Crestridge Ecological Reserve


The Reserve

Crestridge Ecological Reserve is a 3000 acre parcel of land between El Cajon and Alpine. Jointly managed by the Endangered Habitats Conservancy and the California Department of Fish and Game, the Reserve is bordered by Interstate 8 on the north and west and the community of Crest on the south and east. This beautiful piece of nature preserves the area’s rich prehistory and history, representing thousands of years of human use of the project site. Crestridge also includes areas that have been altered from their native condition by human use; primarily agriculture and motorized vehicle recreation. Ongoing efforts are in place to assess the impact of these disturbances on the native ecosystem. Under contract, the Earth Discovery Institute is overseeing the implementation of the Crestridge Habitat Management and Monitoring Plan.

Biological Resources

The Crestridge Ecological Reserve is a nearly 2,400-acre Ecological Reserve as designated by the California Fish and Game Commission and a unit of the Multiple Species Conservation Program (MSCP) in San Diego County. The property is subject to a Conservation Bank Agreement with the California Department of Fish and Game (CDFG) and The Nature Conservancy (TNC). Designation as a reserve has protected Crestridge from the threat of development.

The goals of the MSCP are consistent with the goals of an Ecological Reserve. The MSCP provides special protection for the irreplaceable resources in San Diego County and guides development outside of biological resource core areas. Protection of these irreplaceable resources is vital to the general welfare of all residents. Central to the MSCP is the maintenance of ecosystems and vegetation communities that support sensitive species and fragile, irreplaceable resources. The MSCP’s goal is to prevent future endangerment of the plants and animals that are dependent on these habitats.

Within Crestridge there exist diverse and pristine landscapes and habitat types with acres of mature oak woodland, including many specimens of the rare Engelmann oak. It also features riparian areas with year round streams, and stands of mature willow, sycamore, cottonwood, and oak, as well as open woodlands, coastal sage scrub and chaparral. It is home to many sensitive and endangered species, including the California Gnatcatcher, the San Diego Horned Lizard, the Orange Throated Whiptail lizard, the Hermes Copper butterfly, and the world’s largest stand of Lakeside ceanothus, a rare wild lilac.

Regional Significance

Crestridge Ecological Reserve is a large island of habitat almost entirely surrounded by residential development. It is centrally located at the eastern edge of urban development between MSCP lands to the north of Interstate 8 and MSCP lands to the south of Interstate 8 and thus may function as a habitat linkage. It provides nesting and foraging habitat for raptor species, including the black-shouldered kite (Elanus leucurus) and Cooper’s hawk (Accipiter cooperi). The reserve supports a wide diversity of native butterflies and native plant species, including bunch grasses and sensitive herbaceous species. Crestridge supports the largest known populations of Lakeside ceanothus (Ceanothus cyaneus) and Hermes copper butterfly (Lycaena hermes). The coastal sage scrub habitat on the west end of the reserve may function as one of the “stepping stones” for coastal sage scrub birds, including the California gnatcatcher (Polioptila californica californica), in the Lakeside archipelago of coastal sage scrub.