Colorado State University researchers find reintroduction of wolves doesn't have rapid impact on ecosystems in Yellowstone
Researchers with Colorado State University spent two decades studying the ecosystems in Yellowstone National Park, with the goal of learning whether or not the reintroduction of wolves had any rapid impacts on willows and beavers.
After more than 20 years of collecting data, the researchers found the reintroduction of wolves did not have a rapid or notable impact on those ecosystems in the park.
David Cooper and Tom Hobbs, research scientists with CSU, said the removal of wolves from ecosystems has a much more rapid impact on the area than the reintroduction does.
"When you take top predators like wolves, grizzly bears and cougars, bad things can happen to the ecosystem," said Hobbs said.
Hobbs said the researchers specifically focused on riparian areas in Yellowstone.
"A riparian area is all the vegetation that exists alongside streams and rivers," Hobbs said.
The researchers found the removal of wolves had a major impact on the vitality of the streams and rivers, and the ecosystems around them. When the predators, such as wolves, were removed, the elk population rapidly grew. Those elk then consumed the willows in the area, removing food and building resources for the area beavers. Therefore, beavers could not survive, and in turn could not build dams that helped improve water tables.
Getting those willows and beavers to return naturally is very difficult.
"The extirpation of wolves and other predators causes changes in ecosystems that persist for a long period of time," Cooper said.
Colorado recently reintroduced wolves to the Rocky Mountains in-state. The researchers noted that Colorado and Yellowstone are drastically different places. They also noted Colorado has managed the elk population fairly well through hunting and more.
Hobbs and Cooper couldn't directly predict that the reintroduction of wolves in Colorado would have significant impacts on the ecosystems in our state. However, they did say it is safe to assume any changes to things like willows would take a very long time to notice.
"Reintroducing the predators doesn't change things very quickly. It takes a long-long time," Cooper said. "I'm not sure if the reintroduction of wolves can result in the restoration of these riparian areas even in the long-term."
Though there may not be drastic differences made with wolves now reintroduced, when it comes to willows and beavers, Cooper and Hobbs said the wolves are still natural predators and pieces of the ecosystem.
"If you lose a piece, it is probably a good idea to put it back. And, that is supported in the long term," Hobbs said.
