In the U.S., invasive mammals are less common, and may not be as closely linked to masting as New Zealand’s invaders. Still, Chris Hoving, an adaptation specialist at Michigan’s Department of Natural Resources, says that masting is contributing to a growing feral swine invasion that could cost the state billions of dollars. “Pigs are a major mast consumer,” Hoving says. “More acorns, more hickory [nuts], more hard mast and soft mast would benefit them. [We’re] probably at the cusp of it becoming a major invasion.” More abundant food resources would only fuel the pigs’ expansion, and with it the diseases they’ve been known to carry, such pseudo-rabies, a viral disease prevalent in swine that can devastate livestock populations.
And in the U.S., along with feral pigs, invasive deer mice in the Southwest have been known to carry hantavirus. For this reason, among others, Tompkins would like to see other regions replicate his study. “Hopefully, this will motivate people looking at their own systems,” he says.