As dead fish pile up, the economic and environmental impact of the red tide becomes apparent
Thousands of dead fish have washed up on shores across the Bay Area in recent weeks. A red tide is killing everything from anchovies to sharks. Preventing a similar disaster may cost the region billions of dollars. In late July, Mary Spicer noticed that the water lapping around her kayak started to turn red. A few weeks later it was dark brown. … Jon Rosenfield, senior scientist with environmental group SF Baykeeper, says Heterosigma may be killing fish in two ways: It can produce a toxin that is deadly to fish, but it can also result in low dissolved oxygen levels in the water, which can be deadly.