Since May 2015, 14 fin whales, 11 humpback whales, one gray whale and four unidentified specimens have been found dead along shorelines in the Gulf of Alaska, nearly half of them in the Kodiak Archipelago. Other dead whales have been reported off the coast of British Columbia, including four humpbacks and one sperm whale.
This year’s total is roughly three times the annual average for the region, leading the National Oceanic and Atmospheric Administration to declare the deaths an “unusual mortality event.” The investigation into the deaths will take months, or even years, according to a statement released by the agency.
Predation, starvation, or disease could be behind the deaths, but researchers say there have been few signs of physical trauma to the whales. The more likely culprit is unusual water conditions.
Over the past two years, a large mass of warm water that climatologists have dubbed “the blob” has persisted in the north Pacific, and El Niño 2015 is pushing more warm water into the region.
The unusually warm and calm seas are believed to be behind a series of toxin-producing algae blooms – record-breaking in size and duration – stretching from southern California to the Aleutian Islands. Clams sampled near the town of Sand Point, Alaska were found to have toxin levels more than 80 times what the FDA says is safe for human consumption, said Bruce Wright, a scientist who studies toxic algal blooms for the Aleutian and Pribilof Islands Association. The levels were ten times anything Wright had previously recorded.