Associated Press
More gray wolves mean more pronghorn antelope in the Yellowstone area, according to researchers who say the region's rebounding wolf population is killing and scaring off coyotes that otherwise prey on pronghorn.
The researchers said that during a three-year study, pronghorn fawns were three times more likely to survive in areas dominated by wolves versus those ruled by coyotes. That's because wolves favor larger prey, such as elk or cattle, and generally leave pronghorn alone.
The findings appear in the latest issue of the journal Ecology.
Predators
Pronghorn weigh between 75 and 130 pounds (between 34 and 60 kilograms) and are about three feet (one meter) tall. They are widely distributed across the Great Plains.
"People tend to think that more wolves always mean fewer prey," said Kim Berger, the study's lead author. "But in this case, wolves are so much bigger than coyotes that [it] doesn't make sense for them to waste time searching for pronghorn fawns."
Wolf numbers have soared since the predators were reintroduced to the Yellowstone National Park region in 1995 and 1996. So, too, have pronghorn, increasing by about 50 percent in Grand Teton National Park, part of the Yellowstone area, according to the study.
Meanwhile coyote and elk populations are declining. Coyote numbers in Yellowstone are down almost 40 percent and an elk herd at the northern end of the park has declined almost 70 percent since wolves were reintroduced.
The federal government is in the midst of removing Endangered Species Act protections for gray wolves in Wyoming, Montana, and Idaho—the three states that border Yellowstone. (See story.)
The researchers warned that state plans to hunt wolves beginning this fall could have the unintended effect of decreasing pronghorn numbers.
The federally funded study was co-authored by Eric Gese and Joel Berger with the New York-based Wildlife Conservation Society.
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