YELLOWSTONE NATIONAL PARK – Wolves continue to reshape the ecosystem in Yellowstone National Park, sometimes in surprising ways. For the first time in eight decades, new aspens are growing and maturing in the northern part of the park.
New research finds that the trees’ resurgence is linked to the reintroduction of gray wolves in 1995 because those apex predators are now keeping elk populations in check. There were so many elk wintering in the park—17,000 in fact—that they were eating all the aspen sprouts, preventing them from growing into trees. At one point in the 1990s, ecologists couldn’t find a single sapling in all of Yellowstone.
Now, the elk population is down to 2,000 elk in the winter, which is giving the aspen saplings a chance to survive and grow. That’s good news for other animals, like woodpeckers and beavers, which eat the tree bark and use the branches for dams.
“This is a remarkable case of ecological restoration,” said the study’s lead author, Luke Painter, who teaches ecology and conservation at Oregon State University. “Wolf reintroduction is yielding long-term ecological changes contributing to increased biodiversity and habitat diversity.”
The research was published in Forest Ecology and Management.
NATIONAL PARK NEWS
