San Francisco August 2022 Deadly Plankton Bloom

Bay Nature cover article 2022

excerpt below

“At times this summer, the shores of San Francisco Bay looked like a piscine battlefront — strewn with dead white and green sturgeon, leopard sharks, striped bass, bat rays, smelt, anchovies, and other fish. It started in late July in Alameda and expanded throughout the entire Bay. By late August, some 10,000 fish had reportedly died at Oakland’s Lake Merritt alone. Where the killer algae bloomed, the water was dull and rust-colored. One resident was quoted saying “the end was near”. A local scientist called the event a “wildfire in the water”. The murk came from the sheer density of the culprit, which was multiplying in the millions: a miniscule organism called Heterosigma akashiwo — akashiwo means “red tide” in Japanese. This wasn’t H. akashiwo’s first star turn. 

H. akashiwo had caused huge, awful blooms in Japan (where it was first described in 1967) and in the Pacific Northwest, where in the mid-1990s and 2000s it killed so many farmed and wild fish that each bloom cost some $2 million to $6 million. Here in the Bay, it had been a relatively chill regular in the phytoplankton crew for years without acting out, showing up in 65 percent of the regular water samples in the central Bay. In California, it wasn’t even considered harmful enough to really worry about, because it wasn’t making toxins that would bioaccumulate in the food chain. But now that H. akashiwo has managed to cause the biggest harmful algal bloom in the Bay’s history, scientists are scrambling to learn more.”

Read the whole article online. SWS Sound Toxins team says it is a very good explanation of harmful algal blooms (HAB).

Recent Articles