Should Assisted Migration Be Used To Move Whitebark Pines Outside Of Their Native Habitat?

Eighty percent of terrain that’s currently suited climatically for whitebark pines will, by mid-century, be too warm to support the trees, a recent study predicts. But it also finds that suitable terrain does exist elsewhere in the West.

So, does that mean an ambitious effort around assisted migration should be launched in a bid to save the threatened species? Is it wise to take whitebark pine seedlings and plant them in other Western locales where the species never was native but where the climate would allow them to flourish?

“You can have areas that are currently climatically suitable, and whitebark pine isn't there,” pointed out Sean A. Parks, the lead author on the paper that predicted the massive loss the pine’s habitat in the coming decades. “Like, the Bighorns (in Wyoming) and the Uinta’s (in Utah), for example.”

He made a point not to refer to those areas as “future whitebark pine range” because those areas never grew the pines, and there are no nearby populations from which Clark’s nutcrackers would carry whitebark seeds and plant them in those areas.

Parks also shied away from assisted migration as a solution – meaning humans transplanting the trees from current at-risk habitat into places where they are not native. “Introducing species outside of their range has these unintended and cascading consequences,” he explained

Though not a case of assisted migration related to climate change, the case of nonnative lake trout being dumped into Yellowstone Lake in Yellowstone National Park is one example of unintended consequences, where the bigger lake trout preyed extensively on the lake’s native, and smaller, Yellowstone cutthroat trout.

Elizabeth Pansing, who works on whitebark pine restoration for American Forests, a tree-advocacy organization, agreed with Parks that it’s not time to discuss assisted migration for the species.

“I don't think that most land management agencies are at a place where they want to consider assisted species migration,” she said. “I think it's considered a little bit too risky. We'll see how those conversations progress, but at this point there's just not a lot of social buy-in for that kind of large-scale movement of species.

“… I think there's merit for experimentation and very controlled experiments, but in terms of operationalizing that, I think we're a ways off from getting any real buy in.”