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The southwest used to be jaguar country. In the 18th century, the big cats were common in Texas, Arizona, New Mexico, and California, roaming across millions of acres of coniferous forest as far north as the rim of the Grand Canyon. But in the early 20 century, ranchers and government-funded predator control programs killed off the entire population of the animals in the United States.
In the last decade, however, a small handful of jaguars have reappeared in the United States after migrating across the Mexican border. “Our dream is that we’ll one day have a breeding population of jaguars in the U.S. again,” says Rob Peters, Senior Southwest Representative of Defenders of Wildlife.
But with the White House continuing to push ahead with plans to construct a border wall, that dream could be in jeopardy. From jaguars to Mexican gray wolves to bighorn sheep, the wall could halt the natural migration of threatened and endangered wildlife across the United States’ southern reaches.
Ben Masters, a wildlife biologist and filmmaker, knows what’s at stake better than most. The lifelong Texan recently took a 3-month horse-and-canoe trip down 1,200 miles of the Rio Grande river that makes up the U.S.-Mexican border to document the natural scenery before a wall cuts off its viewshed entirely. Wildlife and the Wall, his new short film on the journey, debuted at Mountainfilm Festival in Telluride earlier this year.
“I was thinking some of the sights I saw might be the last time anyone ever saw them,” he says. If plans for the border wall actually go through, “these could be the last photos that exist of those landscapes before a 30-foot wall is obstructing them.” The topographical magnitude of the terrain comes across in the film, which juxtaposes gorgeous landscape shots with cheering, whooping crowds from the political rallies where President Trump pushed his border plan.
There’s little doubt that the impact of the border wall on wildlife would be severe. Last year, the Center for Biological Diversity released a study citing 93 endangered species that the wall would threaten. The head-ramming sheep in Masters’s film compete with other males for breeding rights in this region. Black bears, previously extirpated in West Texas, have naturally recolonized the U.S. side of the border, a rare feat for megafauna without human intervention. In addition to cutting off a crucial water source for all animals, the border wall would block any chance of future dispersal of these black bears and leave the small Texas population genetically isolated, unable to sustain itself.
“In the past, populations have only been separated by mountain ranges or changes in the oceans,” Masters says. “A thousand-mile wall would halt all terrestrial movement of life on a continental scale, which is almost unprecedented in human land use.”
Due to the rugged landscape, parts of the wall would have to be built several miles north of the actual border, leaving millions of acres of inaccessible no-man’s land within American territory. The Bentsen-Rio Grande Valley State Park is a destination for world-class birding, with more than 500 documented species ranging from Mexican ducks and blue-winged teals to more than a dozen varieties of kite and hawk. The planned wall would cut right through the heart of the reserve, disrupting both wildlife and human visitors
“I wish that everybody who wanted to build an actual, physical wall could come and see this place first, because I think that if they came and saw it, and realized what the wall would go through and what it would do, it would have a profound impact on their way of thinking,” Masters says toward the end of his film. And after seeing a snippet of the terrain that makes up the border, viewers may find it hard to disagree.