Ciénega Creek

From its origin in the Canelo Hills of Santa Cruz County at , Ciénega Creek flows northwesterly through the upper Ciénega basin, a wide alluvial valley separating the northern Santa Rita and Empire Mountains to the west and the Whetstone Mountains to the east. A bedrock high, called "the Narrows," serves as a hydrologic barrier dividing the upper and lower basins, and is characterized by riparian vegetation and perennial flow. Ciénega Creek continues northward through the lower alluvial basin until it bends west/northwest in the vicinity of Anderson and Wakefield Canyons. After crossing Interstate 10 near the town of Vail, Ciénega Creek again crosses a bedrock high, and once more the flow becomes perennial. In these stretches, groundwater is forced upward through faults in the bedrock from aquifers near the surface. Just north of Vail, Ciénega Creek becomes known as Pantano Wash, which continues northwest through Tucson and links up with the Rillito River. ==Flora and fauna==

Ciénega Creek is located within the transitional zone between the Sonoran and Chihuahuan Deserts, and exhibits some features of each region. The creek supports "outstanding examples" of cottonwood-willow gallery forest and mesquite bosque, which are home to many bird species that have become rare due to the loss of riparian habitats. Some of the birds that live along the creek are the Southwestern willow flycatcher, Yellow-billed cuckoo, and Bell's vireo. ==Conservation==

Las Cienegas National Conservation Area was established in 2000 to protect the upper Ciénega basin. Its headquarters is the historic Empire Ranch, which is located about southeast of Tucson, near the town of Sonoita. Spanning , Las Cienegas includes large areas of grassland and woodland, in addition to Ciénega Creek and the riparian corridor. Empire Ranch, which dates back to the 1870s, is also open to the public, and has been listed on the National Historic Register since 1976. ==Gallery==

File:Cienega Creek Arizona 1880.jpg|Ciénega Creek in 1880 File:Cienega_Creek_Natural_Preserve_Pima_County_Arizona_2014.jpg|View of Ciénega Creek, at the Ciénega Creek Natural Preserve File:Las Cienegas NCA.jpg|View of Ciénega Creek, in the Las Cienegas National Conservation Area File:Cienega_Creek_Natural_Preserve_Entrance_Arizona_2014.jpg|The sign at the entrance to the Ciénega Creek Natural Preserve File:Cienega_Creek_Natural_Preserve_Signs_Arizona_2014.jpg|Signs at the Ciénega Creek Natural Preserve, including a memorial for Jimmie Mercer, who was ambushed by a cattle rustler near Pantano in 1914 File:Cienega_Creek_Natural_Preserve_Bridge_Marker_Arizona_2014.jpg|A historical marker for the Ciénega Bridge at the Ciénega Creek Natural Preserve, with the bridge in the background File:Prehistoric_Bedrock_Mortar_Davidson_Canyon_Arizona_2014.jpg|Hohokam bedrock mortar in Davidson Canyon, near its confluence with Ciénega Creek File:Pantano_River_Park_Sign_Tucson_Arizona_2014.jpg|A sign at the entrance to the Pantano River Park in Tucson ==See also==