Trail Closure

South San Francisco Bay Shoreline Project (Phase I) between the Alviso Slough/Guadalupe River and Coyote Creek is underway. Mallard Slough Trail is closed due to construction as well as sections of Alviso Slough Trail at Don Edwards San Francisco Bay National Wildlife Refuge in Alviso California. Construction hours are 7 a.m. to 5:30 p.m., Monday through Friday, and on weekends as necessary, excluding holidays. Construction is scheduled to finish in June 2025. For more information. 

In the heart of California's high-tech industry lies a wildlife oasis in an urban sea with 30,000 acres of habitat for millions of migratory birds and endangered species. Established in 1972 through local activism, the refuge provides not only critical habitat for threatened and endangered species, but opportunities for people to enjoy the benefits of nature.

Visit Us


1 Marshlands Rd.

Fremont, CA  94555

Phone:  510-792-0222 

Vehicle entrance gate

7:00 am - 7:00 pm

Fremont Headquarters/Visitor Center

7:00 am - 5:00 pm

Alviso, Environmental Education Center. 


Open sunrise to sunset.

Location and Contact Information

      About Us

      The nation's first urban national wildlife refuge national wildlife refuge
      A national wildlife refuge is typically a contiguous area of land and water managed by the U.S. Fish and Wildlife Service  for the conservation and, where appropriate, restoration of fish, wildlife and plant resources and their habitats for the benefit of present and future generations of Americans.

      Learn more about national wildlife refuge
      sits on the southern end of San Francisco Bay.  It is indeed a wildlife oasis in an urban sea. The refuge, created in 1972, was largely the result of grassroots efforts by the local community to protect the San Francisco Bay ecosystem. Today, it provides not only critical habitat for threatened and endangered species, but opportunities for people to enjoy the benefits of nature.

      What We Do

      Don Edwards San Francisco Bay National Wildlife Refuge was established to preserve and enhance wildlife habitat; protect migratory birds and threatened and endangered species; and provide opportunities for wildlife-oriented recreation and nature study for the surrounding communities.

      Our Species

      Fifteen habitat types exist on the Don Edwards San Francisco Bay National Wildlife Refuge, contributing to the diversity of wildlife on the refuge. More than 340 plant species and 280 species of birds call the refuge home, and millions of individual birds fly through the area during peak migrations. In addition to plants and birds, the refuge provides habitat for fish, mammals, reptiles, amphibians, and invertebrates!

      A small brown bird by the water

      The California clapper rail (Rallus longirostris obsoletus) is one of the largest rails (family Rallidae), measuring 13-19 inches from bill to tail. It is characterized by its hen-like appearance, a long, slightly downward-curving bill, olive-brown upper parts, a cinnamon-buff colored breast,...

      FWS Focus
      A face-shot of California tiger salamander on top of green groundcover

      California tiger salamander is a large, stocky, terrestrial salamander with a broad, rounded snout. Adults males are about 8 inches long, females a little less than 7 inches. Coloration consists of a black back and sides with white or pale yellow spots or bars. The belly varies from almost...

      FWS Focus
      Western snowy plover

      The western snowy plover is a small shorebird with moderately long legs and a short neck. Their back is pale tan while their underparts are white, and have dark patches on the sides of their neck which reach around onto the top of their chest. Juveniles are similar to nonbreeding adults, but...

      FWS Focus

      Get Involved

      Whether you want to further conservation, learn more about nature or share your love of the outdoors, you’ve come to the right place. National wildlife refuges provide many opportunities for you to help your community by doing what you love. National wildlife refuges partner with volunteers, youth groups, landowners, neighbors and residents of urban communities to make a lasting difference. Find out how you can help make American lands healthier and communities stronger while doing something personally satisfying.