Wild boars wreak havoc on the native ecosystems in the Great Smoky Mountains National Park. A pack can decimate an area overnight, their sharp hooves plowing up the ground as they dig about for grubs and roots, leaving a swath of destruction. They also devour food needed by other animals.

The park launched a program in the late 1970s to eradicate or at least reduce the population. Park rangers trap or kill an average of about 250 to 300 hogs a year. The park’s record year for hog removal was 1986 when 1,146 hogs were eliminated.

Wild boars found in the park today are a mixed breed. Their lineage is traced to a herd of European wild boar imported more than a century ago for a private hunting preserve in Graham County, N.C., which borders the park. Meanwhile, early farmers traditionally turned their domestic hogs lose in the woods to forage, giving rise to a population of feral hogs. The two interbred over the years.