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CARNIVORES: Coyotes |
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Fig. 1. Coyote, Canis
latrans
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.
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.
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
Ground level
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 (km2).
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 seem to be a relationship
between size of pasture and predator losses, with higher
loss rates reported in larger pastures. In reality, loss
rates may not be related as much to pasture size as to
other local conditions such as slope, terrain, and human
populations. Hilly or rugged areas are typically
sparsely populated by humans and are characterized by
large pastures. These conditions are ideal for coyotes.
Sheep pastures that
contain or are adjacent to streams, creeks, and rivers
tend to have more coyote problems than pastures without
such features. Water courses serve as hunting and travel
lanes for coyotes.
Herders. Using herders
with sheep or cattle in large pastures can help reduce
predation, but there has been a trend away from herders
in recent years because of increasing costs and a
shortage of competent help. Nevertheless, tended flocks
or herds receive closer attention than untended
livestock, particularly in large pastures, and problems
can be solved before they become serious. We recommend
two herders per band of range sheep. If herders aren’t
used, daily or periodic checking of the livestock is a
good husbandry practice.
Frightening Devices and Repellents
Frightening devices are
useful for reducing losses during short periods or until
predators are removed. The devices should not be used
for long periods of time when predation is not a
problem. To avoid acclimation you can increase both the
degree and duration of effectiveness by varying the
position, appearance, duration, or frequency of the
frightening stimuli, or using them in various
combinations. Many frightening methods have been
ridiculed in one way or another; nevertheless, all of
the techniques discussed here have helped producers by
saving livestock and/or buying some time to institute
other controls.
Lights. A study involving
100 Kansas sheep producers showed that using lights
above corrals at night had the most marked effect on
losses to coyotes of all the devices examined. Out of 79
sheep killed by coyotes in corrals, only three were
killed in corrals with lights. Nearly 40% of the
producers in the study used lights over corrals. There
was some indication in the study that sheep losses to
dogs were higher in lighted corrals, but the sample size
for dog losses was small and the results inconclusive.
Most of the producers (80%) used mercury vapor lights
that automatically turned on at dusk and off at dawn.
Another advantage of
lighted corrals is that coyotes are more vulnerable when
they enter the lighted area. Coyotes often establish a
fairly predictable pattern of killing. When this happens
in a lighted corral, it is possible for a producer to
wait above or downwind of the corral and to shoot the
coyote as it enters. Red or blue lights may make the
ambush more successful since coyotes appear to be less
frightened by them than by white lights.
Revolving or flashing the
lights may enhance their effectiveness in frightening
away predators. There is some speculation that the old
oil lamps used in highway construction repelled coyotes,
presumably because of their flickering effect.
Bells and Radios. Some
sheep producers place bells on some or all of their
sheep to discourage predators. Where effects have been
measured, however, no difference in losses was detected.
Some producers use a radio
tuned to an all-night station to temporarily deter
coyotes, dogs, and other predators.
Vehicles. Parking cars or
pickups in the area where losses are occurring often
reduces predation temporarily. Effectiveness can be
improved or extended by frequently moving the vehicle to
a new location. Some producers place a replica of a
person in the vehicle when losses are occurring in the
daylight. If predators continue to kill with vehicles in
place, the vehicle serves as a comfortable blind in
which to wait and shoot offending predators.
Propane Exploders. Propane
exploders produce loud explosions at timed intervals
when a spark ignites a measured amount of propane gas.
On most models, the time between explosions can vary
from about 1 minute to 15 minutes. Their effectiveness
at frightening coyotes is usually only temporary, but it
can be increased by moving exploders to different
locations and by varying the intervals between
explosions. In general, the timer on the exploder should
be set to fire every 8 to 10 minutes, and the location
should be changed every 3 or 4 days. In cattle pastures,
these devices should be placed on rigid stands above the
livestock. Normally, the exploder should be turned on
just before dark and off at daybreak, unless coyotes are
killing livestock during daylight hours. Motion sensors
are now available and likely improve their
effectiveness, though it is still only temporary.
Exploders are best used to reduce losses until more
permanent control or preventive measures can be
implemented. In about 24 coyote depredation complaints
over a 2-year period in North Dakota, propane exploders
were judged to be successful in stopping or reducing
predation losses until offending coyotes could be
removed. “Success time” of the exploders appears to
depend a great deal on how well they are tended by the
livestock producer.
Strobe
Lights and Sirens. The USDA’s Denver Wildlife Research
Fig. 6. Electronic Guard frightening device
Center developed a
frightening device called the Electronic Guard (EG)
(Fig. 6). The EG consists of a strobe light and siren
controlled by a variable interval timer that is
activated at night with a photoelectric cell. In tests
conducted in fenced pastures, predation was reduced by
about 89%. The device is used in Kansas and other states
to protect cows/calves from coyote predation. Most
research on the effectiveness of this device, however,
has been done on sheep operations. Suggestions for using
the unit differ for pastured sheep and range operations.
To use the EG in fenced
pastures (farm flocks):
Place EGs above the ground
on fence posts, trees, or T-posts so they can be heard
and seen at greater distances and to prevent livestock
from damaging them. Position EGs so that rain water
cannot enter them and cause a malfunction. Locate EGs so
that light can enter the photocell port or window. If
positioned in deep shade, they may not turn on or off at
the desired times. The number of EGs used to protect
sheep in fenced pastures depends on pasture size,
terrain features, and the amount and height of
vegetation in or around the pasture. In general, at
least two units should be used in small (20 to 30 acres
[8 to 12 ha]), level, short-grass pastures. Three to
four units should be used in larger (40 to 100 acres [16
to 40 ha]), hilly, tall grass, or wooded pastures. Don’t
use EGs in pastures larger than about 100 acres (40 ha)
because their effective range is limited. The device
could be useful in larger pastures when placed near
areas where sheep congregate and bed at night. EGs
should be placed on high spots, where kills have been
found, at the edge of wooded areas, near or on
bedgrounds, or near suspected coyote travelways. They
should be moved to different locations every 10 to 14
days to reduce the likelihood of coyotes getting used to
them To use the EG in open range (herded or range
sheep):
The number of EGs used
will depend on the number of sheep in the band and the
size of the bedground. Four units should be used to
protect bands of 1,000 ewes and their lambs. When
possible, place one EG in the center of the bedground
and the other three around the edge of the bedground.
Try to place the units on coyote travelways. EGs should
be placed on high points, ridge tops, edges of
clearings, or on high rocks or outcroppings. Hang the
devices on tree limbs 5 to 7 feet (1.5 to 2.1 m) above
ground level. If used above timberline or in treeless
areas, hang them from a tripod of poles. Herders who bed
their sheep tightly will have better results than those
who allow sheep to bed over large areas. Sheep that are
bedded about 200 yards (166 m) or less in diameter, or
are spread out not more than 200 to 400 yards (166 to
332 m) along a ridge top, can usually be protected with
EGs. Repellents. The notion of repelling coyotes from
sheep or calves is appealing, and during the 1970s,
university and government researchers tested a wide
variety of potentially repellent chemical compounds on
sheep. Both olfactory (smell) and gustatory (taste)
repellents were examined. The underlying objective was
to find a compound that, when applied to sheep, would
prevent coyotes from killing them. Tests were conducted
with various prey species including rabbits, chickens,
and sheep. Some repellents were applied by dipping
target animals in them, others were sprayed on, and some
were applied in neck collars or ear tags.
Coyotes rely heavily on
visual cues while stalking, chasing, and killing their
prey. Taste and smell are of lesser importance in
actually making the kill. These factors may in part
account for the fact that the repellent compounds were
not able to consistently prevent coyotes from killing,
although some of the repellents were obviously offensive
to coyotes and prevented them from consuming the killed
prey. Several compounds were tested on sheep under field
conditions, but none appeared to offer significant,
prolonged protection.
If an effective chemical
repellent were to be found, the obstacles in bringing it
to industry use would be significant. The compound would
not only need to be effective, but also persistent
enough to withstand weathering while posing no undue
risk to the sheep, other animals, or the environment. It
would also have to withstand the rigorous Environmental
Protection Agency (EPA) approval process.
High-frequency sound has
also been tested as a repellent for coyotes, but the
results were no more encouraging than for chemical
repellents. Coyotes, like dogs, responded to particular
sound frequencies and showed some aversion to sounds
broadcast within one foot (30 cm) of their ear.
Researchers, however, were unable to broadcast the sound
a sufficient distance to test the effects under field
conditions.
Aversive Conditioning. The
objective of aversive conditioning is to feed a coyote a
preylike bait laced with an aversive agent that causes
the coyote to become ill, resulting in subsequent
avoidance of the prey. Most of the research on this
technique has involved the use of lithium chloride, a
salt, as the aversive agent.
Aversive conditioning is
well documented for averting rodents from food sources,
but significant problems must be overcome before the
method can be used to reduce coyote predation on sheep.
Coyotes must be induced to eat sheeplike baits that have
been treated with the aversive chemical. The chemical
must cause sufficient discomfort, such as vomiting, to
cause coyotes to avoid other baits. Furthermore, the
avoidance must be transferred to live sheep and must
persist long enough without reinforcement for the method
to offer realistic protection to sheep.
To date, pen and field
tests with aversive conditioning have yielded
conflicting and inconclusive results. It does not appear
that aversive conditioning is effective in reducing
predation, but additional field tests would be useful.
Guarding
Animals.
Livestock Guarding Dogs. A
livestock guarding dog is one that generally stays with
sheep or cattle without harming them and aggressively
repels predators. Its protective behaviors are largely
instinctive, but proper rearing plays a part. Breeds
most commonly used today include the Great Pyrenees,
Komondor, Anatolian Shepherd, and Akbash Dog (Fig. 7).
Other Old World breeds used to a lesser degree include
Maremma, Sharplaninetz, and Kuvasz. Crossbreeds are also
used.
The characteristics of
each sheep operation will dictate the number of dogs
required for effective protection from predators. If
predators are scarce, one dog is sufficient for most
fenced pasture operations. Range operations often use
two dogs per band of sheep. The performance of
individual dogs will differ based on age and experience.
The size, topography, and habitat of the pasture or
range must also be considered. Relatively flat, open
areas can be adequately covered by one dog. When brush,
timber, ravines, and hills are in the pasture, several
dogs may be required, particularly if the sheep are
scattered. Sheep that flock and form a cohesive unit,
especially at night, can be protected by one dog more
effectively than sheep that are continually scattered
and bedded in a number of locations.
Fig. 7. Livestock guarding
dog (Akbash dog)
The goal with a new puppy
is to channel its natural instincts to produce a mature
guardian dog with the desired characteristics. This is
best accomplished by early and continued association
with sheep to produce a bond between the dog and sheep.
The optimum time to acquire a pup is between 7 and 8
weeks of age. The pup should be separated from litter
mates and placed with sheep, preferably lambs, in a pen
or corral from which it can’t escape. This socialization
period should continue with daily checks from the
producer until the pup is about 16 weeks old. Daily
checks don’t necessarily include petting the pup. The
primary bond should be between the dog and the sheep,
not between the dog and humans. The owner, however,
should be able to catch and handle the dog to administer
health care or to manage the livestock. At about 4
months, the pup can be released into a larger pasture to
mingle with the other sheep.
A guarding dog will likely
include peripheral areas in its patrolling. Some have
been known to chase vehicles and wildlife and threaten
children and cyclists. These activities should be
discouraged. Neighbors should be alerted to the
possibility that the dog may roam onto their property
and that some predator control devices such as traps,
snares, and M-44s present a danger to it. Many counties
enforce stringent laws regarding owner responsibility
for damage done by roaming dogs. It is in the best
interests of the owner, dog, and community to train the
dog to stay in its designated area.
The use of guarding dogs
does not eliminate the need for other predation control
actions. They should, however, be compatible with the
dog’s behavior. Toxicants (including some insecticides
and rodenticides) used to control various pest species
can be extremely hazardous to dogs and are therefore not
compatible with the use of guarding dogs.
The M-44 is particularly
hazardous to dogs. Some people have successfully trained
their dogs to avoid M-44s by allowing the dog to set off
an M-44 filled with pepper or by rigging the device to a
rat trap. The unpleasant experience may teach the dog to
avoid M-44s, but the method is not fool-proof—one error
by the dog, and the result is usually fatal. With the
exception of toxic collars, which are not legal in all
states, toxicants should not be used in areas where
guarding dogs are working unless the dog is chained or
confined while the control takes place.
Dogs caught in a steel
trap set for predators are rarely injured seriously if
they are found and released within a reasonable period
of time. If snares and traps are used where dogs are
working, the producer should: (1) encourage the use of
sets and devices that are likely not to injure the dog
if it is caught, and (2) know where traps and snares are
set so they can be checked if a dog is missing. Aerial
hunting, as well as calling and shooting coyotes, should
pose no threat to guarding dogs. Ensuring the safety of
the dog is largely the producer’s responsibility.
Dogs may be viewed as a
first line of defense against predation in sheep and
cow/calf operations in some cases. Their effectiveness
can be enhanced by good livestock management and by
eliminating predators with suitable removal techniques.
Donkeys. Although the
research has not focused on donkeys as it has on
guarding dogs, they are gaining in popularity as
protectors of sheep and goat flocks in the United
States. A recent survey showed that in Texas alone, over
2,400 of the 11,000 sheep and goat producers had used
donkeys as guardians.
The terms donkey and burro
are synonymous (the Spanish translation of donkey is
burro) and are used interchangeably. Donkeys are
generally docile to people, but they seem to have an
inherent dislike of dogs and other canids, including
coyotes and foxes. The typical response of a donkey to
an intruding canid may include braying, bared teeth, a
running attack, kicking, and biting. Most likely it is
acting out of aggression toward the intruder rather than
to protect the sheep. There is little information on a
donkey’s effectiveness with noncanid predators such as
bears, mountain lions, bobcats, or birds of prey.
Reported success of
donkeys in reducing predation is highly variable.
Improper husbandry or rearing practices and unrealistic
expectations probably account for many failures. Donkeys
are significantly cheaper to obtain and care for than
guarding dogs, and they are probably less prone to
accidental death and premature mortality than dogs. They
may provide a longer period of useful life than a
guarding dog, and they can be used with relative safety
in conjunction with snares, traps, M-44s, and toxic
collars.
Researchers and livestock
producers have identified several key points to consider
when using a donkey for predation control:
Use only a jenny or a
gelded jack. Intact jacks are too aggressive and may
injure livestock. Some jennies and geldings may also
injure livestock. Select donkeys from medium-sized
stock. Use only one donkey per group of sheep. The
exception may be a jenny with a foal. When two or more
adult donkeys are together or with a horse, they usually
stay together, not necessarily near the sheep. Also
avoid using donkeys in adjacent pastures since they may
socialize across the fence and ignore the sheep. Allow
about 4 to 6 weeks for a naive donkey to bond to the
sheep. Stronger bonding may occur when a donkey is
raised from birth with sheep. Avoid feeds or supplements
containing monensin or lasolacid. They are poisonous to
donkeys. Remove the donkey during lambing, particularly
if lambing in confinement, to avoid injuries to lambs or
disruption of the lamb-ewe bond. Test a new donkey’s
response to canids by challenging it with a dog in a pen
or small pasture. Discard donkeys that don’t show overt
aggression to an intruding dog. Use donkeys in smaller
(less than 600 acres [240 ha]), relatively open pastures
with not more than 200 to 300 head of livestock. Large
pastures with rough terrain and vegetation and widely
scattered livestock lessen the effectiveness of a
donkey. Llamas. Like donkeys, llamas have an inherent
dislike of canids, and a growing number of livestock
producers are successfully using llamas to protect their
sheep. A recent study of 145 ranches where guard llamas
were used to protect sheep revealed that average losses
of sheep to predators decreased from 26 to 8 per year
after llamas were employed. Eighty percent of the
ranchers surveyed were “very satisfied” or “satisfied”
with their llamas. Llamas reportedly bond with sheep
within hours and offer advantages over guarding dogs
similar to those described for donkeys.
Other Animals. USDA’s
Agricultural Research Service tested the bonding of
sheep to cattle as a method of protecting sheep from
coyote predation. There was clearly some protection
afforded the sheep that remained near cattle. Whether
this protection resulted from direct action by the
cattle or by the coyotes’ response to a novel stimulus
is uncertain. Later studies with goats, sheep, and
cattle confirmed that when either goats or sheep
remained near cattle, they were protected from predation
by coyotes. Conversely, goats or sheep that grazed apart
from cattle, even those that were bonded, were readily
preyed on by coyotes.
There are currently no
research data available on the ideal ratio of cattle to
sheep, the breeds of cattle, age of cattle most likely
to be used successfully, or on the size of bonded groups
to obtain maximum protection from predation.
Multispecies grazing offers many advantages for optimum
utilization of forage, and though additional study and
experience is needed, it may also be a tool for coyote
damage control.
Any animal that displays
aggressive behavior toward intruding coyotes may offer
some benefit in deterring predation. Other types of
animals reportedly used for predation control include
goats, mules, and ostriches. Coyotes in particular are
suspicious of novel stimuli. This behavior is most
likely the primary reason that many frightening tactics
show at least temporary effectiveness.
Toxicants
Pesticides have
historically been an important component in an
integrated approach to controlling coyote damage, but
their use is extremely restricted today by federal and
state laws. All pesticides used in the United States
must be registered with the EPA under the provisions of
FIFRA and must be used in accordance with label
directions. Increasingly restrictive regulations
implemented by EPA under the authority of FIFRA, the
National Environmental Policy Act (NEPA), presidential
order, and the Endangered Species Act have resulted in
the near elimination of toxicants legally available for
predator damage control.
The only toxicants
currently registered for mammalian predator damage
control are sodium cyanide, used in the M-44 ejector
device, and Compound 1080 (sodium monofluoroacetate),
for use in the livestock protection collar. These
toxicants are Restricted Use Pesticides and may be used
only by certified pesticide applicators. Information on
registration status and availability of these products
in individual states may be obtained from the respective
state’s department of agriculture.
Sodium Cyanide in the
M-44. The M-44 is a spring-activated device used to
expel sodium cyanide into an animal’s mouth. It is
currently registered by EPA for use by trained personnel
in the control of depredating coyotes, foxes, and dogs.
The M-44 consists of a
capsule holder wrapped in an absorbent material, an
ejector mechanism, a capsule containing approximately
0.9 grams of a powdered sodium cyanide mixture, and a 5-
to 7-inch (15- to 18-cm) hollow stake (Fig. 8). For most
effective use, set M-44s in locations similar to those
for good trap sets. Drive the hollow stake into the
ground. Cock the ejector unit and secure it in the
stake. Screw the wrapped capsule holder containing the
cyanide capsule onto the ejector unit, and apply fetid
meat bait to the capsule holder. Coyotes attracted by
the bait will try to bite the baited capsule holder.
When the M-44 is pulled, the
Fig. 8. The M-44 device consists of the (a) base,
(b) ejector, (c) capsule
holder, and (d) cyanide-containing plastic capsule.
spring-activated plunger
propels sodium cyanide into the animal’s mouth,
resulting in death within a few seconds.
The M-44 is very selective
for canids because of the attractants used and the
unique requirement that the device be triggered by
pulling on it. While the use of traps or snares may
present a hazard to livestock, M-44s can be used with
relative safety in pastures where livestock are present.
Although not recommended, they can also be used in the
presence of livestock guarding dogs if the dogs are
first successfully conditioned to avoid the devices.
This can be done by allowing them to pull an M-44 loaded
with pepper. An additional advantage of M-44s over traps
is their ability to remain effective during rain, snow,
and freezing conditions.
While M-44s can be used
effectively as part of an integrated damage control
program, they do have several disadvantages. Because
canids are less responsive to food-type baits during
warm weather when natural foods are usually abundant,
M-44s are not as effective during warmer months as they
are in cooler weather. M-44s are subject to a variety of
mechanical malfunctions, but these problems can be
minimized if a regular maintenance schedule is followed.
A further disadvantage is the tendency for the cyanide
in the capsules to absorb moisture over time and to
cake, becoming ineffective. Maximum effectiveness of
M-44s is hampered by the requirement to follow 26 use
restrictions established by the EPA in the interest of
human and environmental safety. The M-44 is not
registered for use in all states, and in those where it
is registered, the state may impose additional use
restrictions. A formal training program is required
before use of M-44s. Some states allow its use only by
federal ADC specialists, whereas other states may allow
M-44s to be used by trained and certified livestock
producers.
1080 Livestock Protection
Collar.
The livestock protection
collar (LP collar or toxic collar) is a relatively new
tool used to selectively kill coyotes that attack sheep
or goats. Collars are placed on sheep or goats that are
pastured where coyotes are likely to attack. Each collar
contains a small quantity (300 mg) of Compound 1080
solution. The collars do not attract coyotes, but
because of their design and position on the throat, most
attacking coyotes will puncture the collar and ingest a
lethal amount of the toxicant. Unlike sodium cyanide,
1080 is slow-acting, and a coyote ingesting the toxicant
will not exhibit symptoms or die for several hours. As a
result, sheep or goats that are attacked are usually
killed. The collar is registered only for use against
coyotes and may be placed only on sheep or goats.
The LP collar must be used
in conjunction with specific sheep and goat husbandry
practices to be most effective. Coyote attacks must be
directed or targeted at collared livestock. This may be
accomplished by temporarily placing a “target” flock of
perhaps 20 to 50 collared lambs or kids and their
uncollared mothers in a pasture where coyote predation
is likely to occur, while removing other sheep or goats
from that vicinity. In situations where LP collars have
been used and found ineffective, the common cause of
failure has been poor or ineffective targeting. It is
difficult to ensure effective targeting if depredations
are occurring infrequently. In most instances, only a
high and regular frequency of depredations will justify
spending the time, effort, and money necessary to become
trained and certified, purchase collars, and use them
properly.
The outstanding advantage
in using the LP collar is its selectivity in eliminating
individual coyotes that are responsible for killing
livestock. The collar may also be useful in removing
depredating coyotes that have eluded other means of
control. Disadvantages include the cost of collars
(approximately $20 each) and livestock that must be
sacrificed, more intensive management practices, and the
costs and inconvenience of complying with use
restrictions, including requirements for training,
certification, and record keeping. One use restriction
limits the collars to use in fenced pastures only. They
cannot be used to protect sheep on open range. Also,
collars are not widely available, because they are
registered for use in only a few states.
Fumigants
Carbon monoxide is an
effective burrow fumigant recently re-registered by the
EPA. Gas cartridges, which contain 65% sodium nitrate
and 35% charcoal, produce carbon monoxide, carbon
dioxide, and other noxious gases when ignited. They were
registered by the EPA in 1981 for control of coyotes in
dens only. This is the only fumigant currently
registered for this purpose.
Trapping
There are many effective
methods for trapping coyotes, and success can be
enhanced by considering several key points. Coyotes
learn from past events that were unpleasant or
frightening, and they often avoid such events in the
future. In spring and summer, most coyotes limit their
movements to a small area, but in late summer, fall, and
winter they may roam over a larger area. Coyotes follow
regular paths and crossways, and they prefer high hills
or knolls from which they can view the terrain. They
establish regular scent posts along their paths, and
they depend on their ears, nose, and eyes to sense
danger.
The following describes
one method of trapping that has proven effective for
many beginners.
Items Needed to Set a
Coyote Trap:
-
One 5-gallon (19-l)
plastic bucket to carry equipment.
-
Two No. 3 or No. 4
traps per set.
-
One 18-to 24-inch
(46-to 61-cm) stake for holding both traps in place.
-
Straight claw hammer
to dig a hole in the ground for trap placement and
to pound the stake into the ground.
-
Leather gloves to
protect fingers while digging the trap bed.
-
Cloth (or canvas) feed
sack to kneel on while digging a trap bed and
pounding the stake.
-
Roll of plastic
sandwich bags to cover and prevent soil from getting
under the pan of the trap.
-
Screen sifter for
sifting soil over the traps.
-
Rib bone for leveling
off soil over the traps once they are set in place
and covered.
-
Bottle of coyote urine
to attract the coyote to the set (keep urine away
from other equipment).
Locating the Set. Coyotes
travel where walking is easy, such as along old roads,
and they have preferred places to travel, hunt, rest,
howl, and roam. Do not set traps directly in a trail but
to one side where coyotes may stop, such as on a
hilltop, near a gate, or where cover changes. Make the
set on level ground to ensure that the coyote walks
across level ground to it.
Good locations for a set
are often indicated by coyote tracks. The following are
good locations on most farms and ranches for setting
traps: high hills and saddles in high hills; near
isolated land features or isolated bales of hay; trail
junctions, fences, and stream crossings; pasture roads,
livestock trails, waterways, game trails, and dry or
shallow creek beds; near pond dams, field borders, field
corners, groves of trees, and eroded gullies; sites near
animal carcasses, bone or brush piles; and under rim
rocks.
Making the Set. Place
three to five trap sets near the area where coyotes have
killed livestock.
-
First, observe the
area where the losses are occurring and look for
tracks and droppings to determine the species
responsible. Study the paths used by predators. If
you have 4 hours to spend setting traps, spend at
least 3 of them looking for coyote sign.
-
Decide where to place
the trap sets. Always place them in an open, flat
area because of wind currents, dispersion of scent,
and visibility. Never place traps uphill or downhill
from the coyote’s expected path of approach.
-
Look for open places
where coyote tracks indicate that the animal milled
around or stopped. Place the set upwind from the
path (or site of coyote activity) so the prevailing
wind will carry the scent across the area of
expected coyote activity.
-
Choose a level spot as
close as possible to, but not directly on, the
coyote’s path. The coyote’s approach should never be
over dry leaves, tall grass, stones, sticks, weeds,
or rough ground. Make each set where the coyote has
clear visibility as it approaches.
-
Place the set using
two No. 3 traps with a cold-shut chain repair link
affixed to the top of a steel stake. The link should
swivel around the stake top. The stake should be at
least 18 inches (46 cm) long, or longer if the soil
is loose. Use two stakes set at an angle to each
other if the soil will not hold with a single stake.
Figures 9 through 29
illustrate the procedures for making a set.
Fig. 9. A piece of canvas, about 3 feet x 6 feet, used
as a kneeling cloth, makes preparing the trap site much
easier.
Fig 20. Take out or add
soil until the trap pan and jaws are about 1/2 inch
below the level of the surrounding ground. Build a ridge
for the jaw opposite the trigger to sit on. On the side
of the trap that has the trigger, place soil under the
trap pan cover on either side of the trigger to hold the
pan cover up tight against the bottom of the jaws.
Fig 21. Stretch the pan cover tightly across the pan and
under the jaws. Pan and jaws should be level and flat.
In cold weather, plastic can be placed under the trap.
Place plastic baggies on each spring and mix table salt
with dry soil or peat moss to cover the trap. Set the
other trap as shown above. Place the pan cover so that
the dog or trigger can move upward without binding it
in. Anything that slows the action of the trap can cause
a miss or a toe hold.
Fig. 23. The trap should
be set about 1/4 inch below the level of the surrounding
ground. The set must look natural. The soil around the
trap and over the springs, chains, and stake should be
packed to the same firmness as the ground the coyote
walks on in its approach to the set. Only soft soil
should be directly over the trap pan within the set jaw
area. Use a curved stick, brush, or rib bone to level
soil over the trap.
Always bury the traps and stake in the ground using dry,
finely sifted soil. One of the most difficult aspects of
using traps is trapping when the ground is frozen,
muddy, wet, or damp. If the weather is expected to turn
cold and/or wet, you should use one or a combination of
the following materials in which to set and cover the
traps: Canadian sphagnum peat moss, very dry soil, dry
manure, buckwheat hulls, or finely chopped hay. A
mixture of one part table salt or calcium chloride with
three parts dry soil will prevent the soil from freezing
over the trap. When using peat moss or other dry, fluffy
material, cover the material with a thin layer of dry
soil mixed with 1/4 teaspoon of table salt. This will
blend the set with the surrounding soil and prevent the
wind from blowing peat moss away from the trap. As an
alternative, traps could be set in a bed of dry soil
placed over the snow or frozen ground.
Guiding Coyote Footsteps.
Use a few strategically placed dirt clods, sticks, small
rocks, or stickers around the set to guide the coyote’s
foot to the traps. Coyotes will tend to avoid the
obstacles and place their feet in bare areas. Do not use
this method to the extent that the set looks unnatural.
Care of Coyote Traps. New
traps can be used to trap coyotes, but better results
may be obtained by using traps that have been dyed.
Dyeing traps helps prevent rust and removes odors. Wood
chips or crystals for dyeing traps are available from
trapping supply outlets. Some trappers also wax their
traps to prevent them from rusting and to extend the
life of the traps.
Inevitably, rusting will
occur when traps are in use. It does not harm the traps,
but after their continued use the rust often will slow
the action of the trap and cause it to miss a coyote.
Traps also become contaminated with skunk musk,
gasoline, oil, blood, or other odors. It is important
that traps be clean and in good working condition.
Rusted traps should be cleaned with a wire brush to
ensure that the trigger and pan work freely. Check the
chain links for open links. File the triggers and
receivers to eliminate all rounded edges. Make any
adjustments necessary so that the pan will sit level and
the trap perform smoothly.
Size of Traps for Coyotes.
There are many suitable traps for catching coyotes. Both
the No. 3 and No. 4 are good choices. Many trappers
prefer a No. 3 coilspring round-jawed off-set trap. It
is a good idea to use superweld kinkless chain. The
length of chain varies depending on whether the trap is
staked or a drag is used. A longer chain should be used
with a drag. The off-set jaws are designed to reduce
broken foot bones, which can allow the coyote to escape
by wriggling out of the trap. Traps with coil springs
are good coyote traps, but they require more upkeep than
a double long-spring trap. The type and size of trap may
be regulated in each state. Body gripping traps are
dangerous and illegal in some states for catching
coyotes. When pet dogs might be present, use a
padded-jaw No. 3 double coilspring trap.
While additional testing
needs to be conducted, results of research to reduce
injury using padded-jaw traps have been encouraging. In
tests with No. 3 Soft-Catch® coilsprings, No. 3 NM
longsprings, and No. 4 Newhouse longsprings, capture
rates for coyotes were 95%, 100%, and 100%,
respectively. Soft-Catch traps caused the least visible
injury to captured coyotes.
Anchoring Traps. Chain
swivels are necessary for trapping coyotes. One swivel
at the stake, one in the middle of the chain, and one at
the trap are recommended. Drags (Fig. 30) instead of
stakes can be used where there is an abundance of brush
or trees or where the ground is too rocky to use a
stake. Use a long chain (5 feet [1.5 m] or more) on a
drag.
Lures and Scents. Coyotes
are interested in and may be attracted to odors in their
environment. Commercially available lures and scents or
natural odors such as fresh coyote, dog, or cat
droppings or urine may produce good results. Coyote
urine works the best.
Problems in Trapping
Coyotes.
A great deal of experience
is required to effectively trap coyotes. Trapping by
experienced or untrained people may serve to educate
coyotes, making them very difficult to catch, even by
experienced trappers. Coyotes, however, exhibit
individualized patterns of behavior. Many, but not all,
coyotes become trap-shy after being caught and then
escaping from a trap. There is a record of one coyote
having been caught eight times in the same set. Some
coyotes require considerably more time and thought to
trap than others. With unlimited time, a person could
trap almost any coyote.
If a coyote digs up or
springs a trap without getting caught, reset the trap in
the same place. Then carefully set one or two traps near
the first set. Use gloves and be careful to hide the
traps. Changing scents or using various tricks, such as
a lone feather as a visual attraction near a set, or a
ticking clock in a dirt hole set as an audible
attraction, may help in trying to catch wary coyotes.
Resetting Traps and
Checking Trap Sets. Once a coyote is caught at a set,
reset the trap in the same place. The odor and
disturbance at the set where a coyote has been caught
will often attract other coyotes. Sometimes other
coyotes will approach but not enter the circle where the
coyote was caught. If signs indicate that this has
happened, move the trap set outside of the circle. Leave
all sets out for at least 2 weeks before moving the
traps to a new location. Check the traps once every 24
hours, preferably in the morning around 9 or 10 o’clock.
Reapply the scent every 4 days, using 8 to 10 drops of
coyote urine.
Human Scent and Coyote
Trapping. Minimize human scent around trap sets as much
as possible.
Fig. 30. Trapping drag
If traps are being set in
warm months, make sure the trapper has recently bathed,
has clean clothes, and is not sweating. Leave no
unnecessary foreign odors, such as cigarette butts or
gum wrappers, near the set. Wear clean gloves and rubber
footwear while setting traps. A landowner may have an
advantage over a stranger who comes to set traps since
the coyotes are acquainted with the landowner’s scent
and expect him/her to be there. Coyotes have been known
to leave an area after encountering an unfamiliar human
scent.
Because of human scent,
coyotes are more difficult to catch with traps in wet or
humid weather. Wear gloves, wax traps, and take other
precautionary measures in areas where humans are not
commonly present, where wet weather conditions are
common, and where coyotes have been trapped for several
years and have learned to avoid traps.
Killing a Trapped Coyote.
A coyote will make its most desperate attempt to get out
of the trap as a person approaches. As soon as you get
within a few feet (m) of the coyote, check to see that
the trap has a firm hold on the coyote’s foot. If so,
shoot the coyote in the head, with a .22 caliber weapon.
It is often a good idea to reset the trap in the same
place. The blood from the coyote will not necessarily
harm the set as long as it is not on the trap or on the
soil over the reset traps. Reset the trap regardless of
the species of animal captured, skunks included.
Draw Stations. Draw
stations are natural areas or places set up
intentionally to draw coyotes to a particular location.
For example, the straw and cleanings from a chicken
house can be placed in an area where coyote tracks are
found. Traps can then be set around the edges of the
straw. Areas around carcasses or parts of animals, such
as a cow’s head, are good places to set traps. Wire the
carcass to a stake driven into the ground and out of
sight. Once coyotes start feeding, set traps 30 to 60
feet (9 to 18 m) upwind from the carcasses or draw
station. Never set traps very close to carcasses because
nontarget animals such as vultures, eagles, hawks,
skunks, and opossums will be caught. If sheep graze in
an area where traps are set, cover the traps with a disc
blade or brush during the day and uncover them at night
when the sheep are penned.
Opposition to Traps.
Opposition to foothold traps is based primarily on two
objections: (1) a lack of selectivity for the animal
which the trap is set for and (2) foot injury sustained
by the captured animal. Trap pan tension devices such as
sticks, forked twigs, springs, and sponges placed under
the trap pan have been used for many years to reduce
captures of nontarget species. Many coyote traps have an
adjustable pan tension screw. One study evaluated two
pan tension devices. Preliminary results indicated that
the use of either device could exclude nearly 90% of the
gray foxes, swift foxes, striped skunks, opossums, and
jackrabbits that stepped on traps, as compared with 24%
on average for unequipped traps. A variety of other
species were excluded at even higher rates. Some coyotes
were also excluded, but because more traps remained
functional, the net result appeared to be an increase in
coyote trapping efficiency. Advances in trap design,
including off-set jaws and padded-jaw traps, have
increased the humaneness of foothold traps. Traps should
be checked once or twice each day to minimize the length
of time that an animal must remain in a trap.
Fig. 33. Setting the snare
Fig. 34. Fastening the snare to the stake
Snares
Snaring is the technique
of setting a steel-cable loop in an animal’s path to
capture it by the neck, body, or leg. Snares usually
consist of a 2.5- to 10foot (0.75- to 3.0-m) long piece
of galvanized aircraft cable containing a slide lock
that forms a loop in the cable (Fig. 31). On short
snares, a swivel to prevent twisting and breaking the
cable is attached to the end of the cable opposite the
loop. On longer snares, swivels can be located near the
middle of the cable and at one end.
Snares offer several
advantages over steel foothold traps. They are
lightweight, compact, simple in function, affected
little by weather, easy to set, low in cost, and offer a
high degree of human safety. In a south Texas study,
snares were 10 times more selective over steel foothold
traps for target species of coyotes and bobcats. Snares,
however, can be a greater hazard than traps to
livestock. Recent research has produced deer stops and
break-away or relaxing locks that have significantly
improved snare specificity.
Preparation of Snares. New
commercial snares and extension cables can be cleaned by
boiling each dozen snares in a pan or bucket of water
with 4 tablespoons (16 gm) of baking soda for one hour.
The snares will turn a dull gray after being removed
from this bath and hung up to dry outdoors. Darken
snares by boiling them in brown logwood crystals and
dye. After boiling, snares should be kept clean of
foreign odors. Wear clean gloves when handling and
setting snares.
How to Set Snares.
Snares designed to capture predators by the neck or leg
are set directly in the animal’s path of movement and
are held in place using various techniques. One support
that works particularly well can be constructed from a
36-inch (0.9-m) piece of 12-gauge galvanized or 9-gauge
soft wire. Form a V bend in the support wire, about 4
inches (10 cm) from the end, and drive the wire into the
ground with a notched rod (Fig. 32) to prevent the
support from moving in the wind. Wrap the snare around
the support about three times and hold it in place with
a U bend formed in the upper end of the snare support.
Bend the snare cable upward slightly, just inside the
lock, to ensure that the snare loop is not closed by the
wind (Fig. 33).
Snares should be attached
to a solid object so that captured animals cannot escape
(Fig. 34). A steel 1/2-inch (1.3- cm) diameter rebar, 24
to 30 inches (61 to 72 cm) long (depending on soil
hardness), makes a good anchor for coyotes and smaller
predators. Attach snares to the rebar with a strong
swivel to prevent tangling and breaking. A lead cable
that is at least as strong as the snare cable can be
used to attach short snares to the rebar stake. Avoid
using 9-gauge (0.38-cm) wire or several strands of
14-gauge (0.21-cm) wire to anchor snares to a rebar
stake because they may bend back and forth, crystallize,
and break. When used for coyotes, snares also can be
secured to a dead tree limb that is at least 6 inches
(15 cm) in diameter and 6 feet (2 m) long.
Snares set in holes under
woven-wire fences can be held in place about 1 to 2
inches (2.5 to 5 cm) from the fence with the snare
support system (Fig. 35). The snare should be set far
enough away from the fence to prevent the lock from
catching on the bottom wire of the fence. The bottom of
the loop should be about 2 inches (5 cm) above the
bottom of the hole. The snares can be anchored to the
heavy-gauge wire on the bottom of the fence. Two strands
of baling wire or S hooks can be used to fasten the
snare to the bottom wire.
If there is a chance of
accidentally catching a pet dog, a leg snare set is
recommended (Fig. 36). Set a small loop about 5 inches
(13 cm) or less to one side of the opening, and set the
bottom of the loop on the ground. When a coyote goes
under a fence, it places both front feet firmly on the
ground, and sticks its head just under the bottom wire.
Once its head is past the bottom wire, the coyote begins
to raise its head. The idea is to set the leg snare so
that one front foot will pass through the snare.
Snares are usually set in
the form of a round or oval loop. In a trail set (Fig.
37), a round loop that is 12 inches (30 cm) in diameter
can form an oval loop that is about 14 inches (36 cm)
high and 10 inches (25 cm) wide. Use a 5/64- or
3/32-inch (0.2- or 0.24-cm) diameter galvanized aircraft
cable for snaring coyotes. Varying round loop diameters
and heights above ground is recommended when snaring
coyotes (Table 1). The loop size in a hole in a fence
should vary depending upon the size of the hole.
Where to Set Snares.
Animals usually follow the easiest route through heavy
cover. These routes, which generally consist of trails,
are excellent locations to snare predators. Snares are
effective along trails leading to draw stations. Some
effective locations for snaring coyotes include: (1)
along trails in thickets or heavy vegetation leading to
a carcass, (2) on trails under fences, (3) on livestock
trails in vacant pastures, (4) in the bottoms of
ravines, and 5) on narrow paths inside weeds or brush.
Trails can be created by driving on weeds or stubble
with a pickup, by walking in snow, or by mowing a trail
through weeds or grass with a weed eater.
Regulations for Snaring.
Snares are not legal in all states. Where snares are
legal, most states have regulations which require that
snares be visually inspected every 24 hours. Snares
should be checked early in the morning to increase the
probability of releasing nontarget animals unharmed.
Methods to Avoid Capturing
Nontarget Animals. Sites where snares are set should be
carefully selected to avoid capturing nontarget animals.
Avoid setting snares: (1) in pastures with livestock,
(2) within 25 yards (23 m) of animal carcasses (to
prevent capturing birds of prey and other scavengers),
(3) within major deer, elk, or antelope wintering areas
(these big game animals are much less susceptible to
foothold traps), (4) on any trails being used by
livestock, deer, elk, and other nontarget animals
(attract predators away from these trails with specific
baits and lures), (5) under fences where livestock,
antelope, deer, or nontarget dogs are using the “crawl
space,” and (6) where people can readily view captured
animals.
Fig. 37. Trail snare set
Use a short snare cable to
reduce injuries where accidentally captured dogs might
jump over a fence or a tree branch. Also avoid using
entangling devices (attachments that increase the chance
of killing the snared animal) where dogs might be
captured. Use the lightest snare lock (breakaway lock)
possible to capture the desired animal. If livestock,
deer, elk, or antelope are captured by a leg, they can
usually break a light lock but may be held by heavy
locks. Record the location and number of snares on a map
so they can be found, and remove all snares when damage
stops or when they cannot be checked frequently.
Shooting
Shooting coyotes is legal
in many situations, and it often ranks high among the
choices for removing a predator. Safety, however, is a
critical factor that in some circumstances may preclude
the use of firearms (for example, local laws may
prohibit shooting, or neighbors may be too close).
For shooting coyotes, a
medium-powered bolt-action rifle fitted with a scope is
recommended. The .223 Remington, .22-250, .220 Swift, or
the .243 Winchester are all capable of killing a coyote
up to a distance of 250 yards (225 m). Since coyotes are
able to detect human scent, the shooter should take a
stand downwind from where the coyote will likely
approach. An elevated location where the lighting works
to the shooter’s advantage is a good choice. If
predators are killing sheep in the daytime, construct a
comfortable blind at a vantage point in the pasture
where the killing has occurred. Whenever possible, rest
the rifle on a solid support while aiming. A homemade
shooting stick will improve accuracy over shooting
freehand.
A shotgun, preferably a
12-gauge semi-automatic, can be used for shooting at
short range (less than 50 yards [45 m]). Often it is
advisable to have both a 12-gauge shotgun and a scoped
rifle available. Copper-coated (BB) lead shot, No. 4
buckshot (lead), and in newer shotguns, the larger-sized
steel shot works well for killing coyotes.
Shooting From Ground
Vehicles.
Shooting from vehicles
(snowmobiles, motorcycles, and pickups) in open, flat
prairie country can be effective and provide immediate
results. Under most circumstances, however, this method
is not practical as it requires keen driving skills, is
dangerous, and is illegal in most states.
Calling and Shooting
Coyotes.
Coyotes may respond to
predator calls. Calling, like other methods of predation
control, should be used sparingly and only when needed.
Coyotes can be called at any time of the day although
the first couple of hours after dawn and the last few
hours before darkness are usually best. Call in areas
where there are signs of coyotes, such as tracks or
droppings.
In some situations,
coyotes can be located by listening to their howling at
sundown and sunrise. Some hunters use sirens to elicit
howls from coyotes. Often a voice imitation of a coyote
howl works as well. Coyotes often come to a howl without
howling back, so the prudent hunter is always ready to
shoot.
Hunting at Night. Not many
people have witnessed predators killing livestock
because it usually occurs at night, away from human
activity. As stated previously, calling and shooting
predators at night is illegal in many states. Where
legal, however, hunting at night with the use of
artificial lights may be effective. Red or blue light
tends to spook predators less readily than white light
does. Calling without the use of artificial lights is
effective only with snow cover and the light of a full
moon.
Aerial Hunting. The use of
aircraft for shooting coyotes is strictly regulated by
the provisions of the Airborne Hunting Act and is
allowed only under special permit in states where legal.
Aerial hunting is selective and allows taking only the
target species. Although it is costly, it may be one of
the most cost-effective methods of reducing predator
damage when all factors are considered. It is often the
best method where conditions are right for removing
depredating animals that have successfully evaded
traditional ground control methods such as trapping.
Fixed-wing aerial hunting
is limited primarily to open areas with little
vegetative cover. The greater maneuverability of
helicopters makes them more useful for hunting in areas
of brush, scattered timber, and rugged terrain.
Although aerial hunting
can be conducted over bare ground, it is most effective
where there is deep snow cover. Animals are more visible
against a background of snow and are much less mobile in
their attempts to avoid the aircraft. Under optimal
conditions of clear, sunny skies and fresh snow cover,
much of the hunting can be accomplished by searching for
and following fresh coyote tracks. Aerial hunting
success can be increased when conducted with the
assistance of a ground crew. Before the plane arrives, a
ground crew can locate coyotes in the hunting area by
eliciting howls with a siren, a mouth-blown howler call,
or a voice howl. Two-way radio communication allows the
ground crew to direct the aircraft toward the sound of
the coyotes, thus reducing hunting time.
Aerial hunting is not
recommended for, nor undertaken by, most livestock
producers because of the special skills required of both
pilot and gunner and the danger inherent with the
low-level flight. Although weather, terrain, and state
laws limit the application of this method, it can often
provide a prompt resolution to depredation problems.
Denning
Predation can frequently
be resolved by locating coyote dens and removing the
pups and/or the adults responsible for depredations.
Denning may also be warranted as a preventive control
strategy if coyote predation has historically and
consistently occurred in a particular area during the
lambing season.
Breeding pairs of coyotes
are extremely territorial. They vigorously defend their
territories against other canine intruders. Coyotes
often den year after year in the same general location.
If a particular denning pair of coyotes has a history of
existing with and not preying on livestock, it may be to
the producer’s advantage to leave them alone. Their
removal will open up a territory that may become
occupied with coyotes that are more likely to prey on
livestock.
Although tracking a coyote
from a livestock kill back to its den requires skill and
persistence, it is probably the most foolproof method to
locate the den of the offending animals. If tracking is
not feasible because of poor tracking conditions or lack
of the required skills, there are alternatives that may
be used.
Coyotes will usually howl
in response to a howl from another coyote near their
den. One or both adult coyotes will often be near the
den between 7:30 to 9:00 a.m. A response can be elicited
by voice howling, blowing a coyote howler call, or
broadcasting recorded calls from a tape player. It is
usually best to wait 30 minutes to 1 hour between howls
because the same coyotes may not respond again within
that period.
Once the approximate
location of a den is determined, careful planning is
required to ensure the best chance of immediately
removing the adult coyotes. The hunter should approach
the den unseen and downwind to within calling distance,
armed with a high powered rifle and/or repeating shotgun
loaded with heavy shot. A call that imitates the whines
or yelps of a coyote pup can be very effective under
these circumstances, especially when used in conjunction
with a dog to act as a decoy. A small-to medium-sized
dog moving in the vicinity of the den gives the coyotes
something to focus on and reduces the likelihood that
the hunter will be detected. The sounds of a pup in
distress along with the sight of a dog so near the den
will cause most coyotes to display highly aggressive
behavior, frequently chasing the dog back to within
close proximity of the hunter.
After the adults are
removed, the pups can be killed by fumigating the den
with a gas cartridge registered for this purpose, or the
pups can be dug out by hand. If attempts to shoot one or
both adults are unsuccessful, the chances of trapping or
snaring them are improved if the pups are left alive and
confined in the den. This can be accomplished by driving
stakes 2 inches (5 cm) apart down through the den
entrance. Carefully place blind sets in the den trails
or at the den mound. Capture will often result when the
adults return to investigate the area. If the adults are
not captured within a reasonable period of time, the
pups should be destroyed. Removal of the pups is often
effective in stopping predation even if the adult
coyotes are not removed.
An airplane can be used
very effectively to locate coyote dens when depredations
occur in spring or early summer in open prairies or
sagebrush terrain. Early morning hours provide the best
light conditions for locating adult animals near the den
site or as they return from hunting. The low angle light
reflects on the coyote and provides good contrast with
the surrounding vegetation and soil. Actual den sign,
however, shows up better during the middle of the day
with light coming from directly overhead. Dens are most
easily located after the pups have begun venturing
outside. The pups soon trample down the vegetation
around the den, making the site more visible from the
air. If aerial shooting is legal, it is often possible
to remove the adults and pups in one operation. In open
terrain, landings can often be made within walking
distance of the den.
Although denning requires
special skills, training, and often considerable time,
the advantages can be significant. A cost-benefit
analysis conducted during one study determined that the
cost to remove a den of depredating coyotes could be
recovered if only 3.6 lambs were saved. In the same
study, the average number of lambs killed by each
depredating pair of coyotes was
4.9 per week. While these
findings indicate that denning could be cost effective
after only a few days, the benefits actually continue in
most instances for the duration of the season. Denning
can be very selective for the offending animals and can
resolve some depredation problems at relatively low
cost.
Hunting with Dogs. Several
breeds are generally known as trailing hounds, including
Walkers, Julys, redbones, blueticks, black and tans,
Plott hounds, and English fox hounds. Trail hounds
follow the scent left by a predator and run it to tree
or bay it on the ground. Coyotes are seldom caught and
killed by trail hounds. In most instances, trail hounds
are used in combination with sight hounds. The trail
hounds run coyotes into the open, and then sight hounds
are released to capture the fleeing coyote. More
commonly, coyotes are shot as they run from the pack of
hounds. Sight hounds, generally greyhounds or Russian
wolf hounds, are used in open prairie country to run
coyotes down and kill them.
Economics of Damage and
Control Sheep numbers in the United States have declined
about 80% from 1942 to 1976 (Gee et al. 1977). Former
sheep producers reported that the principal reasons for
leaving the sheep industry included high predation
losses, low lamb and wool prices, a shortage of good
hired labor, and the producer’s age.
The US Fish and Wildlife
Service (1978) estimated the economic impact of coyote
predation on producers with predator problems, on
producers without predator problems, and on consumers
during 1977. They used an average lamb loss rate of 4%
(267,000 lambs) and a ewe loss rate of 1.5% (125,000
ewes) to estimate an economic loss of $19 million to
producers from coyote predation in the 17 western
states. The reduced number of sheep and lambs resulted
in a higher market price, which benefited producers by
$6 million. The net impact of coyote predation on sheep
producers was a loss of $13 million, and the impact on
consumers was $4 million in additional costs. The
General Accounting Office (GAO 1990) estimated that
coyotes in 17 western states killed sheep and lambs
valued at $18 million in 1989. The National Agricultural
Statistical Service (NASS 1991) reported that sheep and
lamb losses to coyotes in the United States were valued
at $18.3 million in 1990.
The US Fish and Wildlife
Service (1978) reported calf losses between birth and
weaning to coyotes across the United States at 0.4%,
with predation decreasing to nearly zero by weaning
time. Dorrance (1982) reported that coyotes were
responsible for 16% of the 1,520 confirmed predation
losses of cattle in Alberta from 1974 to 1978. Coyote
predation on calves caused producers with coyote
problems across the United States to lose an estimated
$20 million. However, because of the greater price
flexibility of beef compared with sheep, the reduction
in the number of beef calves marketed (estimated at
0.4%, or 115,000 fewer calves) resulted in a higher
price, which benefited beef producers by $81 million.
The net impact of the reduced supply of beef as a result
of coyote predation was a gain of $61 million to beef
producers, but it cost consumers an additional $98
million in higher prices for beef, resulting in an
overall loss of $37 million. NASS (1992) reported that
cattle and calf losses to coyotes in the United States
were valued at $24.3 million in 1991.
Coyote predation also can
cause substantial losses of domestic goats. In three
studies in Texas, where an estimated 1.1 million goats
(about 90% of the goats in the United States) are raised
(Scrivner et al. 1985), predators were reported to take
18.1% of the adults and 33.9% of the kids (Pearson
1986). NASS (1991) reported that goat losses to coyotes
in the United States were valued at $5.7 million in
1990.
Pearson (1986) stated that
predators, particularly coyotes, accounted for losses of
hundreds of chickens and turkeys in the 14 western
states. In one study, Andelt and Gipson (1979) reported
that between June 4 and August 31, 1976, a mated pair of
coyotes apparently killed 268 domestic turkeys in
Nebraska valued at $938.
Although the average value
of livestock losses to coyotes reflected the overall
impact on producers, it did not reflect the severity of
losses to some individuals. Balser (1964) and Gee et al.
(1977) indicated that coyote predation is much more
serious for some producers than others. Most sheep
producers suffer no or minor predator losses, whereas
20% to 25% of the producers suffer losses that are
significantly higher than the average (US Fish Wildl.
Serv. 1978). These losses can drive producers out of
business because of low profit margins. Nonfatal
injuries and harassment of livestock by coyotes also can
result in reduced weight gain and subsequent reductions
in profit.
Acknowledgments
Much of the information
and several of the figures for this chapter were adapted
from the SID Sheep Production Handbook, Predator Damage
Control chapter, published by the American Sheep
Industry Association, Inc. (1990) and various
publications authored by
F. R. Henderson, J. S.
Green, W. F. Andelt, G. E. Connolly, and D. A. Wade.
The section on economics
of damage and control was adapted from Andelt (1987).
Figure 1 by Emily Oseas
Routman.
Figure 6 adapted from a
USDA-APHIS-ADC illustration by Renee Lanik, University
of Nebraska-Lincoln.
For Additional Information
Alberta Agriculture. 1990. Methods of investigating
predation of livestock. Alberta Agric., Crop Prot.
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Video
Tapes
Video tape, VHS.
“Livestock Guarding Dogs, Protecting Sheep From
Coyotes.” US Dep. Agric., An. Plant Health Inspect. Serv.,
An. Damage Control.
Video tape, VHS. “How to
Call a Coyote.” Kansas State Univ., Coop. Ext. Serv.
Manhattan.
Video tape VHS. “How to
Snare a Coyote.” Kansas State Univ. Coop. Ext. Serv.,
Manhattan.
Video tape, VHS. “A Matter
of Perspective.” Texas A&M Coop. Ext. Serv. San Angelo.
Video tape, VHS. “How to
Trap a Coyote.” Colorado State Univ. Coop. Ext. Serv.,
Fort Collins.
Editors
Scott E. Hygnstrom Robert
M. Timm Gary E. Larson
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
01/12/2007
Special
thanks to:
Clemson University
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