Throughout the entire western United States, including the four
deserts of the American Southwest.
Mule Deer moves between various zones from the forest edges at
higher elevations to the desert floor, depending on the season.
Mule Deer have large ears that move constantly and independently, from
whence they get their name, "Mule" or "Burro Deer." They do not run as
other deer, but have a peculiar and distinctive bounding leap (stotting)
over distances up to 8 yards, with all 4 feet coming down together. In
this fashion, they can reach a speed of 35 mph for short periods.
This stocky deer with sturdy legs is 4 to 6-1/2 feet in length and 3 to
3-1/2 feet high at the shoulder. During the summer, the coat on its upper
body is yellow- or reddish-brown, while in winter more gray. The throat
patch, rump patch, inside ears and inside legs are white with lower
portions running cream to tan.
The Mule Deer is slower and less colorful than the White-tailed Deer,
but its pastel, gray-buff color provides a physical adaptation to the
desert environment which disguises it from predators like the Cougar, the
Coyote and the eagle who will swoop down on a fawn.
Another physical adaptation, its larger feet, allows the Mule Deer to
claw out waterless as much as two feet deep, which it detects with its
keen sense of smell.
Males are larger than females. The bucks' antlers, which start growth
in spring and are shed around December each year, are high and branch
forward, forking equally into 2 tines with a spread up to 4 feet.
Mule Deer have no canine teeth and, like the cow, have a multi-part
stomach, the first two chambers of which act as temporary storage bins.
Food stored here can be digested later when the deer chews its cud.
There are 2 major subspecies: the Mule Deer, with tail white above,
tipped with black; and the Black-tailed Deer, with tail black or brown
Mule Deer are active primarily in mornings, evenings and moonlit
nights. This inactivity during the heat of the day is a behavioral
adaptation to the desert environment that conserves water and keeps the
body temperature within livable limits. Sweat glands and panting also
provide evaporative cooling during hot periods.
Mule deer are browsers and eat a great variety of vegetable matter,
including fresh green leaves, twigs, lower branches of trees, and various
grasses. They are particularly fond of blackberry and raspberry vines,
grapes, mistletoe, mushrooms and ferns. They eat so carefully they can
even consume the fruit of cactus.
The mating season for Mule Deer reaches its peak in November, as
antlered stags round up females and fight for their possession. In
December, antlers are shed. Males and females mix freely while traveling
together in groups during winter months, often down to the desert
When antlers start growing again in the spring, the group breaks up.
The females go off by themselves and eventually give birth and nurse their
young; the males wander in friendly twosomes or small bands throughout the
summer months as antlers grow.
From April through June, after about a 200-day gestation period, the
doe delivers 1 to 4 young (normally 2). The fawn, colored reddish with
white spots, weighs about 6 pounds at birth. It must nurse within the
first hour and stand within the first 12 hours. During early weeks of
life, the fawn sees its mother only at mealtimes for feeding. Spots begin
to fade by the end of the first month.