Cosumnes River Preserve
The Cosumnes River Preserve is a nature preserve of 46,000 acres (190 km2) located 20 miles (30 km) south of Sacramento, in the US state of California. The preserve protects a Central Valley remnant that once contained one of the largest expanses of oak tree savanna, riparian oak forest and wetland habitat in North America. Agricultural development has changed the landscape from groves of oaks and tule marshes to productive farmlands.The Cosumnes River is the last remaining free-flowing river in California's Central Valley, with the preserve located on the river's lower reach where it joins the Sacramento-San Joaquin Delta tidelands. The area supports a diverse range of plant and animal life, including three species of oak as well as rare plants like the endemic northern California black walnut (Juglans californica var. hindsii). Notable features include the sandhill crane fall migration and the Tall Forest in Wood Duck Slough. More than 250 bird species, more than 40 fish species, and some 230 plant species have been identified here.Located on the bird migration route, the Pacific Flyway, the preserve is designated an Important Bird Area by the American Bird Conservancy and National Audubon Society. Several rare birds, such as the Tri-colored Blackbird and the Greater Sandhill Crane, have been identified. Many bird species that have been extirpated from most of the Central Valley are returning to the area.The preserve is between two growing urban centers, Sacramento in the north, and Stockton to the south, which threaten to constrict the protected areas to a narrow corridor extending from the Sierra foothills to the Sacramento River Delta.The National Park Service has been protecting the area since 1976 when the agency added the Cosumnes River environment to the National Natural Landmark Program as the Cosumnes River Riparian Woodlands. This program conserves examples of the country's natural history and is the only natural areas program of national scope that identifies and recognizes the best representations of biological and geological features in both public and private ownership.