Another Dead Gray Whale Found in Bay Area, Marking the Most in 25 Years

Another gray whale was reported dead near Point Isabel in Richmond on Friday, marking the 19th such death in Bay Area waters this year.

Researchers have not recorded this many gray whale fatalities since 2000, according to the Marine Mammal Center in Sausalito. Comparatively, only nine gray whales were found dead in the region in all of 2024 and 2023. The numbers also surpass those recorded during the “unusual mortality events” in 2019 and 2021, which had 14 and 15 fatalities, respectively.

No further details were available on the whale found Friday morning.

In total, 22 whales have died in the greater San Francisco Bay region since January, according to researchers at the Marine Mammal Center and the California Academy of Sciences.

“We don’t typically see a lot of dead whales inside the bay,” said Sue Pemberton, assistant manager of marine mammal stranding at Cal Academy. “But it could be directly attributed to the fact that there are so many whales here.

“What’s escaping us all is why they’ve decided to use the bay as a snack shack, and how they’re letting their friends know it’s a good place.”

More than 30 individual gray whales have been spotted by Bay Area researchers this year, compared to the six recorded last year. While the waters surrounding the bay are part of the whales’ typical migration pattern from Mexico to Alaska, Pemberton noted that the sheer number of recent sightings is “unprecedented.”

Scientists are unsure as to what could be causing the increase.

Pemberton said it’s possible that the unusual phenomenon could be an adaptation on the part of the migrating animals. The gray whales may have figured out that there are places in the bay that are very lucrative for them to forage and thus will become a more regular part of their migration moving forward, she added.

Either way, there could be a direct correlation between their heightened interest in lingering in the bay and the number of whales dying, she said.

Earlier this month, a male gray whale was found dead near Lands End in San Francisco. More than 11 were discovered the month prior in places such as Berkeley, Bolinas, Southeast Farallon Island and Point Reyes.

While experts have yet to determine a cause of death for many of the whales due to location and state of decay, it is suspected that at least six of the gray whales died as a result of blunt force trauma caused by vessel or boat collisions. One gray whale that died in April, for example, was found with six fractured vertebrae.

Other necropsies have turned up inconclusive results.

Still, Pemberton said it’s different from an unusual mortality event. Despite the high number of recorded gray whale fatalities, the compressed area that the whales are in makes it less concerning, she said.

The San Francisco Bay is relatively small compared to the whales, Pemberton said. It’s also an area with frequent cargo ship and boat traffic, making it particularly dangerous for large aquatic animals. In the case of unusual mortality events, such as the ones in 2019 and 2021, spikes in the mortality rate of whales were seen across a larger geographic area and the causes of death were harder to determine, she added.

As of now, the number of whale sightings has gone down by nearly 50% in the last few days, Pemberton said. It’s likely that many of them are preparing to continue migrating toward Alaska and will be gone in the next few weeks.

She recommends that people operating ships move cautiously until then and report any whale sightings to vessel traffic and ferry operators. People can also call the Marine Mammal Center if they suspect they’ve seen a whale.

“We have a very unique and extraordinary opportunity to see the migration of whales right here off of our coast,” Pemberton said. “People should be mindful. … [The whales] have every right to be here as much as anything else, so we should come from a place of compassion.”