Why are so many whales dying in San Francisco Bay?

Five whales, including four gray whales and a minke whale, have died in San Francisco Bay over the past month, prompting investigations by the Marine Mammal Center and the California Academy of Sciences. Necropsies revealed that one whale likely died from a vessel strike, while the causes of death for the others remain undetermined. This troubling trend occurs as gray whale populations are still recovering from an unusual mortality event that resulted in 690 strandings along the Pacific coast between 2018 and 2023. Giancarlo Rulli of the Marine Mammal Center noted that gray whales serve as a vital indicator of ocean health, highlighting the need for continued monitoring. The number of whale sightings has significantly increased this year, with around ten sightings reported daily, suggesting a shift in migratory patterns.

Local scientists and citizens have enhanced communication and collaboration, aided by the Harbor Safety Committee. The Center for Biological Diversity stresses the urgency of regulatory measures to mitigate threats from vessel strikes and fishing gear, as about 20,000 whales die globally each year from these causes. Advocacy efforts are ongoing, with calls for more protective actions to safeguard marine species in the bay.