deal with.
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