Center for Biological Diversity


For Immediate Release, November 13, 2015

Contact: Dr. Abel Valdivia, (510) 844-7103, avaldivia@biologicaldiversity.org 

Harmful Algae Blooms Causing Toxic Crabs,
Marine Mammal Mortalities More Likely as Oceans Warm

OAKLAND, Calif.— The ongoing toxic algae bloom along the West Coast — which has shut down crab fisheries in California — is likely poisoning marine mammals from Mexico to Alaska. This is a serious ecological and economic threat, which could get even worse and more frequent in a warmer future as greenhouse gases continue to accumulate in the environment. 

“This is another wake-up call that our oceans are in trouble, need help and need it soon. Waters warmer than usual are becoming more frequent in this region, and studies show these toxic conditions may become common unless we change our ways,” said Dr. Abel Valdivia, a marine scientist with the Center for Biological Diversity. “There’s just too much at stake to ignore this problem and hope it goes away.”

California officials recently cancelled the opening of the Dungeness crab fishery, a profitable, $60 million annual commercial season that was set to begin this Sunday, and closed the rock crab fishery due to high levels of domoic acid from the massive algae blooms that began in the spring of this year. Domoic acid is a powerful neurotoxin that causes serious health problems for both people and marine animals.

Studies show that harmful algae like Pseudo-nitzschia, which produces domoic acid, can be five times more toxic at levels of ocean acidification that are already occurring off the California coast. While crabs can metabolize this toxin, it accumulates in fish and travels up the food chain. Domoic acid poisoning is suspected by the National Oceanic and Atmospheric Administration to have caused sea lion strandings and bird deaths along the West Coast and the deaths of 30 large whales in the Gulf of Alaska.

Prominent ocean researcher Raphael Kudela of the University of California, Santa Cruz last week testified to Congress that the algae bloom could scuttle this crab season and be even worse next year. He has also said such toxic conditions could be “the new normal” as the Northeast Pacific Ocean increasingly warms and absorbs carbon emissions and nutrients from coastal runoff.

“These are the kinds of events that are dramatically altering our oceans in vast and damaging ways, affecting not only marine ecosystems but also coastal economies. We must curb carbon emissions to decrease warming waters,” Valdivia said. “The science is clear; now we, as a human society, just need the political will to act on that knowledge.” 

The Center for Biological Diversity is a national, nonprofit conservation organization with more than 900,000 members and online activists dedicated to the protection of endangered species and wild places.


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