Open Access
Vet. Res.
Volume 41, Number 1, January-February 2010
Number of page(s) 13
Published online 02 September 2009
How to cite this article Vet. Res. (2010) 41:01
How to cite this article: Vet. Res. (2010) 41:01
DOI: 10.1051/vetres/2009049

Enteric bacterial pathogen detection in southern sea otters (Enhydra lutris nereis) is associated with coastal urbanization and freshwater runoff

Melissa A. Miller1, Barbara A. Byrne2, 3, Spencer S. Jang3, Erin M. Dodd1, Elene Dorfmeier1, Michael D. Harris1, Jack Ames1, David Paradies4, Karen Worcester5, David A. Jessup1 and Woutrina A. Miller2

1  California Department of Fish and Game, Marine Wildlife Veterinary Care and Research Center, 1451 Shaffer Road, Santa Cruz, CA, 95060, USA
2  Department of Pathology, Microbiology and Immunology, School of Veterinary Medicine, University of California, Davis, CA, 95616, USA
3  Microbiology Laboratory, Veterinary Medical Teaching Hospital, University of California, Davis, CA, 95616, USA
4  Bay Foundation of Morro Bay, 601 Embarcadero, Suite 11, Morro Bay, CA, 93442, USA
5  Central Coast Regional Water Quality Control Board, 81 Higuera St., Suite 200, San Luis Obispo, CA, 93401, USA

Received 23 November 2008; accepted 31 August 2009; published online 2 September 2009

Abstract - Although protected for nearly a century, California's sea otters have been slow to recover, in part due to exposure to fecally-associated protozoal pathogens like Toxoplasma gondii and Sarcocystis neurona. However, potential impacts from exposure to fecal bacteria have not been systematically explored. Using selective media, we examined feces from live and dead sea otters from California for specific enteric bacterial pathogens (Campylobacter, Salmonella, Clostridium perfringens, C. difficile and Escherichia coli O157:H7), and pathogens endemic to the marine environment (Vibrio cholerae, V. parahaemolyticus and Plesiomonas shigelloides). We evaluated statistical associations between detection of these pathogens in otter feces and demographic or environmental risk factors for otter exposure, and found that dead otters were more likely to test positive for C. perfringens, Campylobacter and V. parahaemolyticus than were live otters. Otters from more urbanized coastlines and areas with high freshwater runoff (near outflows of rivers or streams) were more likely to test positive for one or more of these bacterial pathogens. Other risk factors for bacterial detection in otters included male gender and fecal samples collected during the rainy season when surface runoff is maximal. Similar risk factors were reported in prior studies of pathogen exposure for California otters and their invertebrate prey, suggesting that land-sea transfer and/or facilitation of pathogen survival in degraded coastal marine habitat may be impacting sea otter recovery. Because otters and humans share many of the same foods, our findings may also have implications for human health.

Key words: Campylobacter / Clostridium / sea otter / Salmonella / Vibrio

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© INRA, EDP Sciences 2009