LAST EDITED ON Nov-04-10 AT 11:12AM (MST)[p]I have wondered for some time what effect mountain lions have on our mule deer population so I did some basic research and this is what I found. According to the DWR, there are approximately 2,500 cougars in the State of Utah. The Utah Cougar Management Plan contains two separate population estimates. The first study is based upon unit populations and it estimates that there are between 2,528 and 2,936 cougars. The second study is based upon mean cougar densities and total occupied cougar habitat and it estimates that there are 2,927 cougars in the state. (Utah Cougar Management Plan p. 8.) Based upon these two studies, I think it is safe to say that there are between 2,000 and 3,000 cougars in the State of Utah.
The next question is how many deer to 2,500 cougars kill in a given year. Most of us have probably heard the saying that ?a single cougar will kill on average one deer a week or 50+ deer in a year.? Although I have heard that statistic many times, I wanted to see if there was any scientific data to support it. What I found after reading several studies is that in Western states, such as Utah, mule deer make up 60-80% of a cougar?s diet throughout year. They also eat rabbits and hares, rodents, porcupines, skunks, coyotes, and, occasionally, domestic stock. (Currior, M. J. P. 1983. Felis Concolor. Mammal. Species No. 200) One of the most often cited scientific studies conducted in Idaho showed that the average cougar killed one mule deer per week or fifty deer per year. (Hornocker, M.G. 1970. An analysis of mountain lion predation upon mule deer and elk in the Idaho Primitive Area)
Based upon these numbers, it seems one could reasonably conclude that the approximately 2,500 cougars in the State of Utah may kill up to 125,000 in a year. Now these numbers seem fairly high given that we only have approximately 300,000 deer in the state. However, I would not doubt that cougars kill upwards of 100,000 deer a year. That is a huge number when you consider that we as hunters only harvest an average of about 30,000 deer a year. That means that cougars probably kill at least three times as many deer as hunters harvest in a given year.
Now, whenever someone comments on the toll that cougars take on our mule deer herds, the houndsman usually come out of the woodwork and tell us that the cougar populations are at all time lows, that we are killing more cougars now than ever, that there are no mature cats left and that cougars do not kill that many deer. I am certainly not a wildlife biologist but have done my best to find some of the premier studies on the issue and this is what the experts are saying. At a time when we are considering drastic cuts in mule deer tags and turning the whole state into limited entry units, perhaps we should take a more serious look at the impact cougars have on mule deer herds.
Hawkeye
P.S. ? For those of you that think cougars only prey on the sick and weak, please watch the following video:
Hawkeye
Browning A-Bolt 300 Win Mag
Winchester Apex .50 Cal
Mathews Drenalin LD