Feral hogs spreading north; could threaten crops and more

Feral swine (U.S. Department of Agriculture photo)

Feral swine, which have plagued Southern states for years, have spread northward and have established colonies in places like Montana, North Dakota, and the Canadian prairie, Jim Robbins reports for The New York Times.

Feral hogs are more than a nuisance. They are "widely considered to be the most destructive invasive species in the United States. They can do remarkable damage to the ecosystem, wrecking crops and hunting animals like birds and amphibians to near extinction," Robbins reports. "They have wrecked military planes on runways. And although attacks on people are extremely rare, in November feral hogs killed a woman in Texas who was arriving for work in the early morning hours."

Feral hogs have roamed parts North America for centuries, mostly sticking to the southern half; about half of the six million feral swine in the U.S. live in Texas. But over the past 30 years, their range has expanded to 38 states from 17. "Many experts thought the pigs couldn’t thrive in cold climates. But they burrow into the snow in winter, creating so-called pigloos — a tunnel or cave with a foot or two of snow on top for insulation. Many have developed thick coats of fur," Robbins reports.

It's probably not an accident that feral hogs are appearing so far north, said Dale Nolte, manager of the feral swine program at the U.S. Department of Agriculture. "It’s not natural dispersion," Nolte told Robbins. "We have every reason to believe they are being moved in the backs of pickup trucks and released to create hunting opportunities."