Berries returning to Yellowstone bears’ diets thanks to wolves, study finds

Aug 1, 2013

A new study shows that berries, a staple of the grizzly bear diet, are becoming more abundant at Yellowstone National Park. According to the study, over the past three years berry consumption by bears has nearly doubled, something the authors are contributing to the reintroduction of wolves.

Study co-author Bob Beschta says the lack of wolves during the past century led to more elk, which overgrazed plant life in the area for decades. Now, the wolves are helping to re-balance the ecosystem.

“We see it not only in the berries, but we see it in the aspen, the cotton woods, willows, and other plants have also been heavily utilized,” says Beschta. “So with wolves back, we are beginning to see this interesting reversal of fortunes for these plant communities.”  

Beschta says the results are preliminary, and that berries still make up a small part of Yellowstone bears’ diets compared with those of bears in other regions.