Since the late 1980s, fawning cover has been very limited in the Trans-Pecos. Predators detect movement to locate prey. Without herbaceous cover, a significant number of fawns annually fall prey to coyotes within 30 days of birth. They are lying out there on what amounts to a huge parking lot. Anytime they raise their heads, a coyote can see them from a mile away.
Fences also work against adult pronghorns trying to escape from coyotes.
Coyotes have learned to use fences to slow or stop pronghorns and catch them. Just as the old buck used a fence to corner the does, coyotes use fences to ensnare their victims. Decreased predator control efforts by landowners as land use transitioned from sheep and goat ranching to cattle ranching resulted in more coyotes. And the sale and division of many ranches in recent years brought on a spate of fence-building in West Texas. More coyotes have more fences to help them catch more pronghorns.