A team from The Marine Mammal Center completes a necropsy on a gray whale stranded at Angel Island State Park, California, May 12, 2019. Photo by Cara Field/©The Marine Mammal Center under NOAA Fisheries Marine Mammal Health and Stranding Response Program permit 18786-03.
By: Holly Eberhard, Legal and Policy Intern
As of June 13th, nineteen gray whales have washed up dead along Bay Area shores this year, including at West Marin locations such as Point Reyes National Seashore, Bolinas, and Rodeo Beach.
This year’s alarming death toll represents a sharp spike within an already troubling long-term trend. Although researchers have not recorded this level of gray whale mortality in the Bay Area since 2000, elevated losses have been observed range-wide in recent years. From 2018 to 2023, the National Oceanic and Atmospheric Administration (NOAA) declared an Unusual Mortality Event for the species, during which the population declined by an estimated 40%.
It remains unclear whether this year’s local spike is directly connected to the broader population decline. However, an unusually high number of gray whales have entered and remained in San Francisco Bay, diverging from their typical migratory path along the outer coast. According to Sue Pemberton, assistant manager of marine mammal stranding at the California Academy of Sciences, this increased presence in the Bay may be contributing to the surge in deaths, as the region’s confined and vessel-heavy waters pose serious risks. Necropsies have confirmed that at least six of the whales died from blunt force trauma consistent with ship strikes.
One possible explanation for this shift in behavior is a search for food. The northern Bering and Chukchi seas—critical gray whale summer feeding grounds—have experienced severe ecological disruption due to sea ice loss and ocean warming, leading to nutritional stress and food scarcity. Although the population experienced a modest uptick in 2024, this year’s strandings suggest that significant ecosystem stressors may still be at play, prompting gray whales to come further into the nutrient-rich waters of the Bay.
This concerning trend highlights the need to protect marine ecosystems and mitigate human-caused threats to ocean wildlife. At EAC, we are committed to safeguarding biodiversity and advancing ocean conservation. We continue to be dedicated to advocating for science-based coastal policies, supporting marine protected areas, and partnering with local and state organizations to promote stewardship along the West Marin coastline and beyond.
