A dead gray whale washed ashore at Francis
© Adam Parde
A dead gray whale washed ashore at Francis State Beach on Tuesday. It was drifting in and out with the tides on Thursday.
A dead gray whale washed ashore on Tuesday evening at Francis State Beach in Half Moon Bay. It had disappeared by Thursday morning, officials say, but much of the remains had drifted back to shore by this afternoon.

The California Academy of Sciences received reports of the whale from California State Park rangers on Tuesday, said Marine Mammal Center spokesman Giancarlo Rulli. By the time an expert from the academy arrived at the beach Thursday morning, the decomposing whale was gone.

Because no necropsy was performed, experts don't know how it died or how old it was. The whale's appearance is the latest in a slew of sightings over the last five months. This was the eighth gray whale to wash ashore in the Bay Area since April 1. An adult female gray whale was found beached at the Fitzgerald Marine Reserve on April 3.

Before this week's discovery in Half Moon Bay, the Marine Mammal Center in Sausalito said its experts responded to nine dead whales throughout the Bay Area this year.

From Tiburon to the Port of Oakland to San Francisco, five dead whales were found in April alone. The cause of most of the deaths are still undetermined, but the Marine Mammal Center suspects ship strikes for at least three of the deaths, which along with malnutrition and entanglement, is the most common cause for whale deaths in the Bay Area. In 2019, the National Oceanic and Atmospheric Administration declared an Unusual Mortality Event for gray whales after an increasing number of them died during their migratory range from Mexico to Alaska.

The Marine Mammal Center collects samples of beached whales and works with the California Academy of Sciences to determine the cause of death in each case. Being able to get a fresh sample is a crucial component of the process, Rulli said

"The public plays a really important role for our teams in these responses in terms of alerting us," said Rulli. "We really stress to the public to report dead whales to our hotline."

To report a dead mammal, or an animal in distress, call the hotline at (415) 289-7325.