After 2022’s Fatal Algal Bloom, Scientists Fear the Bay’s Sturgeon Could Go Extinct
At Point Pinole, 21 sturgeon carcasses––some more than seven feet long––lay strewn along a mile-long stretch of beach in late August 2022, baking in the relentless heat. It was the peak of the largest harmful algal bloom on record in San Francisco Bay, and people noticed.
Around the Bay, members of the public made hundreds of sturgeon carcass reports to government agencies and on the citizen-observation platform iNaturalist—so many that four months later, the California Department of Fish and Wildlife is still sorting through them.
Sturgeon survived the calamity that struck down the dinosaurs, the movement of continents across the ages, and the advent of the Anthropocene, hardly changing over 200 million years. But this summer’s harmful algal bloom, also known as a red tide, triggered the largest sturgeon mortality event ever recorded in the San Francisco Bay estuary.
In November, 12 fisheries scientists wrote an open letter expressing worry that this catastrophic event could push the Bay’s white sturgeon population onto a path toward extinction. The authors of the letter include fisheries and sturgeon scientists from UC Davis, UC Santa Cruz, the National Oceanic and Atmospheric Administration, and Cramer Fish Sciences, a fishery science consultancy. The letter was published on the California Water Blog, a collaborative project based at UC Davis’s Center for Watershed Sciences.
“We’re very alarmed,” says Levi Lewis, a fisheries biologist at UC Davis who cowrote the letter. “Sturgeon are long-lived, very slow-reproducing fish that cannot tolerate high levels of mortality.”