California Sea Otter Research - What's Killing California Sea Otters?

What kinds of pollutants affect otters?
Many pollutants - from sources such as agricultural runoff, sewage plants, marinas and boat yards - become concentrated in shellfish and other otter prey. Organochlorine chemicals, polychlorinated biphenyls (PCB’s), mercury, and other pollutants can affect otters in many ways. They can damage otters’ nervous systems, affect pregnancy and fetal health, and lower the otters’ immune system defenses against diseases.

Oil pollution is also a major threat to otters. When their fur becomes matted by oil, otters can’t maintain their body heat, and they can die from hypothermia. Oil can also damage otters’ internal organs.

Can these pollutants also affect people?

Yes. If pollutants are making otters sick, it’s likely that humans may be at risk for some of the same health problems. Because otters are near the top of the food chain, they eat many of the same shellfish that humans eat. Since humans share the near-shore environment as otters, the marine mammals serve as a good sentinel species for problems in a healthy ecosystem.