Antioch Dunes National Wildlife Refuge

The Antioch Dunes National Wildlife Refuge is located in the San Francisco Bay-Delta area, along the southern shore of the San Joaquin River. It was the first national wildlife refuge in the country established to protect endangered plants and insects.

Established in 1980, the refuge provides protection for three endangered species: Lange's Metalmark butterfly, Antioch Dunes evening primrose and Contra Costa wallflower. The refuge and a few acres of surrounding lands contain most of the remaining habitat for these three species and are all that remain of a nine kilometer stretch of sand dunes formed during glaciation periods.

Isolation of this sand dune habitat resulted in the development of a unique assemblage of plants, insects, and reptiles. Due to the sensitivity of the habitats and the endangered species, the refuge is not open to unsupervised use by the public.

However, refuge staff and local educators conduct on-site environmental education efforts through guided tours and special events. In addition, volunteers regularly assist refuge staff with habitat restoration projects and endangered species surveys.

Getting There . . .

NOTE: The refuge is closed to the public.

Take Highway 4 and exit A Street / Lone Tree Way. Turn North onto A Street. Turn right (East) onto Wilbur Avenue. Turn left (North) onto Fulton Shipyard Road. Cross over the railroad tracks and turn right into the second gravel driveway. The refuge is on your right.

The address is 501 Fulton Shipyard Road, Antioch, CA 94509.

Contra Costa County, CA  
E-mail: sfbaynwrc@fws.gov
Phone Number: 510-521-9624

Wildlife and Habitat

Located along the south shore of the San Joaquin River, the area that is now Antioch Dunes Refuge was part of an expanse of 100-foot-high sand dunes left along the River after the Mohave desert receded in prehistoric times.

Isolation of this sand dune habitat resulted in the development of subspecies of plants and insects that are found nowhere else in the world.

Around the early 1900s, this biological "island" began to experience a dramatic change as human development expanded. The easily-accessible sand was harvested to make bricks, with many of the bricks going to rebuild San Francisco after the 1906 earthquake. Large-scale sand mining and industrial development combined to fragment the sand dune habitat so that only a small portion of the original ecosystem was left. Exotic grasses and vegetation encroached on the sand dunes to crowd the few remaining endangered plants.

By the time the refuge was established, only a few acres of remnant dune habitat supported the last natural populations of Antioch Dunes evening-primrose, Contra Costa wallflower, and Lange's metalmark butterfly. The refuge was open for public use until 1986 when it was closed to protect the plants from trampling and wildfire.

The refuge consists of two units that are managed to prevent the extinction of these unique species. Intensive management has already resulted in the highest Lange's metalmark butterfly population in 20 years. Other species, including the silvery legless lizard have fared well under current protection provided by the refuge.

Environmental Education

Although the refuge is closed to the general public, docent-led tours are offered on the second Saturday of each month at 10 am.

Educational tours are available upon request.

Management Activities

Management of habitat for the Antioch Dunes evening primrose, the Contra Costa wallflower, and the host plant for the Lange's metalmark butterfly is labor intensive. In areas where sand was mined down to the clay substrate, the refuge has imported and reconstructed sand dunes.

Seeds collected from the plants are grown in a nursery for replanting on the refuge. A combination of prescribed burning, mowing, dune reconstruction, hand-weeding, and herbicides are being employed to remove exotic vegetation and improve the substrate for native seedling establishment.

Surveys of all three species, plus other species of special concern, are conducted annually. Applied management research is being conducted in order to develop a comprehensive plan for managing sand dune habitat on the refuge over time.

Fence maintenance and law enforcement are conducted to protect the resources from disturbance and uncontrolled fires.