Los Vaqueros Reservoir Fish Advisory Offers Safe-Eating Advice for Six Species

Fish Advisory for Los Vaqueros Reservoir Offers Safe-Eating Advice for Six Species

February 26, 2026

For Immediate Release
Contact: Amy Gilson
(916) 764-0955
Amy.Gilson@oehha.ca.gov

SACRAMENTO – Today, the California Environmental Protection Agency’s Office of Environmental Health Hazard Assessment (OEHHA) issued a new fish consumption advisory for Los Vaqueros Reservoir, located 30 miles east of Oakland, in Contra Costa County. The advisory provides safe-eating advice for black bass species, Mississippi Silverside, Rainbow Trout, Sacramento Sucker, sculpin species and Threadfin Shad.

OEHHA’s Good Catch California program routinely develops fish advisories so Californians can make healthy choices about the fish they catch in water bodies across the state.

“If you eat fish from Los Vaqueros Reservoir, check our new fish advice. It can help you decide which fish to eat and how much,” said fish advisory program manager Dr. Wesley Smith. “We issued guidance for six species to help you choose which fish to eat safely.”

OEHHA developed these recommendations based on the levels of mercury found in fish caught in the lake. Historic mining and coal burning released mercury into the environment, where it can accumulate in fish. Because mercury affects brain development, particularly in developing children and fetuses, OEHHA provides advice tailored to two groups based on sex and age.

For Los Vaqueros Reservoir, OEHHA provides the following safe-eating advice:

Women (18 – 49 years) and children (1 – 17 years)

• Should not eat black bass species.

• May eat the following on a weekly basis:

  • Seven total servings of Rainbow Trout, or
  • Five total servings of Mississippi Silverside or sculpin species, or
  • Two total servings of Threadfin Shad, or
  • One total serving of Sacramento Sucker. Women (50 years and older) and men (18 years and older)

• May eat the following on a weekly basis:

  • Seven total servings of Mississippi Silverside, Rainbow Trout, sculpin species, or
  • Six total servings of Threadfin Shad, or
  • Three total servings of Sacramento Sucker, or
  • One total serving of black bass species. One serving for adults is an eight-ounce fish fillet, measured before cooking, which is roughly the size and thickness of your hand. For small fish species, several individual fish may make up a single eight-ounce serving. Children should eat servings of less than eight ounces. Eating fish in amounts slightly greater than the advisory’s recommendations is not likely to cause health problems if it is done only occasionally, such as eating fish caught during an annual vacation.

A poster with safe-eating advice for Bass Lake is available on OEHHA’s website in both English and Spanish. For fish species found in Bass Lake that are not included in this advisory, OEHHA recommends following its statewide advisory for eating fish from California lakes and reservoirs without site-specific advice.

OEHHA’s fish advisory recommendations are based on the levels of contaminants, such as mercury, that persist in the environment and accumulate in fish. They are independent of any shorter-term advisories to limit fish intake due to freshwater or estuarine harmful algal blooms (HABs), which can produce toxins harmful to humans. Before fishing, check the California HAB Reports Map to see if there are HAB advisories and always practice healthy water habits. In addition, anglers should check with California Department of Fish and Wildlife for the latest fishing regulations.

OEHHA has released more than 150 advisories that provide site-specific, health-based fish consumption advice for many places where people catch and eat fish in California, including lakes, rivers, bays, reservoirs and the California coast. OEHHA’s mission is to protect and enhance the health of Californians and the environment through scientific evaluations that inform, support, and guide regulatory and other actions in the state.

Related Notices

• Los Vaqueros Reservoir

February 26, 2026

Fish Advisory Map

View maps of current statewide and site-specific advisories

Fish, Incident Response, Seafood Safety, and Harmful Algal Bloom Section

Sacramento Office
1001 I Street
Sacramento, CA 95814
Phone: (916) 324-7572
Fish@oehha.ca.gov

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