Yellowstone Wolves Are a Windfall for Trees

The reintroduced apex predators are helping restore the national park's biodiversity.
In the past decade, grey wolves have reduced surging elk numbers by nearly half. (Photo: Getty Images)
Jan 2, 2012· 1 MIN READ
Originally from Baltimore, Oliver lives and writes on a quiet, tree-lined street in Brooklyn.

After being hunted out of the area by ranchers and land owners early last century, the oft-maligned grey wolf is now being heralded in Yellowstone Park as a welcome harbinger of biodiversity.

According to the AP on Monday, the recently reintroduced wolf has successfully curbed the booming elk population and allowed for new stands of aspens, willows, and cottonwood trees to blossom in areas that had been grazed bare in recent decades. The study, authored by William Ripple and co-author Robert Beschta of Oregon State University, will be published in the scientific journal Biological Conservation.

Since being reintroduced to the national park in 1995, the 100 or so wolves have been able to reduce elk numbers from over 20,000 to 10,000 in just a decade and a half. The return of the apex predator—even bears and cougars rarely attempt to take down a full-grown elk—has created a domino effect on the area's ecosystem: with less elk, there is more vegetation and young trees to support the beavers, and with more beaver dams and ponds, there are more succulents, which restore a critical survival food for hibernating grizzlies awaking from their winter slumber. Even the carcasses the wolves leave behind play an important role in the park's delicate food chain, offering an important source of protein for the area's scavengers.

"We see bald eagles, golden eagles, coyotes, ravens and magpies on every kill that's made," said Douglas W. Smith, leader of the Yellowstone Wolf Project, to Scientific American in 2004. "I don't know what they did before wolves showed up."

Ecological success notwithstanding, the debate over reintroducing the grey wolf goes on. Not surprisingly, ranchers and land owners are less than thrilled about having the wolves running wild near their properties, and in some areas government wildlife officials have taken to shooting the animals from helicopters when they encroach upon livestock. Bowing to pressure, in May 2009, the government took the wolf off its Endangered Species list, making it legal for some states to manage wolf numbers on their own. But legal or not, many cattle owners aren't afraid to take matters into their own hands.

"Shoot, shovel and shut up," said Jim Baker, a rural Michigan cattle rancher, to Politico last month, adding that the wolves "could wipe me out in a couple of nights if they wanted."