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Biologist probes predation on elk JACKSON, Wyo. (AP) - Biologists hope to find out how many elk calves are being killed by wolves moving into Jackson Hole. Bruce Smith, a biologist at the National Elk Refuge, has been studying which predators kill elk calves in early summer and how the ratio of animals behind the predation changes over time. Smith hopes to compare the results of his three-year study with the findings of a similar study between 1990 and 1992. Sometime between the studies, biologists believe, more grizzly bears moved into Jackson Hole. Also, Grand Teton National Park is now home to the first wolves known in the valley in more than 50 years. Smith wants to find out if the predators have affected elk numbers and other predator populations. "A person could hypothesize that wolf predation would be added to other forms of predation in the area," he said. "We're testing that hypothesis." Using a helicopter, Smith has captured and tagged up to 60 elk calves, including 31 this year. He plans to continue the operation until June 9. "Use of a helicopter greatly increases the efficiency of capture, and results in the least disturbance to elk cows and calves," Smith said. The tag emits a signal if the calf dies. Smith plans monitor for mortality signals twice a day in the morning and evening well into the summer. Smith's goal is to get to the scene within 24 hours of the time the elk calf was killed. If he can do that, it greatly increases his chances of learning what killed it, he said. Bears, mountain lions, coyotes and wolves all have different ways of killing an elk calf. Smith also looks for tracks, scat and - perhaps most importantly - hair from the predator that made the kill. In past studies, Smith found that the usual predators including black bears, mountain lions and coyotes killed most of the elk calves. But while no grizzly bears killed calves in the earlier study, Smith confirmed four instances of grizzly bears making kills in the last two years. In past years, Smith's team has monitored for calves killed by predators until early July. Once elk calves reach about six weeks of age, it is much more difficult for bears and coyotes to kill them, he said. But wolves are able to kill older animals, and so this year the team will continue monitoring until later in the summer. "It creates more of a work load because wolves are capable of killing these animals at any age," he said. The study is being funded by both federal and state wildlife management agencies, the Community Foundation of Jackson Hole, the Rocky Mountain Elk Foundation, the University of Wyoming and Wildlife Forever. Copyright 1999 Associated Press. All rights reserved. This material may not be published, broadcast, rewritten, or redistributed.
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