Feral hogs compete with native species in Big Bend National Park.
Earlier this year the National Park Service invited public comments on a plan to manage non-native, exotic animals in Big Bend National Park. The 30-day review and comment period for the park’s Exotic Animal Management Plan and Environmental Assessment ended in February and the verdict is now in. On June 13, 2018 Regional Director Sue Masica signed the decision document, a finding of no significant impact (FONSI), that will allow for limited aerial shooting as well as live trapping of these non-native species, using the most humane feasible methods.
“These invasive animals threaten the native plants and animals the park is mandated to protect,” says Acting Superintendent Tom Forsyth. “This plan provides the framework to manage them while minimizing the effects on park visitors. This plan will aid park management as we steward these resources for future generations.”
To protect the park’s natural and cultural resources and the visitor experience, the National Park Service will manage aoudad (Barbary sheep) and feral hogs using lethal means. Control of these populations as proposed as these non-native species compete with and consume native species, alter species composition, threaten biodiversity, and impair the visitor’s ability to experience natural conditions and scenery.
Aoudad have been in the park for the past three decades, and have increased significantly in recent years. Estimates suggest 200 to 400 aoudads now inhabit the park. Aoudads are major competitors to native desert bighorn sheep. Feral hogs are present in low numbers in the park’s northern extremity, and are expected to invade the heavily vegetated, 113-mile Rio Grande corridor in coming years. Additionally, the park wishes to prevent feral hogs from invading the Chisos Mountains, a small range within the park that contains rare montane woodlands and hosts endangered, rare and isolated native species.
Control actions will employ the most humane feasible methods. No poisons, snares, or leg-hold traps will be used. Only lead-free bullets would be used to minimize impacts to scavengers. Aerial control of aoudads and feral hogs would primarily occur during the hot summer months, when few visitors use the park’s backcountry. Aerial control would likely occur only several days per year, and a total of 20 days per year would be the maximum allowable helicopter use for all aspects of exotic aoudad and feral hog management. Ground-based control would occur during many times throughout the year, but would avoid the busier visitor use periods and locations.