The remnant sand dunes at Antioch Dunes National Wildlife Refuge provide the only remaining home for for several species including the Lange’s metalmark butterfly, Contra Costa wallflower and Antioch Dunes evening primrose.
During a dry interglacial period some 140,000 years ago, a network a sand dunes extended from the San Joaquin River to the Mojave Desert. Today a remnant of that once-mighty swathe remains in the 71-acre Antioch Dunes National Wildlife Refuge along the southern shore of the San Joaquin River, although the industrial surroundings make for a less-than-picturesque backdrop,
The isolation of this sand dune habitat has resulted in the development ofa unique assemblage of plants, insects, and reptiles. Due to thesensitivity of the habitats and the endangered species, the refuge isnot open to unsupervised use by the public. Refuge staff and local educators conduct on-site environmentaleducation efforts through guided tours and special events.