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Wildlife Extension Program
Pronghorn Antelope
By Sanford D. Schemnitz Professor
Wildlife Science New Mexico State University Las Cruces,
New Mexico 88003
 Identification
The pronghorn (Antilocapra americana) is not a true
antelope but in a family by itself (Antilocapridae).
It is native only to North America. The pronghorn is
the only North American big game animal that has branched
horns, from which its name derives. Pronghorns have
true horns — derived from hair — not antlers.
The horns have an outer sheath of fused, modified hair
that covers a per- manent, bony core. Pronghorns shed
the hollow outer sheath each year in October or November
and grow a new set by July. Both bucks and does have
horns, but doe horns are shorter and more slender. Adult
pronghorns stand 3 feet (90 cm) high at the shoulders.
Bucks weigh about 110 pounds (50 kg); does weigh about
80 pounds (36 kg). Pronghorns have a bright reddish
tan coat marked with white and black. The buck has a
conspicuous black neck patch below the ears, which is
lacking on the doe. At a distance, their markings break
up the outline of their body, making them difficult
to see. Their white rump patch is enlarged and conspicuous
when they are alarmed. The flash of white serves as
a warning signal to other pronghorns and is visible
at long distances.
Range
Pronghorns currently have a scattered but widespread
distribution through out western North America (Fig.
2). In the early 1800s, when the Lewis and Clark expedition
recorded the presence of large herds of pronghorn, the
total population across North America was estimated
at 35 million. In less than 100 years, however, intensive
market hunting brought pronghorn numbers to a low of
approximately 13,000. Quick action by conservation minded
leaders saved the pronghorn from possible extinction.
In the late 1800s and  early
1900s most Great Plains state legislatures passed laws
making it unlawful to kill, ensnare, or trap pronghorns.
Pronghorns were given complete protection for nearly
50 years. In the 1940s and 1950s, limited hunting seasons
were permitted, and pronghorn sea sons have been held
ever since in most Great Plains states. Populations
have shown a notable increase in the last 2 decades.
A game management success story documents an increase
from a population low of a few bands of pronghorn in
Nebraska during the early 1900s to a current population
of about 7,000. Trapping and transplanting programs
to reestablish pronghorn populations by the state wildlife
agencies and proper management and protection have been
major factors in the pronghorn’s recovery.
Fig. 2 - range of Pronghorn in North America
Habitat
Pronghorns thrive in short and mixed grasslands and
sagebrush grasslands. They prefer rolling, open, expansive
terrain at elevations of 3,000 to 6,000 feet (900 to
1,800 m), with highest population densities in areas
receiving an average of 10 to 15 inches (25 to 38 cm)
of precipitation annually. Vegetation heights on good
pronghorn ranges average 15 inches (38 cm) with a mini
mum of 50% ground cover of mixed vegetation. Healthy
pronghorn populations are seldom found more than 3 to
4 miles (4.8 to 6.4 km) from water. Pronghorns sometimes
migrate between their summer and winter ranges. Since
they seldom jump over objects more than 3 feet (90 cm)
high, most fences stop them unless they can go under
or through them. The construction of many highways with
par allel fencing has greatly altered the m gratory
patterns of pronghorns. Woven wire fences, in particular,
are a barrier that impede pronghorn movements to water,
wintering grounds, and essential forage. Proper spacing
of barbed wire in fences (Fig. 3) is essential to allow
adequate pronghorn movement.
Fig. 3
Food Habits
Pronghorns eat a variety of plants, mostly forbs and
browse. Sagebrush often makes up a large part of their
diet. They are dainty feeders, plucking only the tender,
green shoots. Pronghorns compete with sheep for forbs,
but are often found on summer cattle ranges where cattle
eat the grasses, leaving the forbs and browse. Dietary
overlap of pronghorns with sheep and cattle was 40%
and 15%, respectively, in New Mexico. In the win ter,
pronghorns often feed in winter wheat and alfalfa fields.
General Biology, Reproduction, and Behavior
Pronghorns depend on their eyesight and speed to escape
enemies. Their eyes protrude in such a way that they
can see in a side direction. They prefer to live on
the open plains where they can see for long distances.
Pronghorns are the fastest North American big game animal
and can reach speeds of up to 60 miles per hour (96
kph). Fig. 3. Specifications for livestock fences constructed
on antelope ranges, recommended by the US Bureau of
Land Management Regional Fencing Workshop (1974).
Pronghorns are social animals, gathering in relatively
large herds. In spring, however, bucks are alone or
form small groups. Pronghorns breed during September
and October. Bucks are polygamous, collecting harems
of 7 to 10 does, which they defend from other bucks.
Bucks and does begin breeding at 15 to 16 months of
age. Usually 2 kids (young) are born 8 months after
mating. The kids are grayish brown at birth and usually
weigh 5 to 7 pounds (2.3 to 3.2 kg). Does nurse their
kids and keep them hidden until they are strong enough
to join the herd, usually at 3 weeks of age. By fall,
the kids can take care of themselves and are some- what
difficult to distinguish from adults. Pronghorns are
relatively disease- and parasite-free. Losses occur
from preda- tion, primarily coyote, and starvation during
severe winters with prolonged deep snow.
Damage
Pronghorns sometimes cause damage to grain fields, alfalfa,
and haystacks during the winter. Damage occurs from
feeding, bedding, and trampling.
Legal Status
Pronghorns have game-animal status in all of the western
states. Permits are required to trap or shoot pronghorns.
Damage Prevention and Control Methods
Exclusion
Woven wire fences of 8-inch (20-cm) mesh, 48 inches
(1.2 m) high, near agri- cultural fields will help to
curtail dam- age. Electric fences with two wires spaced
at 8 to 10 inches (20 to 25 cm) and 3 feet (90 cm) above
the ground will discourage pronghorns from entering
croplands. A single strand of electric wire painted
with molasses as an attractant and 30 to 36 inches (76
to 91 cm) above the ground will discour- age pronghorn
access.
Cultural Methods
Plant tall crops, such as corn, as a bar- rier between
rangelands and small grain fields to help reduce damage.
Alfalfa fields adjacent to rangeland are more vulnerable
and apt to suffer damage. Pronghorns often move out
of pastures that are heavily grazed by cattle to ungrazed
areas.
Frightening
Propane or acetylene exploders may provide temporary
relief from crop damage. These devices are also used
for bird damage control (see Bird Dispersal Techniques
and Supplies and Materials).
Repellents
None are registered.
Toxicants
None are registered, and poisoning pronghorns also violates
state laws that protect them as game animals.
Trapping
In areas where crop depredation and livestock competition
are severe, pronghorns can be readily herded with aircraft
into corral traps. After capture, they can be translocated
into suitable unoccupied habitat. This technique is
for use only by federal or state wildlife agencies.
Shooting
Encourage legal hunting near agricultural fields to
help curtail crop damage. Shooting permits are available
in some states to remove pronghorns that are causing
significant damage outside of the regular hunting season.
Economics of Damage and Control
Competition with livestock and occasional damage to
agricultural crops should be weighed against the economic
value of pronghorns as game animals. Landowners in Texas
and other Great Plains states often charge $200 or more
for trespass fees per hunter. Guided hunts may yield
$600 to $800 or more per animal taken. In addition,
many landowners derive aesthetic pleasure from observing
pronghorns. Some states provide economic reimbursement
for crop dam- age. In Wyoming, costs of pronghorn crop
damage on private land, including administration (for
example, salaries and travel) averaged $169,453 per
year (1987 to 1991). Similar ante- lope crop damage
costs in Colorado for the same period averaged $5,510
per year.
Acknowledgments
Figure 1 by Charles W. Schwartz, adapted from Yoakum
(1978) by Emily Oseas Routman. Figure 2 from Burt and
Grossenheider (1976), adapted by Jill Sack Johnson.
Figure 3 from the US Bureau of Land Management (1974).
For Additional Information
Kitchen, D. W., and B. W. O’Gara. 1982. Pronghorn.
Pages 960-971 in J. A. Chapman and G. A. Feldhamer,
eds. Wild mammals of North America: biology, management
and economics. The Johns Hopkins Univ. Press, Baltimore,
Maryland.
O’Gara, B. W. 1978. Antilocapra americana. Mammal.
Sp. 90:1-7.
US Bureau of Land Management. 1974. Proc. Regional
Fencing Workshop. Washington, DC. 74 pp.
Yoakum, J. D. 1978. Pronghorn. Pages 102-122 in J.
L. Schmidt and D. L. Gilbert, eds. Big game of North
America. Wildl. Manage. Inst. and Stackpole Books, Harrisburg,
Pennsylvania.
Yoakum, J. D., and B. W. O’Gara. 1992. Pronghorn
antelope: ecology and management. Wildl. Manage. Inst.
(in prep).
Yoakum, J. D., and D. E. Spalinger. 1979. American
pronghorn antelope - articles published in the Journal
of Wildlife Management 1937-1977. The Wildl. Soc., Washington,
DC. 244 pp.
Editors
Scott E. Hygnstrom Robert M. Timm Gary E. Larson
Source
PREVENTION AND CONTROL OF WILDLIFE DAMAGE — 1994
Cooperative Extension Division Institute of Agriculture
and Natural Resources University of Nebraska - Lincoln
United States Department of Agriculture Animal and Plant
Health Inspection Service Animal Damage Control Great
Plains Agricultural Council Wildlife Committee
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