Desert bighorn, one of three living subspecies of bighorn sheep, which once roamed 16 Texas mountain ranges. Their restoration success is important to the ecology of the Trans-Pecos region.
Known for their large horns, desert bighorn males are aged by the “rings” on their horns. They prefer a special type of habitat of high rugged mountain areas with little tree cover. They use the steep mountain slopes to avoid predators. Along the mountain slopes, desert bighorn browse for their food, eating new growth, fruits, and leaves from a variety of woody shrubs.
Desert bighorn range sizes vary considerably across the Trans-Pecos. Along the Rio Grande, bighorn move over hundreds of thousands of acres to acquire the resources they need. Whereas in higher elevation areas, that receive more precipitation, habitat is more connected and bighorn occupy relatively small, stable ranges of only a few thousand acres.
Historically, populations of desert bighorn were thought to number between 1,000 and 1,500 individuals in the late 1800s. By the 1930s population numbers fell to around 300 individuals in only four ranges. By 1960, desert bighorn sheep were gone.
With no bighorn left in Texas, restoration efforts began in the mid-1950s, led primarily by Texas Parks and Wildlife Department (TPWD), Texas Bighorn Society (TBS), and various conservation organizations. These initial labors were primarily in the form of captive propagation, however, they had little success.
In the last 20 years, restoration efforts have been more successful, though. Through exchange programs with other western states and translocations, self-sustaining bighorn populations were reestablished in several of the historically sheep-occupied ranges. Tracking translocated sheep, with the aid of GPS technology, has taught researchers and biologists many factors about their ecology.
Partnerships with agencies and private landowners to provide restoration efforts, is the driving force behind the success of management of desert bighorn sheep in Far West Texas.