Wyoming’s Proposed Mountain Lion Trapping Bill Contradicts Science

A mountain lion unlucky enough to be caught in a trap set for a bobcat. Photograph compliments of Nevada Department of Wildlife and Tom Knudson, author of RevealNews article, “America’s trapping boom relies on cruel and grisly tools.”

This January, a bill called HB0012 was introduced in the Wyoming legislature that, if passed, would allow any person with a valid hunting license to kill a mountain lion using a trap or snare. This bill is not based on valid science, and the negative consequences for mountain lions, other wildlife, Wyoming citizens, and the Wyoming Game and Fish Department are far-reaching. As a Wyoming resident and mountain lion biologist, I’m alarmed to see our legislature considering a bill that threatens the balance of nature on which our state so deeply depends.

Ostensibly, this bill was introduced to provide “additional tools” to reverse recent mule deer population declines, a valuable game species for Wyoming residents. In reality, the connection between mountain lions and mule deer population declines is tenuous at best. The Wyoming Game and Fish Department has openly shared that mule deer declines are largely the result of other factors, including habitat loss and disruption to migration corridors. It is also well accepted among wildlife biologists that deer dynamics are driven primarily by weather patterns, and resulting forage availability, not predators. In fact, a recent intensive, long term study from the Idaho Department of Fish & Game emphasized that removing mountain lions and coyotes did not provide any long-term benefit to deer populations. The researchers reported: “In conclusion, benefits of predator removal appear to be marginal and short term in southeastern Idaho and likely will not appreciably change long-term dynamics of mule deer populations in the intermountain west” (Hurley et al. 2011). (Emphasis added).

Like mule deer, mountain lions are also experiencing significant population declines in some areas; research conducted by Panthera in Teton County, Wyoming shows that mountain lion numbers north of Jackson have declined by half over the last eight years. Mountain lions in Wyoming are currently legally hunted with all legal firearms, archery equipment and trailing hounds, and these methods have proven effective in reducing mountain lion populations across the West. Introducing trapping – an imprecise method of hunting – could cripple mountain lion populations further, as well as rapidly and unexpectedly influence other wildlife populations.

The very nature of trapping is non-discriminate. Trapping consists of snares and leghold traps, including steel jaws, which often cause serious damage to animals – breaking legs, ripping skin, or completely severing limbs, via the trap or through self-mutilation. Traps deliver painful, slow deaths to wildlife. In Wyoming, it is currently illegal to kill a female mountain lion with kittens or the kittens themselves. However, a trapper cannot dictate what animal is caught, resulting in the potential maiming or killing of female mountain lions, their kittens, or federally-listed wolves, wolverines, Canada lynx, and grizzly bears. Traps may also injure people, should they stumble into one well concealed.

Mountain lion kitten against the backdrop of her mother. Photograph by Mark Elbroch / Panthera
Mountain lion kitten against the backdrop of her mother. Photograph by Mark Elbroch / Panthera

Trapping is not only imprecise in its implementation, it is also nearly impossible to track and monitor. This bill would completely undermine mountain lion management currently conducted by the Wyoming Game and Fish Department, introducing chaos to a tracking system that may not be ideal, but works. When Wyoming’s House and Senate representatives introduce legislation that threatens their own Wyoming Game & Fish Department’s ability to protect our state’s immense and singular biodiversity, something is clearly wrong.

Every year, visitors from around the globe flock to Yellowstone and Grand Teton National Parks, investing millions of dollars in Wyoming communities, in the hopes of glimpsing charismatic apex predators, like the mountain lion. As one of America’s richest wildlife resources, Wyoming can and should be a model of conservation and coexistence.

Recently, similar bills to permit mountain lion trapping came before the legislatures of New Mexico and Montana. New Mexico passed the bill into law, while Montana defeated it. The eyes of the American West are on Wyoming. It falls on us to make sustainable, scientific decisions for our state and every creature with which we share this precarious and wonderful balance that we call home.

Panthera has joined forces with the Mountain Lion Foundation to oppose HB0012. The MLF has done great work in creating a petition for those who are interested in joining us in opposing the bill–found here–signatures will be grouped by region and each will be signed to a letter sent to WY representatives on your behalf, highlighting our scientific and ethical objections of this bill.  Or if you prefer to contact Wyoming representatives directly, this link will bring you to a list of all representatives and their contact information. Thank you for your support.

Logo_BlackBackgrounds_smallLiterature cited:

Hurley, M. A., Unsworth, J. W., Zager, P., Hebblewhite, M., Garton, E. O., Montgomery, D. M., Skalski, J. R. and Maycock, C. L. (2011), Demographic response of mule deer to experimental reduction of coyotes and mountain lions in southeastern Idaho. Wildlife Monographs, 178: 1–33.

Changing Planet


Meet the Author
Mark Elbroch is Director of the Puma Program for Panthera, a US-based non-profit that conducts science and conservation action to promote wild cat conservation worldwide. He has contributed to puma research in Idaho, Colorado, California, Wyoming, Mexico, Washington and Chile. He earned his PhD at the University of California, Davis, where his dissertation research focused on puma ecology in Patagonia in the presence of endangered humeul deer. He has authored/coauthored 10 books on natural history (http://www.amazon.com/Mark-Elbroch/e/B001ILHI96) and numerous scientific articles published in peer-review journals.