In February of 2004, a mountain lion (Felis concolor) killed a large bull elk (Cervus elaphus canadensis) near a Rocky Mountain National Park trail. This kill is a bit unusual because mountain lions usually prefer to prey on mule deer (Odocoileus hemionus,) the smaller relative of elk. Although adult mountain lions in the vicinity of the park are thought to range between 80 and 180 pounds and an average bull elk weighs about 750 pounds, elk sometimes fall prey to mountain lions. Some possible reasons for this may be because the elk is not healthy, because its escape is hampered by snow, or because it just happens to walk too near a hungry mountain lion.
Because the kill was reported quickly, and because the mountain lion chose to cache the uneaten remainder of the elk near a trail, it was possible for scientists doing research in the park to capture the lion and fit him with a tracking collar. Colorado Division of Wildlife researchers have a permit to collar up to three mountain lions in the park for the purposes of determining whether or not mountain lions prefer to prey on Chronic Wasting Disease infected deer and elk rather than on healthy animals. If this is the case, mountain lions may help to slow the spread of this destructive disease. In a second project, a U.S. Geological Survey researcher used the same data to try to get some idea of the number, ages, and sexes of park mountain lions, what they eat, and what type of habitat they prefer. Hopefully this information will help the park staff understand how to manage them and how to minimize the number of human-mountain lion conflicts.
It is very important to park staff, when they review applications by qualified researchers to conduct their work in the park, to assure that the research proposed does not permanently harm park resources, and that it causes the absolute minimum short term impact. It is ideal when more than one research project can use the same animals and share data. This minimizes the number of animals that must be handled and collared.