Coyotes give way to wolves
By The Associated Press
The resurgent wolf population in the greater Yellowstone area is causing a sharp decline in another predator – coyotes – which are being killed off and scared away by their larger, more aggressive canine cousins, according to a new study.
Coyote numbers in Yellowstone National Park dropped by almost 40 percent since wolves were reintroduced there in the mid-1990s, according to the study. In neighboring Grand Teton National Park, coyote numbers are down 33 percent where wolves have moved in.
Both species prey on wildlife and livestock. But because wolves are so much larger – averaging more than 85 pounds, almost three times the size of the coyotes in the study – their resurgence means more attacks on larger animals such as elk or cattle.
It also means less pressure on smaller prey, such as sheep, lambs and fawns of deer and pronghorn antelope, said Kim Murray Berger of the Wildlife Conservation Society. Berger co-authored the federally funded study with Eric Gese of the U.S. Department of Agriculture.
Berger said another study, still in the works, suggests pronghorn numbers have risen by 6 percent a year in areas where wolves are replacing coyotes.
Berger compared the realignment of predator and prey in the Yellowstone area to the balance in place a century ago, before wolves were exterminated from much of the West.
“You saw all the attention shift to coyotes,” she said, noting the creation of a federal program that now kills 70,000 to 80,000 coyotes a year for livestock protection.
“As some of the larger predators have been expanding, the attention is shifting back,” she said.