The Sea Otter's Role in the Ecosystem

Sea otters are the textbook example of a "keystone" carnivore. Sea otters dramatically change the structure and complexity of their ecological community. Sea otters increase diversity and productivity.

By consuming 'grazers,' the animals that feed on kelp, the sea otter enhances kelp production.

California kelp forests are the most diverse ecosystem of the temperate latitudes on earth.

California kelp forests have some of the highest primary productivity rates (conversion of sunlight to living material) of any naturally occurring ecosystem on earth.

Sea otters do not cause the local extinction of species. Abalone numbers are often high within the sea otters range. However, the abalones are restricted to deep crevices, out of reach of otter and human harvesters. It is a widely accepted ecological concept that the more diverse and complex an ecosystem, the more stable it is.

Sea otters are an indicator of the health of the nearshore marine ecosystem. An indicator species is an organism that is relatively sedentary and tends to bio-magnify and/or be  sensitive to contaminants.

The sea otter tends to be relatively sedentary in comparison to other marine mammals.

The sea otter eats a wide variety of foods.

The sea otter eats large amounts of food - 25 to 35-percent of body weight per day.

The sea otter is closely related to mink, a carnivore with established sensitivities to contaminants.

Incidence of disease in sea otters is correlated with the contaminants tributyltin (used as an anti-fouling agent in boat paint) and DDT (a banned pesticide). High levels of other contaminants, such as PCB, are also found in sea otter tissues.

The sea otter is an umbrella species. Protections given to the otter tend to 'shelter' and offer benefits to other species, habitats, and ecosystems.

Sea otters have the notoriety of an 'Endangered Species'.

Sea otters have broad appeal to a worldwide audience.

Sea otters have proven to be an effective tool in enacting ecosystem wide protections including:

• Moving large vessel traffic further offshore.
  
  
• Limiting offshore oil development.
  
  
• Creation of protected areas (Monterey Bay National Marine Sanctuary).