Snowy mountains in Colorado with blooming wild flowers at the base.
Photo of lion warning sign in park.


Mule deer studies are planning to kill hundreds of mountain lions.

Colorado Parks and Wildlife Commission voted to approve a controversial predator control plan that would involve kill 20 to 50 percent of pumas in parts of Colorado to see whether this predator reduction will increase the mule deer population so that humans can hunt more deer. This approach is misdirected and ill-informed, as previous research has already shown that killing mountain lions to bolster ungulate numbers is not an effective tool, and that factors other than predation are limiting deer numbers.

The plan has been approved, but we may still be able to stop the killing if we act fast! Contact Governor Hickenlooper and speak out against this management plan.

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Help Stop the CPW Commission from killing Colorado's Cats!

Despite much public objection, on December 14th, 2016, the Colorado Parks and Wildlife Commission voted unanimously to approve a controversial predator management plan that would involve killing up to 50% of the mountain lions in some areas to see whether they can increase the mule deer population for human hunters to kill. Decades of previous research has already shown that killing mountain lions to increase ungulates is ineffective (Murie 1940, Cain et al. 1971, National Research Council 1997, Lee et al. 1998, Gill et al. 1999, Watkins et al. 2002, Pojar and Bowden 2004, Bright and Hervert 2005, Mosnier et al. 2008, Bishop et al. 2009, Hurley et al. 2011, Forrester and Wittmer 2013, Bergman et al. 2014, Monteith et al. 2014, Bergman et al. 2015, Mitchell et al. 2015, Prugh and Arthur 2015, Johnson et al. 2016, Treves et al. 2016, etc.).

In fact, CPW has itself found that mule deer are limited by a variety of factors including: barriers to migration, disease, doe harvest and hunting demands, declining habitat quality, habitat loss, highway mortality, predation, recreational impacts, competition with other native ungulates, and weather (U.S. Department of Agriculture 2016).

Photo of mule deer.

The following is guest Commentary by Marc Bekoff, reposted from the Huffington Post from an article published on September 15th, 2016:

The best available science is clear: in order to thrive, mule deer, elk, and bighorn sheep need adequate room to roam and plenty to eat, and not be heavily hunted. In several recent studies, researchers found that killing mountain lions (or coyotes) did not benefit mule deer because their populations were limited by other factors including habitat loss or fragmentation, hunting, poaching, fire suppression, noxious weeds, changes in forage quality, overgrazing by livestock, energy development, and changes in hydrology caused by global warming — including changes in snow pack and temperature (e.g. Forrester and Wittmer 2013; Monteith et al. 2014). Bishop et al. (2009), in their long-term Colorado-based study, found that a lack of food limited a deer population, and especially on winter ranges.

They determined that if deer had access to adequate nutrition neither mountain lions nor coyotes negatively affected the deer population. They also suggested that mountain lions selected for deer who had poor body condition, which means that mountain lions and coyotes keep herds healthier. In a follow up, Colorado-based study, Bergman et al. (2014) found that managing winter range for the deer, including conducting weed control and reseeding, benefitted deer greatly.

There are a number of factors that contribute to mule deer decline, but mountain lions are the least of them. Mule deer need habitat, food, and not heavy persecution by hunters and poachers. Thus, repeating mountain lion-killing studies over and over again is problematic and a waste of money and lives, especially if the purpose of such a "study" is so that hunters can kill more deer.

When a trophy hunter kills one mountain lion there is widespread "collateral damage"

Each year hundreds of trophy hunters pay a nominal fee to the Colorado Parks and Wildlife for the privilege of killing the state's most iconic representative of the wild: mountain lions. While Colorado Parks and Wildlife records show that trophy hunters kill approximately 400 mountain lion deaths annually, countless more die from the wake caused by trophy hunting. Hunting mountain lions disrupts their social structure and land tenure systems, which creates social chaos among them and causes even more mortalities.

It's well known that if a trophy hunter kills a female mountain lion, there is a high probability her young kittens will die from starvation or dehydration. But new research indicated that when trophy hunters remove the stable adult mountain lions from a population, it attracts young male mountain lions to these vacancies. Recall Cecil, the African lion who was famously and horrifically killed by a trophy hunter, whose young cubs were eaten by an incoming male. The same happens in mountain lion populations. Immigrating young males often kill cubs sired by the previous male so they can produce their own. In the process, however, females defending their cubs are also frequently killed. It's not just the mountain lion in the trophy hunter's crosshairs who dies. Trophy hunting causes a harmful domino effect in lion populations and there is significant and widespread "collateral damage."

The Colorado Parks and Wildlife and its Commission need to take a step back. They must allow for democratic public processes involving the greatest number of stakeholders to participate and comment. Their hearing schedule can be found here.

Join together with the Mountain Lion Foundation, the Human Society of the United States, many other environmental groups, and members of the public to fight this proposed plan! Contact Governor Hickenlooper and let him know that you are upset about the vote and ask for a change in the makeup of the commission so that it better represents the general public:

Office of the Governor
136 State Capitol Bldg
Denver, CO 80203
(303) 866-2471
(303) 866-2003 (fax)

Or contact the Commissioners and let them know that you don't agree with their decision to support the study:

Colorado Parks and Wildlife Commission
James Pribyl (303) 444-3205
John V Howard, Jr (303) 554-5885
Michelle Zimmerman (303) 881-3087
Robert William Bray (970) 729-1954
Chris Castilian (720) 929-6831
William Kane (970) 927-8232
Dale Pizel (719) 658-0269
James Vigil (719) 845-0890
Robert "Dean" Wingfield (970) 332-5471
Alexander Zipp (719) 561-8291

Graph of human-caused lion mortality in co.

Click here to view our Activist Guide...

Becoming a Mountain Lion Activist

There are lots of opportunities to take action!

Are you new to mountain lion activism? You want to change your local environment to improve it for cougars... but you don't know how to start. You may feel like you are all alone... but it takes just one person to change the attitudes and lifestyles of hundreds of others. You don't need to belong to a group. It doesn't take special skills or superhuman abilities. You just need to care enough about cougars to want to help them survive. You've already done the hard part, now let us help you with the next step.

ON AIR: Marc Bekoff on Culling Lions

11/10/15 An Audio Interview with Julie West, MLF Broadcaster

In this edition of our audio podcast ON AIR, MLF Volunteer Broadcaster Julie West interviews Marc Bekoff. Marc discusses Colorado's unscientific plan to hunt more mountain lions in the hopes it will increase deer and elk herds. The conversation goes beyond wildlife management to take a deeper look at how we view, value and treat all other animals who share this planet. Perhaps it's time we all stop and analyze the killing of animals from an ethical perspective.

Killing Mountain Lions to Grow Mule Deer

10/01/15 Guest Commentary by Marc Bekoff

Animal expert and biology professor Marc Bekoff discusses Colorado's misguided plan to kill mountain lions in the hope it will increase deer populations. Though it may seem like less predators would yield more prey, there is no science to back the state's plan. In fact, killing large numbers of mountain lions causes chaos and increases ecological problems. Please contact the Colorado Parks and Wildlife Commission and urge them to vote against this plan which would cause significant and widespread collateral damage.

Click here to open a new window and visit the agency's website...

Colorado Parks and Wildlife

Commonly abbreviated as: CPW

Bob Broscheid, Parks and Wildlife Director

Main Office:
1313 Sherman Street, 6th Floor
Denver, CO 80203

Carnivore Coordinator
Jerry Apker
0722 South Rd 1East
Monte Vista CO 81144

Please write to the director and express your concern for mountain lions in Colorados.

Thank CPW when they take steps to protect our state's mountain lions. Politely ask for policy reform and more officer training when they fall short of expectations.