This project is designed to determine if mussels near the northern Ventura County coastal watershed outlets are being impacted by heavy metals discharged in stormwater runoff. This knowledge is critical for people consuming these mussels, as concentrations of heavy metals can accumulate in mussels and other coastal species, and pose health risks to those that ingest them. This project builds on the Northern Ventura County Coastal Watershed Project (NVCCWP) which identified 18 metals that were at or above EPA toxicity screening levels for chronic exposure. Of these 18 metals of concern, 12 have been selected for testing in mussels. If considerable impacts to coastal fisheries from heavy metals are detected it will provide support to enforce upstream erosion control best management practices to mitigate these impacts. Mussels will be sampled before, during, and after storm events to analyze the accumulation and excretion rates of heavy metals in the mussels following storms.

This study will augment the Northern Ventura County Coastal Watersheds Risk Assessment of Transported Metals, which is designed to assess the distribution of metals into the coastal environment from watershed outlets, and will be conducted simultaneously. Pairing these projects enhances each study’s singular value (ultimately providing a greater cumulative value), as data generated through each study will be used to support the other, and strengthen the understanding of the transport and fate of heavy metals along this section of the coast.

Mussels on a rock near Faria Beach County Park. Mussels in this area will be sampled as part of the assessment.