San Francisco Baykeeper received a tip on its hotline Thursday of a possible algae bloom and sent out a drone Friday that captured footage of a red tide spreading between Albany and Emeryville, said Rosenfield. 

Water samples of the bloom contain a large number of Heterosigma akashiwo cells, the same type of algae that devastated the bay last summer. 

San Francisco Bay’s toxic algae bloom is suddenly back. How bad will it get?

Source: San Francisco Chronicle