The historical value of gray wolves may be neglected in ecological research

Many researchers in national parks across the West have failed to take into account the historical impact of gray wolves, according to a new report.

Before the 1930s, gray wolves were among the most widespread large carnivores in the American West, said one of the study’s authors, William Ripple, a professor of ecology at Oregon State University.

“So they were ubiquitous before humans eradicated them in many areas,” Ripple added.

He said this had led to a sharp increase in moose and deer populations, causing overgrazing and plant damage, thus affecting the ecosystem’s biodiversity.

In Yellowstone National Park, researchers found that the elk population increased after wolves were removed from their winter quarters, causing erosion and the destruction of aspen and willow stands.

But Ripple said 60 percent of the ecological studies he examined failed to mention the historical presence of gray wolves.

“For the environment, this is the same as diagnosing a sick patient without conducting a basic medical examination,” he said.

Ripple said some ecosystems — like Yellowstone’s — are gradually recovering thanks to the reintroduction of wolves. The presence of the park’s top predator has kept the elk on the move. In the past, elk fed on aspen and willow, so those trees have now recovered from intensive grazing.

Still, researchers and policymakers across the West should recognize how humans altered the landscape by driving species extinct decades ago, Ripple said.

This comes as heated debates take place in many Western countries over the best methods for reintroducing and controlling the species.

This story was produced by the Mountain West News Bureau, a collaboration among Wyoming Public Media, Nevada Public Radio (KNPR) in Las Vegas, Boise State Public Radio in Idaho, KUNR in Nevada, KUNC in Colorado and KANW in New Mexico, with support from affiliate stations throughout the region. Funding for the Mountain West News Bureau is provided in part by the Corporation for Public Broadcasting.