Green algae is seen in the St. Lucie River in Stuart, Fla. Local GOP Rep. Brian Mast is making legislation to deal with the algae problem a focus of his re-election campaign, as his Democratic opponent Lauren Baer criticizes him for doing "too little, too late."
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Dungeness crabs for sale at Fisherman's Wharf in San Francisco. California's Dungeness crab season was shut down in 2015, when record high ocean temperatures and lingering toxic algae blooms raised the domoic acid in shellfish to unsafe levels. A new study links dangerously high levels of the neurotoxin to warmer ocean temperatures, suggesting such closures could become more common in the future.
Officials found the toxin microcystin in the blue-green algae present at Discovery Bay, Calif. For people exposed to the toxin, symptoms include dizziness, rashes, fever, vomiting and in more unusual cases, numbness.