Location, Cities, People With a population of about 375,000, according to 1990 census figures, the Colorado Desert is the second least populous of the ten bioregions. Only the Modoc Bioregion has fewer people. The bioregion encompasses all of Imperial County , the southeastern portion of Riverside County , the eastern end of San Bernardino County , and the eastern portion of San Diego County . Its most prominent cities are Palm Springs, Rancho Mirage, El Centro, and the smaller, but landmark communities of Blythe, Coachella, and Calexico. The bioregion is home to the Fort Yuma Indian Reservation in Imperial County and Arizona, the Colorado River Indian Reservation in Riverside County, and the Campo and Manzanita Indian Reservations in San Diego County.
Imperial County has the state's lowest median family income.
Major highways are Interstate 10 in Riverside County, Interstate 8 in Imperial and San Diego counties, and State Highways 111 and 115 in Imperial County. Industries Some of the bioregion's best attractions are its natural resources. Picacho State Recreation Area on the Arizona border, operated by the state Department of Parks and Recreation, offers boat rides on the Colorado River from which can be seen migratory cormorants, mergansers, white pelicans, and wintering bald eagles, to name a few species. Trails into the rugged backcountry lead to the habitat of desert bighorn sheep, feral burros, golden eagles, and nesting prairie falcons. The refuge is operated by the state Departments of Fish and Game and Parks and Recreation, and the U.S. Fish and Wildlife Service.