A new report indicates the reintroduction of wolves has benefited the Greater Yellowstone Ecosystem. The study found that the wolves have kept the elk population in check, which in turn has allowed aspen, willow and cottonwood trees to re-grow in some parts of the park.
Study author Bill Ripple of Oregon State University says those types of trees are crucial to maintaining a vibrant ecosystem.
“Underneath an aspen grove, there can be shrubs growing berries, for example,” Ripple said. “The birds will be eating those berries, and the bears will be eating them, and some small mammals. So these woody plants are just magnets for wildlife.”
Wolves were killed off in the early 20th century, and were reintroduced to Yellowstone in the 1990s. Ripple says it’s too soon to tell what the long-term effects will be, but he says so far the presence of a so-called “apex predator” seems to be boosting the park’s biodiversity.
Ripple adds that there’s not much risk of Yellowstone’s wolf population growing too large.
“In recent years, the elk population has gone down, and the wolf population has followed in northern Yellowstone,” he said. “So wolves are somewhat self-regulating.”
Ripple says other studies from around the world support what he’s finding – that large predatory mammals are important for maintaining healthy ecosystems.