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Graphic: Mule Deer

Graphic: Background Information

What is a mule deer?
Mule deer live throughout western North America from the southern Yukon to northern Mexico. "Mulies" are the most prevalent deer inhabiting the Mid-Columbia Basin. In our region, this big game animal provided meat and clothing for Native Americans long before the first European settlers arrived. Today, mule deer also are valuable for their natural beauty, which symbolizes to some our western heritage and environmental health.

Photo: Mule Deer
Mule deer are prevalent in the Mid-Columbia Basin.

What do mule deer look like?
The mule deer gets its name from its large mule-like ears, which usually are about one-quarter larger than those of the white-tailed deer. These ears help keep the deer on constant alert for signs of danger. Mulies have an obvious white rump patch and a small, rope-like white tail with a black tip. They shed their hair twice a year, producing a fine-textured tan to reddish-brown coat in summer and a coarser buff to gray in winter. Only the bucks grow antlers, which they shed each year after mating season. If you're driving through the Mid-Columbia Basin trying to spot mule deer, be on the lookout for the animal's characteristic high, stiff-legged bounce among the sagebrush. Mule deer can jump an 8-foot fence with ease, and it seems as if they are bounding on springs. This attribute enables the deer to see over vegetation and keep an eye on any approaching danger.

What are the habits of mule deer?
In our region, mule deer are most active at dawn and dusk when they venture from protective cover to feed. They spend the middle of the day bedded down in cool, secluded places. In summer, the bucks bed down in dense shade during daylight, while female deer (does) and baby deer (fawns) are more likely to rest in open areas. Mule deer are considered to be browsers rather than grazers, and thus, rely on shrubs as a primary energy source. They are ruminants and digest their food in much the same way as a cow. Although mulies can reach an impressive speed of up to 30 miles per hour, they are at their best in rough, broken country. The longest bounds (up to 28 feet in length) are made when deer descend a hill. Mule deer also are excellent swimmers. Along the Hanford Reach, female deer frequently swim out to the Columbia River islands, where they give birth to their fawns.

What about the buck's antlers?
Mule deer bucks do not use their antlers as protection from predators. Mostly, they protect themselves by rearing up and slashing out with their front hooves. Instead, bucks use their antlers to establish dominance over other bucks in a forceful pushing and shoving match. Only the strongest and most dominant males have an opportunity to mate from fall through the middle of the winter. After mating season, bucks lose their antlers when they simply drop off. When a buck has passed its prime, or food is poor, the antlers may not fully develop. Thus, antlers serve as a tool for ensuring the genetic strength of the population.

Graphic: Shrub-Steppe Logo

Graphic: Notes... "Science is constructed of facts as a house is of stones. But a collection of facts is no more a science than a heap of stones is a house." Henri Poincare

Keep in mind this fact sheet is intended to be used only as background information to support your effort to encourage inquiry-based science, which parallels the way scientists uncover knowledge and solve problems.

Graphic: Suggested Activities

1. Have students collect deer signs such as droppings, antlers, bones, and/or hair.
This collection could include pictures of tracks, urine marks, browse marks, and beds. Ask students how we know the artifacts were left behind by deer. Remind students that deer signs are a way predators or humans know a deer has been in the area. Native Americans were skilled trackers and hunters, using animal signs to guide them to their prey. If a deer trail is possible for your students to get to, have students walk the trail looking for signs.

Questions a scientist might ask: How big or heavy do you think the animal was? Which direction was the animal traveling? How many different animals were there? How old do you think the tracks are? What are the habitat requirements of mule deer? What seasonal changes do the deer go through?

2. Invite a wildlife biologist to your classroom.
Often these scientists will bring antlers they have collected in the field during their studies. Have the scientist describe the difference between horns and antlers. Have students find pictures of animals with horns and those with antlers.

3. Population Census.
Have students research ways they could conduct a mule deer population census (i.e., visual counts, pellet counts, browse survey).

4. Conduct a debate.
Conduct a debate on whether humans should continue to manage mule deer populations in the Columbia Basin. What are the pros and cons? Compare deer populations in the Columbia Basin to other areas in the United States. How are deer populations managed in these places?

Graphic: Other Resources

  1. A Guide to Animal Tracking and Behavior, D. Stokes, 1986. Little, Brown & Company, Boston, Massachusetts.
  2. I Am of This Land - Wildlife of the Hanford Site, Dan Landeen and Jeremy Crow, 1997. Western Printing, Clarkston, Washington.
  3. Shrub-Steppe Seasons: A Natural History of the Mid-Columbia Basin, Lee E. Rogers, 1995. Pacific Northwest National Laboratory, Richland, Washington. p. 56-59.
  4. The Peterson Field Guide Series: A Field Guide to the Mammals, Burt, W.H., R.P. Grossenheider, 1976. Peterson, R.A. (Ed.). Houghton Mifflin Company, Boston.

Graphic: Web sites...

  1. eNature -
  2. Mammals of Texas - Mule Deer -
  3. Mule Deer -
  4. Mule Deer -
  5. North American Deer -
  6. Smithsonian National Museum of Natural History -

Graphic: Acknowledgments Logo

Initial development and printing was funded by the Partnership for Arid Lands Stewardship. Written by: Betty Walton, Columbia Basin College. Series Editor: Georganne O'Connor; Design: WinSome Design; Printing: Eagle Printing and Graphic Design. First Printing: June 1998.

Graphic: Shrub-Steppe Ecology Series Logo


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