Western Pond Turtles Being Reintroduced to Southern Marin Park Sites

Western pond turtles being raised at the San Francisco Zoo will be reintroduced at Muir Beach and Rodeo Lagoon.

Jessie Bushell / San Francisco Zoo

November 2016 - The National Park Service has entered into a cooperative partnership with the San Francisco Zoo and Sonoma State University to reintroduce the western pond turtle (Actinemys marmorata) to Muir Beach and to sites in the Rodeo Lagoon watershed where it once lived. Western pond turtle populations have declined dramatically throughout the State of California in recent decades, including in Marin County. The species was last seen at Muir Beach in the 1990s.

The reintroduction effort will use eggs collected from donor sites in the Golden Gate National Recreation Area's north district lands, which are managed by Point Reyes National Seashore. They will join seven juvenile turtles already at the zoo—five from eggs from a female killed on a road in southern Marin and two from eggs salvaged from a predated nest at a donor site in Tomales Bay. The hatchling turtles will be reared for one to two years at the zoo before being released.

The effort to locate these donor sites led to the first comprehensive survey for western pond turtles in Point Reyes and Golden Gate’s north district lands. Concurrent research by Sonoma State University will help us learn more about western pond turtle nesting behavior in a coastal environment. Long-term monitoring at the release sites will also provide critical information on survivorship and management needs for this species in a semi-urban environment.

Contact Golden Gate National Recreation Area Aquatic Ecologist Darren Fong to learn more about this project.