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COYOTES

Jeffrey S. Green
Assistant Regional Director
USDA-APHIS-Wildlife Services Lakewood, Colorado 80228

F. Robert Henderson
Extension Specialist
Animal Damage Control
Kansas State University
Manhattan, Kansas 66506-1600

Mark D. Collinge
State Director
USDA-APHIS-Wildlife Services
Boise, Idaho 83705

Identification

In body form and size, the coyote (Canis latrans) resembles a small
collie dog, with erect pointed ears, slender muzzle, and a bushy tail
(Fig. 1). Coyotes are predominantly brownish gray in color with a light
gray to cream-colored belly. Color varies greatly, however, from nearly
black to red or nearly white in some individuals and local populations.
Most have dark or black guard hairs over their back and tail. In
western states, typical adult males weigh from 25 to 45 pounds (11 to
16 kg) and females from 22 to 35 pounds (10 to 14 kg). In the East,
many coyotes are larger than their western counterparts, with males
averaging about 45 pounds (14 kg) and females about 30 pounds (13 kg).

Coyote-dog and coyote-wolf hybrids exist in some areas and may vary
greatly from typical coyotes in size, color, and appearance. Also,
coyotes in the New England states may differ in color from typical
western coyotes. Many are black, and some are reddish. These
colorations may partially be due to past hybridization with dogs and
wolves. True wolves are also present in some areas of coyote range,
particularly in Canada, Alaska, Montana, northern Minnesota, Wisconsin,
and Michigan. Relatively few wolves remain in the southern United
States and Mexico.

Range

Historically, coyotes were most common on the Great Plains of North
America. They have since extended their range from Central America to
the Arctic, including all of the United States (except Hawaii), Canada,
and Mexico.

Habitat

Many references indicate that coyotes were originally found in
relatively open habitats, particularly the grasslands and sparsely
wooded areas of the western United States. Whether or not this was
true, coyotes have adapted to and now exist in virtually every type of
habitat, arctic to tropic, in North America. Coyotes live in deserts,
swamps, tundra, grasslands, brush, dense forests, from below sea level
to high mountain ranges, and at all intermediate altitudes. High
densities of coyotes also appear in the suburbs of Los Angeles,
Pasadena, Phoenix, and other western cities.

Food Habits

Coyotes often include many items in their diet. Rabbits top the list of
their dietary components. Carrion, rodents, ungulates (usually fawns),
insects (such as grasshoppers), as well as livestock and poultry, are
also consumed. Coyotes readily eat fruits such as watermelons, berries,
and other vegetative matter when they are available. In some areas
coyotes feed on human refuse at dump sites and take pets (cats and
small dogs).

Coyotes are opportunistic and generally take prey that is the easiest
to secure. Among larger wild animals, coyotes tend to kill young,
inexperienced animals, as well as old, sick, or weakened individuals.
With domestic animals, coyotes are capable of catching and killing
healthy, young, and in some instances, adult prey. Prey selection is
based on opportunity and a myriad of behavioral cues. Strong, healthy
lambs are often taken from a flock by a coyote even though smaller,
weaker lambs are also present. Usually, the stronger lamb is on the
periphery and is more active, making it more prone to attack than a
weaker lamb that is at the center of the flock and relatively immobile.

Coyote predation on livestock is generally more severe during early
spring and summer than in winter for two reasons. First, sheep and cows
are usually under more intensive management during winter, either in
feedlots or in pastures that are close to human activity, thus reducing
the opportunity for coyotes to take livestock. Second, predators bear
young in the spring and raise them through the summer, a process that
demands increased nutritional input, for both the whelping and nursing
mother and the growing young. This increased demand corresponds to the
time when young sheep or beef calves are on pastures or rangeland and
are most vulnerable to attack. Coyote predation also may increase
during fall when young coyotes disperse from their home ranges and
establish new territories.

General Biology, Reproduction, and Behavior

Coyotes are most active at night and during early morning hours
(especially where human activity occurs), and during hot summer
weather. Where there is minimal human interference and during cool
weather, they may be active throughout the day.

Coyotes bed in sheltered areas but do not generally use dens except
when raising young. They may seek shelter underground during severe
weather or when closely pursued. Their physical abilities include good
eyesight and hearing and a keen sense of smell. Documented recoveries
from severe injuries are indicative of coyotes' physical endurance.
Although not as fleet as greyhound dogs, coyotes have been measured at
speeds of up to 40 miles per hour (64 km/hr) and can sustain slower
speeds for several miles (km).

Distemper, hepatitis, parvo virus, and mange (caused by parasitic
mites) are among the most common coyote diseases. Rabies and tularemia
also occur and may be transmitted to other animals and humans. Coyotes
harbor numerous parasites including mites, ticks, fleas, worms, and
flukes. Mortality is highest during the first year of life, and few
survive for more than 10 to 12 years in the wild. Human activity is
often the greatest single cause of coyote mortality.

Coyotes usually breed in February and March, producing litters about 9
weeks (60 to 63 days) later in April and May. Females sometimes breed
during the winter following their birth, particularly if food is
plentiful. Average litter size is 5 to 7 pups, although up to 13 in a
litter has been reported. More than one litter may be found in a single
den; at times these may be from females mated to a single male. As
noted earlier, coyotes are capable of hybridizing with dogs and wolves,
but reproductive dysynchrony and behaviors generally make it unlikely.
Hybrids are fertile, although their breeding seasons do not usually
correspond to those of coyotes.

Coyote dens are found in steep banks, rock crevices, sinkholes, and
underbrush, as well as in open areas. Usually their dens are in areas
selected for protective concealment. Den sites are typically located
less than a mile (km) from water, but may occasionally be much farther
away. Coyotes will often dig out and enlarge holes dug by smaller
burrowing animals. Dens vary from a few feet (1 m) to 50 feet (15 m)
and may have several openings.

Both adult male and female coyotes hunt and bring food to their young
for several weeks. Other adults associated with the denning pair may
also help in feeding and caring for the young. Coyotes commonly hunt as
singles or pairs; extensive travel is common in their hunting forays.
They will hunt in the same area regularly, however, if food is
plentiful. They occasionally bury food remains for later use.

Pups begin emerging from their den by 3 weeks of age, and within 2
months they follow adults to large prey or carrion. Pups normally are
weaned by 6 weeks of age and frequently are moved to larger quarters
such as dense brush patches and/or sinkholes along water courses. The
adults and pups usually remain together until late summer or fall when
pups become independent. Occasionally pups are found in groups until
the breeding season begins.

Coyotes are successful at surviving and even flourishing in the
presence of people because of their adaptable behavior and social
system. They typically display increased reproduction and immigration
in response to human-induced population reduction.

Damage and Damage Identification

Coyotes can cause damage to a variety of resources, including
livestock, poultry, and crops such as watermelons. They sometimes prey
on pets and are a threat to public health and safety when they frequent
airport runways and residential areas, and act as carriers of rabies.
Usually, the primary concern regarding coyotes is predation on
livestock, mainly sheep and lambs. Predation will be the focus of the
following discussion.

Since coyotes frequently scavenge on livestock carcasses, the mere
presence of coyote tracks or droppings near a carcass is not sufficient
evidence that predation has taken place. Other evidence around the site
and on the carcass must be carefully examined to aid in determining the
cause of death. Signs of a struggle may be evident. These may include
scrapes or drag marks on the ground, broken vegetation, or blood in
various places around the site. The quantity of sheep or calf remains
left after a kill vary widely depending on how recently the kill was
made, the size of the animal killed, the weather, and the number and
species of predators that fed on the animal.

One key in determining whether a sheep or calf was killed by a predator
is the presence or absence of subcutaneous (just under the skin)
hemorrhage at the point of attack. Bites to a dead animal will not
produce hemorrhage, but bites to a live animal will. If enough of the
sheep carcass remains, carefully skin out the neck and head to observe
tooth punctures and hemorrhage around the punctures. Talon punctures
from large birds of prey will also cause hemorrhage, but the location
of these is usually at the top of the head, neck, or back. This
procedure becomes less indicative of predation as the age of the
carcass increases or if the remains are scanty or scattered.

Coyotes, foxes, mountain lions, and bobcats usually feed on a carcass
at the flanks or behind the ribs and first consume the liver, heart,
lungs, and other viscera. Mountain lions often cover a carcass with
debris after feeding on it. Bears generally prefer meat to viscera and
often eat first the udder from lactating ewes. Eagles skin out
carcasses on larger animals and leave much of the skeleton intact. With
smaller animals such as lambs, eagles may bite off and swallow the
ribs. Feathers and "whitewash" (droppings) are usually present where an
eagle has fed.

Coyotes may kill more than one animal in a single episode, but often
will only feed on one of the animals. Coyotes typically attack sheep at
the throat, but young or inexperienced coyotes may attack any part of
the body. Coyotes usually kill calves by eating into the anus or
abdominal area.

Dogs generally do not kill sheep or calves for food and are relatively
indiscriminate in how and where they attack. Sometimes, however, it is
difficult to differentiate between dog and coyote kills without also
looking at other sign, such as size of tracks (Fig. 2) and spacing and
size of canine tooth punctures. Coyote tracks tend to be more
oval-shaped and compact than those of common dogs. Nail marks are less
prominent and the tracks tend to follow a straight line more closely
than those of dogs. The average coyote's stride at a trot is 16 to 18
inches (41 to 46 cm), which is typically longer than that of a dog of
similar size and weight. Generally, dogs attack and rip the flanks,
hind quarters, and head, and may chew ears. The sheep are sometimes
still alive but may be severely wounded.

Accurately determining whether or not predation occurred and, if so, by
what species, requires a considerable amount of knowledge and
experience. Evidence must be gathered, pieced together, and then
evaluated in light of the predators that are in the area, the time of
day, the season of the year, and numerous other factors. Sometimes even
experts are unable to confirm the cause of death, and it may be
necessary to rely on circumstantial information. For more information
on this subject, refer to the section Procedures for Evaluating
Predation on Livestock and Wildlife, in this book.

Legal Status

The status of coyotes varies depending on state and local laws. In some
states, including most western states, coyotes are classified as
predators and can be taken throughout the year whether or not they are
causing damage to livestock. In other states, coyotes may be taken only
during specific seasons and often only by specific methods, such as
trapping. Night shooting with a spotlight is usually illegal. Some
state laws allow only state or federal agents to use certain methods
(such as snares) to take coyotes. Some states have a provision for
allowing the taking of protected coyotes (usually by special permit)
when it has been documented that they are preying on livestock. In some
instances producers can apply control methods, and in others, control
must be managed by a federal or state agent. Some eastern states
consider the coyote a game animal, a furbearer, or a protected species.
foot prints of canid predators fox, dog and coyote

Fig. 2. Footprints of canid predators

Federal statutes that pertain to wildlife damage control include the
Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA), which
deals with using toxicants, and the Airborne Hunting Act, which
regulates aerial hunting.

Laws regulating coyote control are not necessarily uniform among states
or even among counties within a state, and they may change frequently.
A 1989 Supreme Court action established that it was not legal to
circumvent the laws relative to killing predators, even to protect
personal property (livestock) from predation.

Large dog

Damage Prevention and Control Methods

For managing coyote damage, a variety of control methods must be
available since no single method is effective in every situation.
Success usually involves an integrated approach, combining good
husbandry practices with effective control methods for short periods of
time. Regardless of the means used to stop damage, the focus should be
on damage prevention and control rather than elimination of coyotes. It
is neither wise nor practical to kill all coyotes. It is important to
try to prevent coyotes from killing calves or sheep for the first time.
Once a coyote has killed livestock, it will probably continue to do so
if given the opportunity. Equally important is taking action as quickly
as possible to stop coyotes from killing after they start.

Exclusion

Most coyotes readily cross over, under, or through conventional
livestock fences. A coyote's response to a fence is influenced by
various factors, including the coyote's experience and motivation for
crossing the fence. Total exclusion of all coyotes by fencing,
especially from large areas, is highly unlikely since some eventually
learn to either dig deeper or climb higher to defeat a fence. Good
fences, however, can be important in reducing predation, as well as
increasing the effectiveness of other damage control methods (such as
snares, traps, or guarding animals).

Recent developments in fencing equipment and design have made this
technique an effective and economically practical method for protecting
sheep from predation under some grazing conditions. Exclusion fencing
may be impractical in western range sheep ranching operations.

Net-Wire Fencing. Net fences in good repair will deter many coyotes
from entering a pasture. Horizontal spacing of the mesh should be less
than 6 inches (15 cm), and vertical spacing less than 4 inches (10 cm).
Digging under a fence can be discouraged by placing a barbed wire at
ground level or using a buried wire apron (often an expensive option).
The fence should be about 5 1/2 feet (1.6 m) high to discourage coyotes
from jumping over it. Climbing can usually be prevented by adding a
charged wire at the top of the fence or installing a wire overhang.

Barrier fences with wire overhangs and buried wire aprons were tested
in Oregon and found effective in keeping coyotes out of sheep pastures
(Fig. 3). The construction and materials for such fencing are usually
expensive. Therefore, fences of this type are rarely used except around
corrals, feedlots, or areas of temporary sheep confinement.


Barrier fence with wire overhang to exclude coyotes

Electric Fencing. Electric fencing, used for years to manage livestock,
has recently been revolutionized by the introduction of new energizers
and new fence designs from Australia and New Zealand. The chargers, now
also manufactured in the United States, have high output with low
impedance, are resistant to grounding, present a minimal fire hazard,
and are generally safe for livestock and humans. The fences are usually
constructed of smooth, high-tensile wire stretched to a tension of 200
to 300 pounds (90 to 135 kg). The original design of electric fences
for controlling predation consisted of multiple, alternately charged
and grounded wires, with a charged trip wire installed just above
ground level about 8 inches (20 cm) outside the main fence to
discourage digging. Many recent designs have every wire charged.

The number of spacings between wires varies considerably. A fence of 13
strands gave complete protection to sheep from coyote predation in
tests at the USDA's US Sheep Experiment Station (Fig. 4). Other designs
of fewer wires were effective in some studies, ineffective in others.

The amount of labor and installation techniques required vary with each
type of fencing. High-tensile wire fences require adequate bracing at
corners and over long spans. Electric fencing is easiest to install on
flat, even terrain. Labor to install a high-tensile electric fence may
be 40% to 50% less than for a conventional livestock fence.

Labor to keep electric fencing functional can be significant. Tension
of the wires must be maintained, excessive vegetation under the fence
must be removed to prevent grounding, damage from livestock and
wildlife must be repaired, and the charger must be checked regularly to
ensure that it is operational.

Charged wire Ground wire
High-tensile electric fence for coyote control

Ground level

Fig. 4. High-tensile, electric, antipredator fence.
modified livestock fence for coyote prevention Fig. 5. Existing
woven-wire livestock fence modified with electrified wire.

Coyotes and other predators occasionally become "trapped" inside
electric fences. These animals receive a shock as they enter the
pasture and subsequently avoid approaching the fence to escape. In some
instances the captured predator may be easy to spot and remove from the
pasture, but in others, particularly in large pastures with rough
terrain, the animal may be difficult to remove.

Electric Modification of Existing Fences. The cost to completely
replace old fences with new ones, whether conventional or electric, can
be substantial. In instances where existing fencing is in reasonably
good condition, the addition of one to several charged wires can
significantly enhance the predator-deterring ability of the fence and
its effectiveness for controlling livestock (Fig. 5). A charged trip
wire placed 6 to 8 inches (15 to 230 cm) above the ground about 8 to 10
inches (20 to 25 cm) outside the fence is often effective in preventing
coyotes from digging and crawling under. This single addition to an
existing fence is often the most effective and economical way to
fortify a fence against coyote passage.

If coyotes are climbing or jumping a fence, charged wires can be added
to the top and at various intervals. These wires should be offset
outside the fence. Fencing companies offer offset brackets to make
installation relatively simple. The number of additional wires depends
on the design of the original fence and the predicted habits of the
predators.

Portable Electric Fencing. The advent of safe, high-energy chargers has
led to the development of a variety of portable electric fences. Most
are constructed with thin strands of wire running through polyethylene
twine or ribbon, commonly called polywire or polytape. The polywire is
available in single and multiple wire rolls or as mesh fencing of
various heights. It can be quickly and easily installed to serve as a
temporary corral or to partition off pastures for controlled grazing.

Perhaps the biggest advantage of portable electric fencing is the
ability to set up temporary pens to hold livestock at night or during
other predator control activities. Portable fencing increases livestock
management options to avoid places or periods of high predation risk.
Range sheep that are not accustomed to being fenced, however, may be
difficult to contain in a portable fence.

Fencing and Predation Management. The success of various types of
fencing in keeping out predators has ranged from poor to excellent.
Density and behavior of coyotes, terrain and vegetative conditions,
availability of prey, size of pastures, season of the year, design of
the fence, quality of construction, maintenance, and other factors all
interplay in determining how effective a fence will be. Fencing is most
likely to be cost-effective where the potential for predation is high,
where there is potential for a high stocking rate, or where electric
modification of existing fences can be used.

Fencing can be effective when incorporated with other means of
predation control. For example, combined use of guarding dogs and
fencing has achieved a greater degree of success than either method
used alone. An electric fence may help keep a guarding dog in and
coyotes out of a pasture. If an occasional coyote does pass through a
fence, the guarding dog can keep it away from the livestock and alert
the producer by barking.

Fencing can also be used to concentrate predator activity at specific
places such as gateways, ravines, or other areas where the animals try
to gain access. Traps and snares can often be set at strategic places
along a fence to effectively capture predators. Smaller pastures are
easier to keep free from predators than larger ones encompassing
several square miles (km^2).

Fencing is one of the most beneficial investments in predator damage
control and livestock management where practical factors warrant its
use.

As a final note, fences can pose problems for wildlife. Barrier fences
in particular exclude not only predators, but also many other wildlife
species. This fact should be considered where fencing intersects
migration corridors for wildlife. Ungulates such as deer may attempt to
jump fences, and they occasionally become entangled in the top wires.

Cultural Methods and Habitat Modification

At the present time, there are no documented differences in the
vulnerability of various breeds of sheep to coyote or dog predation
because there has been very little research in this area. Generally,
breeds with stronger flocking behaviors are less vulnerable to
predators.

A possible cause of increased coyote predation to beef cattle calves is
the increased use of cattle dogs in herding. Cows herded by dogs may
not be as willing to defend newborn calves from coyotes as those not
accustomed to herding dogs.

Flock or Herd Health. Healthy sheep flocks and cow/calf herds have
higher reproductive rates and lower overall death losses. Coyotes often
prey on smaller lambs. Poor nutrition means weaker or smaller young,
with a resultant increased potential for predation. Ewes or cows in
good condition through proper nutrition will raise stronger young that
may be less vulnerable to coyote predation.

Record Keeping. Good record-keeping and animal identification systems
are invaluable in a livestock operation for several reasons. From the
standpoint of coyote predation, records help producers identify loss
patterns or trends to provide baseline data that will help determine
what type and amount of coyote damage control is economically feasible.
Records also aid in identifying critical problem areas that may require
attention. They may show, for example, that losses to coyotes are high
in a particular pasture in early summer, thus highlighting the need for
preventive control in that area.

Counting sheep and calves regularly is important in large pastures or
areas with heavy cover where dead livestock could remain unnoticed. It
is not unusual for producers who do not regularly count their sheep to
suffer fairly substantial losses before they realize there is a
problem. Determining with certainty whether losses were due to coyotes
or to other causes may become impossible.

Season and Location of Lambing or Calving. Both season and location of
lambing and calving can significantly affect the severity of coyote
predation on sheep or calves. The highest predation losses of sheep and
calves typically occur from late spring through September due to the
food requirements of coyote pups. In the Midwest and East, some lambing
or calving occurs between October and December, whereas in most of the
western states lambing or calving occurs between February and May. By
changing to a fall lambing or calving program, some livestock producers
have not only been able to diversify their marketing program, but have
also avoided having a large number of young animals on hand during
periods when coyote predation losses are typically highest.

Shortening lambing and calving periods by using synchronized or group
breeding may reduce predation by producing a uniform lamb or calf crop,
thus reducing exposure of small livestock to predation. Extra labor and
facilities may be necessary, however, when birthing within a
concentrated period. Some producers practice early weaning and do not
allow young to go to large pastures, thus reducing the chance of coyote
losses. This also gives orphaned and weak young a greater chance to
survive.

The average beef cattle calf production is about 78% nationwide.
First-calf heifers need human assistance to give birth to a healthy
calf about 40% of the time. Cow/calf producers who average 90% to 95%
calf crops generally check their first-calf heifers every 2 hours
during calving. Also, most good producers place first-calf heifers in
small pastures (less than 160 acres [64 ha]). When all cows are bred to
produce calves in a short, discreet (e.g. 60-day) period, production
typically increases and predation losses decrease. The birth weight of
calves born to first-calf heifers can be decreased by using
calving-ease bulls, thus reducing birthing complications that often
lead to coyote predation.

Producers who use lambing sheds or pens for raising sheep and small
pastures or paddocks for raising cattle have lower predation losses
than those who lamb or calve in large pastures or on open range. The
more human presence around sheep, the lower the predation losses.
Confining sheep entirely to buildings virtually eliminates predation
losses.

Corrals. Although predation can occur at any time, coyotes tend to kill
sheep at night. Confining sheep at night is one of the most effective
means of reducing losses to predation. Nevertheless, some coyotes and
many dogs are bold enough to enter corrals and kill sheep. A
"coyote-proof" corral is a wise investment. Coyotes are more likely to
attack sheep in unlighted corrals than in corrals with lights. Even if
the corral fence is not coyote-proof, the mere fact that the sheep are
confined reduces the risk of predation. Penning sheep at night and
turning them out at mid-morning might reduce losses. In addition,
coyotes tend to be more active and kill more sheep on foggy or rainy
days than on sunny days. Keeping the sheep penned on foggy or rainy
days may be helpful.

Aside from the benefits of livestock confinement, there are some
problems associated it. Costs of labor and materials associated with
building corrals, herding livestock, and feeding livestock must be
considered. In addition, the likelihood of increased parasite and
disease problems may inhibit adoption of confinement as a method of
reducing damage.

Carrion Removal. Removal and proper disposal of dead sheep and cattle
are important since livestock carcasses tend to attract coyotes,
habituating them to feed on livestock.

Some producers reason that coyotes are less likely to kill livestock if
there is carrion available. This may be a valid preventative measure if
an adequate supply of carrion can be maintained far away from
livestock. If a coyote becomes habituated to a diet of livestock
remains, however, it may turn to killing livestock in the absence of
carcasses. Wherever there is easily accessible carrion, coyotes seem to
gather and predation losses are higher. Conversely, where carrion is
generally not available, losses are lower. A study in Canada showed
that the removal of livestock carcasses significantly reduced
overwinter coyote populations and shifted coyote distributions out of
livestock areas.

Habitat Changes. Habitat features change in some areas, depending on
seasonal crop growth. Some cultivated fields are devoid of coyotes
during winter but provide cover during the growing season, and a
corresponding increase in predation on nearby livestock may occur.

The creation of nearly 40 million acres (16 million ha) of Conservation
Reserve Program (CRP) acres may benefit many species of wildlife,
including predators. These acres harbor prey for coyotes and foxes, and
an increase in predator populations can reasonably be predicted.
Clearing away weeds and brush from CRP areas may reduce predation
problems since predators usually use cover in their approach to
livestock. Generally, the more open the area where livestock are kept,
the less likely that coyote losses will occur. Often junk piles are
located near farmsteads. These serve as good habitat for rabbits and
other prey and may bring coyotes into close proximity with livestock,
increasing the likelihood for opportunistic coyotes to prey on
available livestock. Removing junk piles may be a good management
practice.

Pasture Selection. If sheep or beef cattle are not lambed or calved in
sheds or lots, the choice of birthing pastures should be made with
potential coyote predation problems in mind. Lambs and calves in remote
or rugged pastures are usually more vulnerable to coyote predation than
those in closer, more open, and smaller pastures. In general, a
relatively small, open, tightly fenced pasture that can be kept under
close surveillance is a good choice for birthing livestock that are
likely targets of coyotes. Past experience with predators as well as
weather and disease considerations should also serve as guides in the
selection of birthing pastures.

A factor not completely understood is that, at times, coyotes and other
predators will kill in one pasture and not in another. Therefore,
changing pastures during times of loss may reduce predation. There may

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