SAN FRANCISCO, May 23 (Xinhua). The US National Oceanic and Atmospheric Administration and local authorities were working to tow a dead gray whale that washed up on the shores of Pacifica State Beach in northern California.

Officials at the Marine Mammal Center in Sausalito said they received the report of a dead whale on Pacifica State Beach Friday afternoon. According to authorities, it was the 12th dead whale to wash up on a beach in the San Francisco Bay Area this year.

The California Academy of Sciences collected tissue samples Saturday and confirmed the whale was an adult male approximately 30 meters tall. The cause of death is unknown, according to a report in the San Francisco Chronicle on Sunday.

So far in 2021, 10 gray whales, one pygmy sperm whale and one fin whale have been reported dead on the shores of the San Francisco Bay Area, according to the California Academy of Sciences.

Necropsies revealed that two died in a ship strike and two others were suspected of having died in a ship strike. Eight of the deaths were from unspecified causes, the San Francisco Chronicle reported.