Timeline: 2007-2008
Client/Partner: Department of Pathology, Microbiology and Immunology, School of Veterinary Medicine, University of California, Davis.
Study Location: Rivers and Estuaries along Monterey Bay
Role: Lab Manager

Background:

The central California coast has an especially rich tourism industry, attracted by the diverse estuarine and marine resources of the region, including extensive sandy beaches and scenic, rocky coastlines. In addition, this area offers ample opportunity for water-contact sports such as swimming, surfing, kayaking, and wildlife viewing. Fisheries also exist locally for the harvest of marine-origin foods for human consumption including shellfish, crustaceans, squid, fish, and kelp products. Fecal pollution by terrestrial-origin bacteria and parasites is significantly impairing coastal beneficial uses throughout California by causing beach closures and human disease. Between 2000 and 2002, the number of days of beach closure for Santa Cruz and Monterey County almost tripled, from 3.9 to 11.8 beach-mile days. This finding is substantiated by recent CCLEAN data indicating that most coastal streams between the San Lorenzo River and Salinas River have exceeded the proposed Basin Plan Amendment for concentrations of E. coli (CCLEAN, 2005).

Fecal-origin biologic pollutants also appear to be negatively impacting the health of the southern sea otter. As a federally protected threatened species, the survival and maintenance of sea otters must be supported by the quality of California coastal waters. Despite decades of protection, the southern sea otter population has demonstrated an alarmingly slow rate of recovery. Elevated mortality due to infectious disease, including disease associated with terrestrial-origin protozoa and bacteria appears to be a main factor limiting southern sea otter recovery (Kreuder et al., 2003; Thomas and Cole, 1996). Several pathogens isolated from dead and dying sea otters appear to have anthropogenic origins and could be associated with coastal development, wetlands ablation, and coastal wastewater discharge (Conrad et al., 2005; Miller et al., 2002, 2005c, 2006). Many of these sea otter pathogens are similar or identical to fecal pathogens that cause illness in humans. Collectively these data indicate significant impairment to the water contact recreation beneficial use and sea otters along the central California coast, though contributing sources and sustainable solutions to mitigate fecal pollution are not well understood. The recipients of the benefits from this project are all users of streams, rivers and near-shore marine waters that are impaired by fecal pathogens. The information provided by this project is especially useful to resource managers for guiding implementation actions needed to reduce loads of fecal pathogens. As part of the environmental monitoring component, this project measured indicator bacteria and fecal pathogens in streams, sewage, and mussels to determine which watersheds and times of the year contribute the most to loadings of fecal pathogens and how the incidence of fecal pathogens corresponds to the concentrations of indicator bacteria.

Dr. Alexander Schriewer was responsible for all processes with regards to the laboratory analysis of microbial source tracking markers, compilation and submission of results, and QA/QC. Moreover he compiled the complete data and wrote a peer-reviewed journal publication.

Publication:

Schriewer A., Miller W.A., Byrne B.A., Miller M.A., Conrad P.A., Hardin D., Yang H-H, Oates S., Chouicha N., Melli A., Jessup D., Wuertz S. (2010). Bacteroidales as a predictor of pathogens in surface waters of the central California coast. Applied and Environmental Microbiology, 76(17), 5802-5814.