Matt Mattison, Founder of Norcal Underwater Hunters and avid abalone diver, has sent out an emergency notice, asking all Sonoma coast abalone divers to temporarily refrain from harvesting any abalone.

Matt Mattison, NorCal Underwater Hunters

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. The August red tide, a natural occurrence caused by an upswell of nutrient-rich cold water, is said to have been the worst in three decades. One diver reports seeing “hundreds and hundreds of out-of-the shell abalone out on the rocks,” unlike anything he’d ever seen.

Matt requests, “If you are going to dive for abalone, please do your hunting on the Mendocino coast which was not affected by this die off. By doing this, it will give a break to the (Sonoma coast) fishery until there can be a count and survey of how servere the die off is. I know we are all in shock and our concerned about the current situation, and we all want a healthy fishery lets be proactive and do what we can to limit the impact to the Sonoma coast fishery for a while.”

Abalone fishermen are advised to contact a physician immediately if they feel sick, and to report symptoms to the local county health department.

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 The latest red tide updates from the California Department of Public Health are also posted online at

For additional information, contact Matt Mattison here, or visit the Department of Fish & Game website by clicking here. If you have any photos to share of the abalone die off, please send them to us at so we can share them with the dive community.

More news and a photos on the abalone die off:
Press Democrat newspaper can be found here.
NBC Bay Area News – click here.
Placer Herald/Rocklin News click here.
AnewsCafe story here.

Stillwater Cove in Sonoma County – a popular abalone diving destination for North coast divers.


For more photos and an update, click here.