Presence of wolves allows aspen recovery in Yellowstone

CORVALLIS, Ore. – The wolves are back, and for the first time in more than 50 years, young aspen trees are growing again in the northern range of Yellowstone National Park.

The findings of a new study, just published in Biological Conservation, show that a process called “the ecology of fear” is at work, a balance has been restored to an important natural ecosystem, and aspen trees are surviving elk browsing for the first time in decades.

The research, done by forestry researchers at Oregon State University, supports theories about “trophic cascades” of ecological damage that can be caused when key predators – in this case, wolves – are removed from an ecosystem, and show that recovery is possible when the predators are returned. The results are especially encouraging for the health of America’s first national park, but may also have implications for other areas of the West and other important predators.