Five years after 49 bighorn sheep burst from trailers and charged up scrub-covered hillsides at Big Bend Ranch State Park, experts say their population is holding steady, despite challenges from drought, predators and unfamiliar terrain.
Desert bighorn sheep, with their thick, gnarled gray horns, once roamed the rugged mountains of northern Mexico and Far West Texas. Unregulated hunting and disease carried by domestic and exotic livestock obliterated their numbers. By 1960, they were gone.
Conservation groups and private ranch owners have worked for decades to bring them back. Wildlife experts consider them a flagship species, helping to drive cross-border wildlife conservation efforts, as well as an indication of the area’s environmental health.
“I firmly believe they belong out here,” said biologist Froylán Hernández, head of the Texas Parks and Wildlife Department’s Desert Bighorn Sheep Program in Alpine. “They formed part of the ecological niche, and there was a void once they were gone. They need to be back here to be part of a functioning ecosystem.”
Bighorn sheep like steep, rocky slopes with minimal vegetation; that’s why Big Bend Ranch State Park, which is crisscrossed with rugged canyons and bristles with cactus, was chosen as a release site. Biologists hope the animals here will intermingle with other groups in northern Mexico, creating genetic diversity and more robust herds.
The repopulation effort hasn’t been easy. Bighorn sheep must compete with non-native species such as burros and aoudads, or Barbary sheep, an African import, for resources such as food and water. Aoudads carry diseases that threaten the bighorn. Bighorn sheep are also a favorite meal of the area’s mountain lions.