Estero Río Colorado is an extensive delta where the Colorado River empties into the Gulf of California. The location is the state line between Baja California and Sonora, Mexico and is almost completely isolated from development. The geography consists of the islands of Montegue and Pelicano which form three mouths to the river: la Baja, Enmedio and el Abrigo. The southern section contains salt flats and a swamp called La Ramada.
For millennium, water from the Colorado River flowed into the Gulf of California creating a extensive and complex system of habitats supporting freshwater, brackish, and saltwater species. Today the water rarely reaches the sea and the wetlands area is about 5% of what it had been historically. The biodiversity of the area has decreased as well as plants, animals and marine life disappear. In June 1993, the Mexican government designated portions of the upper Gulf and lower Colorado River Delta as a bioreserve zone, managed by CONANP (La Comisión Nacional de Áreas Naturales Protegidas)
Estero Río Colorado is one of five WHSRN sites on the Gulf of California. On the eastern shore, in the state of Sinaloa lies: Bahía de Santa María (Hemispheric), Ensenada de Pabellones (International), and Playa Ceuta (Regional). Ensenada de la Paz is a Site of Regional Importance on the western shore in the state of Baja California Sur.
Ecology & Conservation
Morrison, Ross and Torres, in a January-February, 1992 aerial survey, counted 163,744 shorebirds of the following species:
The area was dedicated as the Islas del Golfo Biosphere Reserve in June of 1993 offering some degree of protection to the area.
The Colorado River Basin Salinity Control Project for desalination of irrigation returns to Colorado River could reduce amount of water leading to the Cienega de Santa Clara section and highly increase the salinity of remaining water returned to the canal that feeds this wetland.
Davis, O.K.(editor). 1990. quaternary Geology of Bahía Adair and the Grand Desierto Region. Deserts past and Future Evolution. IGCP 252.
Morrison, R.I.G. R.K. Ross, and Torres. 1992. Aerial surveys of Nearctic shorebirds wintering in Mexico: Some preliminary results. progress Notes No.201, July, 1992. Canadian Wildlife Service