The California Department of Fish and Wildlife (CDFW) has shut down the recreational razor clam fishery in Humboldt County after a recommendation from state health agencies. According to these agencies, consuming razor clams in the area poses a significant threat for domoic acid exposure. Pseudo-nitzschia, a naturally occurring, single-celled marine alga, produces the potent neurotoxin domoic acid under certain ocean conditions. Bivalve shellfish, like clams and mussels, accumulate the toxin without being harmed.
In late April 2023, samples of razor clams from Clam Beach in Humboldt County were found to exceed the current federal action level for domoic acid of greater than or equal to 20 parts per million. Domoic acid poisoning in humans may occur within minutes to hours after consumption of affected seafood and can result in signs and symptoms ranging from vomiting and diarrhea to permanent loss of short-term memory (Amnesic Shellfish Poisoning), coma or death. There is no way to prepare clams for consumption that will remove the toxin – cooking and freezing have no effect.
The closure of the recreational razor clam fishery in Del Norte County also remains closed due to elevated levels of domoic acid. The closure began in November 2023 and will remain in effect until state health agencies determine that razor clams no longer pose a health risk. CDFW is working with the California Department of Public Health (CDPH) and Office of Environmental Health Hazard Assessment (OEHHA) to collect, monitor, and analyze razor clams to determine when it is safe for them to be reopened for fishing again.
For more information on any fishery closure or health advisories, please visit www.wildlife.ca.gov/Fishing/Ocean/Health-Advisories . To get the latest information on current fishing season closures related to domoic acid, please call CDFW’s Domoic Acid Fishery Closure Information Line at (831) 649-2883 . For the latest consumption warnings