Since the start of 2019, more than 70 dead gray whales have washed up on the coasts of California, Alaska, Washington and Canada. This is one of the most gray whales‘ death in one year since 2000, and scientists are concerned.
Last week, the National Oceanic and Atmospheric Administration or the NOAA Fisheries designated these strandings as a part of an Unusual Mortality Event or UME. Under the U.S Marine Mammal Protection Act, the designation of a UME means that there are more scientific expertise and resources that will be dedicated to investigating the problem about whales dying.
During this time of year, seeing a lot of gray whales swimming along the west coast is expected. From March to June, these marine mammals swim north from the coast of Baja California, Mexico, and Bering, Chukchi seas which are in the north of Alaska. They will start their return trip in November going south.
So far, there are 73 dead whales that have been spotted on West Coast beaches this year, 37 in California, three in Oregon, 25 in Washington, 3 in Alaska and 5 in British Columbia, Canada. Most of them were malnourished and skinny, which suggests they probably did not get enough to eat during their last feeding season in the Arctic, said Micheal Milstein, an NOAA Fisheries public affairs officer.
“Most whales and especially emaciated whales will tend to sink when dead,” said John Calambokidis, a research biologist with Cascadia Research Collective. “So the numbers that wash up represent a fraction of the total. The vast majority go unreported... some estimates suggest it's as few as 10%."
Another theory is that the West Coast gray whale population has overgrown its food source. And due to this year's ocean conditions, it meant that there is not enough shrimp, krill and small fish in some places for them to eat. Once considered endangered, gray whale soared due to an international agreement to end whale hunting in the early 1970s, it is now estimated there are around 27,000 in 2016.
"We know from past data that this population is capable of rebounding from a loss on the order of at least 6,000, perhaps," said David Weller, a research wildlife biologist with the NOAA Southwest Fisheries Science Center. "It's still unclear what's causing so many whales to die. So for now, the priority is to learn as much as possible from the stranded animals," Weller said. "We've got our finger on the pulse and I would say that we want to continue to monitor it closely."
