SAN FRANCISCO—San Francisco has decided to postpone the opening of Commercial Dungeness Crab and Commercial Rock Crab Seasons because warm water temperatures are creating a bloom of toxic algae in the bay.
The California Fish and Game Commission voted on Thursday, November 5, to delay the opening scheduled for Sunday, November 15. According to California’s Department of Fish and Wildlife (CDFW), the closure of the commercial rock crab and fishery was also closed as of Friday, November 6, an activity which is generally open year-round.
In a statement to the public on November 6, CDFW Director Charlton H. Bonham, stated: “Crab is an important part of California’s culture and economy, and I did not make this decision lightly, but doing everything we can to limit the risk to public health has to take precedence.”
According to the CDFW, algal blooms are common. “This one is particularly large and persistent. Warmer ocean temperatures due to the El Nino event California is experiencing are likely the cause of the size and persistence of this bloom.”
Algal blooms are known to release domoic acid, a neurotoxin known to accumulate in sardines, anchovies, and shellfish. When ingested, domoic acid causes seizures, coma, cardiac arrest, and death in larger amounts. In smaller amounts, it has been known to cause headache, diarrhea, nausea, loss of short-term memory, and disorientation. The effects of domoic acid affect both marine mammals and humans.
According to the CDFW’s press release, the emergency ban of commercial fishing will be in effect until the California Department of Public Health and Office of Environmental Health Hazard Assessment determines that the algal blooms are no longer a threat to the public.
The Commission says it has been working diligently to test contaminated crabs since early September, with the latest results showing a health risk.