Aquarium aids sea otter comeback

Monterey Bay Aquarium scientists released surrogate-reared otter into Elkhorn Slough.
©Monterey Bay Aquarium

With help from the Monterey Bay Aquarium, threatened southern sea otters have made a comeback in Elkhorn Slough, an estuary in Central California. A recent study looking at how the program has helped restore the population over 15 years shows that sea otters (Enhydra lutris) reared at the aquarium account for more than 50% of population growth. The sea otters had once been hunted to near extinction in California during the fur trade in the 18th and 19th centuries, and the aquarium in collaboration with state and federal authorities wanted to help restore the species. They began conducting a surrogacy program in which non-releasable females raised rescued pups so that they could eventually return to the wild. The research shows the program has been successful since the surrogate reared pups survived and reproduced at rates similar to wild-raised pups. They also found most of the surrogate-raised pups remained in Elkhorn Slough after they were released. The research team thinks releasing surrogate-reared pups into coastal estuaries can help rebuild otter populations elsewhere and restore healthy ecosystem in places like Morro Bay, also along the Central Coast.

Read the study in the journal Oryx.