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The Land and Water Trust protects Southern Arizona's vanishing western landscapes and wildlife habitat by acquiring and managing sensitive lands.

Couch’s spadefoots range from southeastern California through southern Arizona and southern New Mexico. During summer monsoons, the spadefoot emerges from its subterranean estivation to breed in the temporary ponds created by the heavy runoff. The cue for emergence is not moisture, but low frequency sound or vibration, most likely caused by rainfall or thunder. (Photo: ALWT)

where we woRk
After the rain, the earthy smell of creosote fills the air as sunlight silhouettes the spines of a saguaro cactus and its nurse palo verde tree.  The contented cooing of a mourning dove greets an exquisite rainbow displayed against billowing purple clouds over the rugged mountains nearby.  This is a summer monsoon day in the otherwise arid vastness of the Sonoran Desert.

Most of southern Arizona is part of this Desert which extends west into California and south into Mexico.  Because of its seasonal rainfall—a "wet" and "dry" summer, and a mild winter—it is lush compared to other deserts and has the greatest diversity of plants of any desert in the world.  The tenacious beauty of the Desert’s distinctive  saguaro cacti, legume trees, and wild creatures surprises and inspires us.  The Sonoran Desert supports over 550 species of vertebrates, and thousands of invertebrate species.  At least 96 species of reptiles are native to this Desert.

Arizona’s riparian heritage is closely tied to the fate of the Gila River—the largest desert river in the U.S., and a linchpin of global bird diversity.  The Basin encompasses two-thirds of the state, including bustling urban centers in Phoenix, Tucson, and Casa Grande.  Desert rivers and cottonwood-willow canopies thread through the Santa Cruz, San Pedro, and Verde Valleys within the Gila River Basin, attracting global conservation interest.

These Rivers and their tributaries are  ribbons of life that have supported humans and wildlife in the Desert for thousands of years.  The Santa Cruz is a natural treasure for three nations:  the United States, the Tohono O'odham, and Mexico.  Riparian areas along the banks of the Santa Cruz and its perennial tributaries offer both habitat and migration stopovers for a dramatic diversity of birds including species that people come here especially to see:  the elegant trogan, common black hawk, northern beardless tyrannulet, broad-billed hummingbird, Montezuma quail, and buff-breasted flycatcher.  Of the 36 species of raptors that nest in Arizona, 31 do so in the Santa Cruz watershed.  Over 86 species of mammals range within the San Pedro National  Riparian Area alone, more than in any natural landscape of comparable size within the U.S.

Southern Arizona’s landscape of wonder, beauty, wildness, and astonishing biological diversity, is part of the "Sky Island" region.  The cool, moist communities on upper elevations of 27 mountain ranges are isolated from one another by "seas" of hot, arid habitat.  The Sky Island "archipelago", unique on the planet, is among the most diverse ecosystems in North America due to its topographic relief and location at the convergence of desert and forest.  Jaguar, coatimundi, Mexican long-nosed bat, elegant trogan, violet-crowned hummingbird banded rock rattlesnake, 18 species of bats, more than 400 species of birds, and about 100 species of butterflies thrive here.  Herds of the rare desert bighorn sheep survive in the most remote terrain. 

Southern Arizona has been occupied continuously for approximately 12,000 years, and the Santa Cruz Valley is the home of two Native American tribes—the Tohono O'odham (People of the Desert) since prehistoric times, and groups of the Yaqui (Yoeme) tribe of western Mexico who arrived here beginning in the early 1800's.  Ranching and farming have been mainstays of the rural economy for more than 300 years—since the Spaniards introduced cattle, horses, and other livestock in the late 1600's.  Today, the interplay of Hispanic, American, and Native American ranching continues our area’s historical and living tradition.

Most of southern Arizona’s open space is used for ranching and most ranches include both privately owned and leased public lands.  Typically, ranches are owned by descendants of homesteaders who started ranching in the late 1800s.  In the face of mounting development pressures, ranchers have provided ongoing land stewardship and management of unfragmented open space, habitat, and the land's natural and cultural resources, including many archaeological treasures.  Conservation of working ranchlands can protect vast areas of open space, maintain habitat connectivity, and preserve our area’s Southwestern heritage.