Harmful algal blooms (HABs) are extreme biological events that can result in negative impacts to fisheries, coastal ecosystems, economies, and public health via the production of natural toxins. In 2015 and 2016, there was an unprecedented bloom of a single-celled plant called Pseudo-nitzschia in ocean waters, which resulted in elevated levels of the toxin domoic acid. This bloom had significant impact on the Dungeness crab, rock crab, and bivalve shellfish (mussels, clams, oysters) fisheries. The elevated levels of domoic acid in bivalve and crustacean shellfish along the West Coast impacted California fisheries from Santa Barbara to the Oregon Border.

This frequently asked questions (FAQ) document was developed by the California Ocean Science Trust in response to the 2015-16 domoic acid event. The goal of this document is to provide clarity for members of the fishing industry, consumers, non-governmental organizations, state agencies, and the Legislature on California’s current practices (through August 2016) with respect to harmful algal bloom (HAB) monitoring and management, and seafood toxin sampling and testing protocols.