Six dead gray whales found in San Francisco Bay area in the last week
Six dead gray whales have been found in the area of San Francisco Bay over the last week, officials said Wednesday, in a year when there has been an unusually high number of sightings in the area.
The gray whales were found dead from May 21 to Wednesday, when one was found washed ashore at Point Reyes National Seashore, the California Academy of Sciences said.
On Monday, two were found the same day — one on Alcatraz and one at Point Bonita, it said.
In most of the cases, no necropsy, which is like an autopsy for an animal, was performed. The partial necropsy for a yearling gray whale found at Bolinas was inconclusive, and results from the necropsy on the whale found Wednesday are pending, the academy said.
The whales have died as an unusually large number of them have been spotted in San Francisco Bay, officials said.
Why the whales died was not clear.
“That is the open question, the why,” Giancarlo Rulli, a spokesperson for the Marine Mammal Center in Sausalito, told NBC Bay Area this week.
“Why not only are there so many deceased whales in the region, but why has it been a banner year of having more sightings in San Francisco Bay of live whales than we have seen in at least two-plus decades, if ever?”
So far this year 14 gray whales and a minke whale have died in the greater San Francisco Bay Area, the academy said, and the deaths of three of them were found to be from boat strikes.
More gray whales have been sighted in the bay this year compared with last, it said — 33, compared with only six in 2024.
Some have looked normal and others emaciated, it said.
“The reason or potential reasons behind the massive spike in sightings this year are still being investigated by researchers,” the academy said. “It is expected that gray whales will be in the bay for another one to two weeks before continuing their annual northern migration to arctic feeding grounds.”
Gray whales used to be common in waters throughout the Northern Hemisphere but are now regularly found only in the North Pacific Ocean, according to the National Marine Fisheries Service, part of the National Oceanic and Atmospheric Administration. They travel around 10,000 miles in an annual round-trip migration, it said.
Gray whales are known to be curious around boats, which means they are often seen on whale-watching trips, the agency said. They can grow to around 49 feet long and weigh about 90,000 pounds.
Because of the long migration, the whales are sometimes hit by vessels and entangled in fishing gear, which are among their top threats, the fisheries service says.