Mule Deer Are Valued in Montana

Diane Tipton, Montana Fish, Wildlife & Parks Statewide Information Officer

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Montana’s landscape wouldn’t be the same without the mule deer that populate the state’s flat sage-brush prairie lands of the east, rugged mountains and low riparian zones of the west and almost everywhere in-between.

Montana’s mule deer and white-tailed deer are considered "New World" deer, a group that some believe may have evolved about 5 million years ago in the forests of North America and Siberia. "Old World" deer evolved in Asia. There are about 34 species of deer worldwide.

Wildlife viewers know that deer are often easy to observe, hunters treasure them, biologists admire them, and for any doubters, Montana Fish, Wildlife & Parks can even quantify how valuable they are to us.

FWP studies show that Montana’s deer hunting season generates nearly $75 million in annual revenue for the state, at the same time that it helps to fill many families’ freezers with venison.

So what can we make of the other side of deer: the cost in highway vehicular accidents, and   the lost landscaping and garden produce?

"Mule deer are a classic example of an animal that has continuously adapted to Montana’s dynamic environment and learned to exploit it to their benefit," said Dave Pac, FWP wildlife researcher who has studied deer for decades.

Pac said the state’s urban deer have adapted to living alongside humans in some cases in exchange for safety from predators, less hunting pressure and increased access to highly nutritional forage. In other words, urban deer are just doing what well-adapted deer do—making the most of a good situation in order to optimize their reproductive success.

"Mule deer are anything but random in the way they do things," he said. "Their movements are adaptive and flexible, but structured and organized to optimize their long-term survival."

Pac has radio-collared and tracked deer over significant periods of time in an intensive FWP study of how deer use habitat, including summer and winter ranges, what they need to successfully reproduce, and a host of other issues important to successful management of mule deer populations.

Pac explained that a deer’s movement within its home range is structured around accessing food, avoiding predators, and maintaining its role in the social structure where dominant females share prime habitat with their daughters and their female offspring.   

Some deer may have large resident home ranges of one to four square miles and remain within that range winter and summer, while other migratory deer populations might winter on 300-600 acres, and then move 20 miles to locate on a summer home range that is similar or even smaller in size. Most deer migrations are in the range of five to 20 miles, to an extreme of 100 miles.

"A doe that uses the habitat to successfully rear a fawn to adulthood has put together a package of resources that worked, and that is huge," Pac said. "That doe’s offspring will mimic its mother’s choices and have a better chance of reproductive success because of it."

A doe’s female offspring will share the mother’s productive home environment, generally forming ranges adjacent to and sometimes intersecting with the matriarchs. Females retreat to especially rich spaces or "reproductive habitats" alone to have their fawns, using the extra nutrition to increase their milk supply. Once fawns begin to be weaned in late summer, small family groups reform, with does that are related and their new fawns.

"Successful use of the habitat becomes traditional and is transmitted from one generation of mule deer to the next through the long-lasting social bonds formed by these groups," Pac said.

This means that the deer on the hillside each fall, or along your route to work, are not random herds but family groups, most commonly a matriarch and her offspring. Surrounding them and ranging more widely are the males or bucks.

The story of deer, their adaptive abilities and their affinity to their social groups and to the landscape, is a story of place, a story of Montana.