San Bernardino National Wildlife Refuge
Encyclopedia
The San Bernardino National Wildlife Refuge is located on the U.S.
-Mexican
border in Cochise County, Arizona
. Situated at 3,720 to 3920 feet (1,194.8 m) elevation in the bottom of a wide valley, the refuge encompasses a portion of the headquarters of the Yaqui River
, which drains primarily western Chihuahua and eastern Sonora
, Mexico.
The 2309 acres (9.3 km²) ranch
was acquired by the U.S. Fish and Wildlife Service in 1982 to protect the water resources and provide habitat
for endangered native fishes.
This area is part of the basin and range
geologic region, characterized by linear mountain ranges which are separated by broad, flat basins. The region was impacted by relatively recent volcanic
activity, leaving volcanic plug
s and cinder cone
s visible throughout the San Bernardino Valley (Arizona)
. Earthquake
s have further altered the region and helped allow the flow of many springs and seeps. All of these dynamic geological events have played major roles in shaping the valley, catching and storing crucial water, helping determine the variety of plants and animals present, and creating a beautiful landscape for humans to enjoy.
The San Bernardino Valley once supported permanently flowing creeks, springs, and marshy wetlands. In addition, the giant sacaton grassland in the valley was once described as "a luxuriant meadow some eight or ten miles long and a mile wide." The dependable source of water and grass made the area not only invaluable to a huge diversity of fish and wildlife, but also a center of human activity for centuries.
With expanding settlement beginning in the late 19th century came farming, mining
, and livestock
production, all of which competed for the same precious water. While the extensive wetland
s here once provided historic habitat for eight different kinds of native fish, the lowering water table led to severe changes in the habitat and the eventual local extinctions of many species.
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
-Mexican
Mexico
The United Mexican States , commonly known as Mexico , is a federal constitutional republic in North America. It is bordered on the north by the United States; on the south and west by the Pacific Ocean; on the southeast by Guatemala, Belize, and the Caribbean Sea; and on the east by the Gulf of...
border in Cochise County, Arizona
Cochise County, Arizona
-2010:Whereas according to the 2010 U.S. Census Bureau:*78.5% White*4.2% Black*1.2% Native American*1.9% Asian*0.3% Native Hawaiian or Pacific Islander*4.0% Two or more races*9.6% Other races*32.4% Hispanic or Latino -2000:...
. Situated at 3,720 to 3920 feet (1,194.8 m) elevation in the bottom of a wide valley, the refuge encompasses a portion of the headquarters of the Yaqui River
Yaqui River
The Yaqui River is a river in the state of Sonora in northwestern Mexico. Being the largest river system in the state of Sonora, the Yaqui river is used for irrigation....
, which drains primarily western Chihuahua and eastern Sonora
Sonora
Sonora officially Estado Libre y Soberano de Sonora is one of the 31 states which, with the Federal District, comprise the 32 Federal Entities of Mexico. It is divided into 72 municipalities; the capital city is Hermosillo....
, Mexico.
The 2309 acres (9.3 km²) ranch
Ranch
A ranch is an area of landscape, including various structures, given primarily to the practice of ranching, the practice of raising grazing livestock such as cattle or sheep for meat or wool. The word most often applies to livestock-raising operations in the western United States and Canada, though...
was acquired by the U.S. Fish and Wildlife Service in 1982 to protect the water resources and provide habitat
Habitat
* Habitat , a place where a species lives and grows*Human habitat, a place where humans live, work or play** Space habitat, a space station intended as a permanent settlement...
for endangered native fishes.
This area is part of the basin and range
Basin and Range
The Basin and Range Province is a vast physiographic region defined by a unique topographic expression. Basin and Range topography is characterized by abrupt changes in elevation, alternating between narrow faulted mountain chains and flat arid valleys or basins...
geologic region, characterized by linear mountain ranges which are separated by broad, flat basins. The region was impacted by relatively recent volcanic
Volcano
2. Bedrock3. Conduit 4. Base5. Sill6. Dike7. Layers of ash emitted by the volcano8. Flank| 9. Layers of lava emitted by the volcano10. Throat11. Parasitic cone12. Lava flow13. Vent14. Crater15...
activity, leaving volcanic plug
Volcanic plug
A volcanic plug, also called a volcanic neck or lava neck, is a volcanic landform created when magma hardens within a vent on an active volcano. When forming, a plug can cause an extreme build-up of pressure if volatile-charged magma is trapped beneath it, and this can sometimes lead to an...
s and cinder cone
Cinder cone
According to the , Cinder Cone is the proper name of 1 cinder cone in Canada and 7 cinder cones in the United States:In Canada: Cinder Cone In the United States:...
s visible throughout the San Bernardino Valley (Arizona)
San Bernardino Valley (Arizona)
The San Bernardino Valley of Arizona is a northeast by southwest trending valley in extreme southeast Cochise County, Arizona.The north end of the valley merges into the northwest by southeast trending San Simon Valley; both merge in western Hidaldgo County, New Mexico...
. Earthquake
Earthquake
An earthquake is the result of a sudden release of energy in the Earth's crust that creates seismic waves. The seismicity, seismism or seismic activity of an area refers to the frequency, type and size of earthquakes experienced over a period of time...
s have further altered the region and helped allow the flow of many springs and seeps. All of these dynamic geological events have played major roles in shaping the valley, catching and storing crucial water, helping determine the variety of plants and animals present, and creating a beautiful landscape for humans to enjoy.
The San Bernardino Valley once supported permanently flowing creeks, springs, and marshy wetlands. In addition, the giant sacaton grassland in the valley was once described as "a luxuriant meadow some eight or ten miles long and a mile wide." The dependable source of water and grass made the area not only invaluable to a huge diversity of fish and wildlife, but also a center of human activity for centuries.
With expanding settlement beginning in the late 19th century came farming, mining
Mining
Mining is the extraction of valuable minerals or other geological materials from the earth, from an ore body, vein or seam. The term also includes the removal of soil. Materials recovered by mining include base metals, precious metals, iron, uranium, coal, diamonds, limestone, oil shale, rock...
, and livestock
Livestock
Livestock refers to one or more domesticated animals raised in an agricultural setting to produce commodities such as food, fiber and labor. The term "livestock" as used in this article does not include poultry or farmed fish; however the inclusion of these, especially poultry, within the meaning...
production, all of which competed for the same precious water. While the extensive wetland
Wetland
A wetland is an area of land whose soil is saturated with water either permanently or seasonally. Wetlands are categorised by their characteristic vegetation, which is adapted to these unique soil conditions....
s here once provided historic habitat for eight different kinds of native fish, the lowering water table led to severe changes in the habitat and the eventual local extinctions of many species.