Abalone Die-Off Observed Following Red Tide in Sonoma County

By Department of Fish & Game — September 3, 2011

The Department of Fish and Game (DFG) has confirmed reports of dead red abalone and sea stars inside coves along the coast in Sonoma County. The number of dead and dying abalone is not known, but reports have come from Bodega Bay, Russian Gulch, Fort Ross, Timber Cove and Salt Point State Park, beginning on August 27. DFG biologists and game wardens have collected abalone, mussels and water samples and are continuing to document reports from the public.

According to DFG biologists, these abalone deaths coincided with a local red tide bloom (or phytoplankton bloom) and calm ocean conditions. Although the exact reasons for the abalone deaths are not known, invertebrate die-offs have occurred in the past along the northern California coast when similar weather and bloom conditions existed.

Biologists are not attributing the deaths to Withering Syndrome (an abalone disease), since the abalone are not withered and other invertebrates have been affected. Withering Syndrome has been known to cause abalone mortality in the past in central and Southern California.

The abalone fishery remains open at this time. Abalone divers and pickers are reminded that they must adhere to all licensing requirements and bag limits, which can be found online atwww.dfg.ca.gov/marine/mapregs3.asp#abalone_open. There is a daily limit of three abalone and a yearly limit of 24 abalone, along with season restrictions and area closures as well as other regulations for recreational abalone fishing in northern California.

Abalone fishermen are advised to contact a physician immediately if they feel sick, and to report symptoms to the local county health department (www.sonomacounty.org/health/about/publichealth.asp).

The public is encouraged to report the location, number and date of dead or dying abalone to Ian Taniguchi at (562) 342-7182 or by e-mail at itaniguchi@dfg.ca.gov. The latest red tide updates from the California Department of Public Health are also posted online at www.cdph.ca.gov/programs/Pages/DDWEM.aspx.