CARNIVORES: Feral Dogs
Fig. 1. Feral dog, Canis
In appearance, most feral
dogs (Fig. 1) are difficult, if not impossible, to
distinguish from domestic dogs. Like domestic dogs,
feral dogs (sometimes referred to as wild or
free-ranging dogs) manifest themselves in a variety of
shapes, sizes, colors, and even breeds. McKnight (1964)
noted German shepherds, Doberman pinschers, and collies
as breeds that often become feral. Most feral dogs today
are descendants of domestic dogs gone wild, and they
often appear similar to dog breeds that are locally
The primary feature that
distinguishes feral from domestic dogs is the degree of
reliance or dependence on humans, and in some respect,
their behavior toward people. Feral dogs survive and
reproduce independently of human intervention or
assistance. While it is true that some feral dogs use
human garbage for food, others acquire their primary
subsistence by hunting and scavenging like other wild
Feral and domestic dogs
often differ markedly in their behavior toward people.
Scott and Causey (1973) based their classification of
these two types by observing the behavior of dogs while
confined in cage traps. Domestic dogs usually wagged
their tails or exhibited a calm disposition when a human
approached, whereas most feral dogs showed highly
aggressive behavior, growling, barking, and attempting
to bite. Some dogs were intermediate in their behavior
and couldn’t be classified as either feral or domestic
based solely on their reaction to humans. Since many
feral dogs have been pursued, shot at, or trapped by
people, their aggressive behavior toward humans is not
surprising. Gipson (1983) described the numerous lead
pellets imbedded under the skin of a feral dog caught in
Arkansas as a testament to its relationship with people.
Feral dogs are usually
secretive and wary of people. Thus, they are active
during dawn, dusk, and at night much like other wild
canids. They often travel in packs or groups and may
have rendezvous sites like wolves. Travel routes to and
from the gathering or den sites may be well defined.
Food scraps and other evidence of concentrated activity
may be observed at gathering sites.
The appearance of tracks
left by feral dogs varies with the size and weight of
the animal. Generally, dog tracks are rounder and show
more prominent nail marks than those of coyotes, and
they are usually larger than those of foxes. Since a
pack of feral dogs likely consists of animals in a
variety of sizes and shapes, the tracks from a pack of
dogs will be correspondingly varied, unlike the tracks
of a group of coyotes. The publication by Acorn and
Dorrance (1990) contains a comparative illustration of
Feral dogs are the most
widespread of the wild canids. They may occur wherever
people are present and permit dogs to roam free or where
people abandon unwanted dogs. Feral dogs probably occur
in all of the 50 states, Canada, and Central and South
America. They are also common in Europe, Australia,
Africa, and on several remote ocean islands, such as the
Home ranges of feral dogs
vary considerably in size and are probably influenced by
the availability of food. Dog packs that are primarily
dependent on garbage may remain in the immediate
vicinity of a dump, while other packs that depend on
livestock or wild game may forage over an area of 50
square miles (130 km2) or more.
Feral dogs are often found
in forested areas or shrublands in the vicinity of human
habitation. Some people will not tolerate feral dogs in
close proximity to human activity; thus they take
considerable effort to eliminate feral dogs in such
areas. Feral dogs may be found on lands where human
access is limited, such as military reservations and
large airports. They may also live in remote sites where
they feed on wildlife and native fruits. The only areas
that do not appear to be suitable for feral dogs are
places where food and escape cover are not available, or
where large native carnivores, particularly wolves, are
common and prey on dogs.
Like coyotes, feral dogs
have catholic diets and are best described as
opportunistic feeders. They can be efficient predators,
preying on small and large animals, including domestic
livestock. Many rely on carrion, particularly
road-killed animals, crippled waterfowl, green
vegetation, berries and other fruits, and refuse at
General Biology, Reproduction, and Behavior
Feral dogs are highly
adaptable, social carnivores. Most are about the size of
a coyote or slightly larger. Many breeds of dogs are
capable of existing in the wild, but after a few
generations of uncontrolled breeding, a generalized
mongrel tends to develop. Often it has a German shepherd
or husky-like appearance. Feral dogs on the Galapagos
Islands resemble the original introduced breeds: hounds,
pointers, and Borzoi.
Gipson (1983) suggested
that family groups of feral dogs are more highly
organized than previously believed. Pup rearing may be
shared by several members of a pack. Survival of pups
born during autumn and winter has been documented, even
in areas with harsh winter weather. Gipson found that
only one female in a pack of feral dogs studied in
Alaska gave birth during two years of study, even though
other adult females were present in the pack. The
breeding female gave birth during late September or
early October during both years. It is noteworthy that
all pups from both litters had similar color markings,
suggesting that the pups had the same father. Adult
males of different colors were present in the pack.
Nesbitt (1975) commented
on the rigid social organization of a pack of feral dogs
where nonresident dogs were excluded, including females
in estrus. In one instance, Nesbitt used three separate
female dogs in estrus as bait (dogs were chained in the
back of a corral-type trap) over a 59-day period and
captured no feral dogs. He then baited the same trap
with carrion, and a pack of feral dogs, including four
adult males, entered the trap within 1 week.
feral dogs and other wild canids can occur, but
non-synchronous estrus periods and pack behavior (that
is, excluding nonresident canids from membership in the
pack) may preclude much interbreeding.
Dens may be burrows dug in
the ground or sheltered spots under abandoned buildings
or farm machinery. Feral dogs commonly use former fox or
Damage and Damage Identification
Livestock and poultry can
be victims of harassment, injury, and death from both
domestic and feral dogs. Distinguishing between
livestock killed by domestic or feral dogs and that
killed by coyotes may be difficult since the mode of
attack can be similar. Coyotes usually attack an animal
at the throat; domestic dogs are relatively
indiscriminate in how and where they attack. Sometimes,
however, dogs kill the way coyotes do, and young and
inexperienced coyotes may attack any part of the body of
their prey as dogs would. The survival of feral dogs,
much like that of other wild canids, depends on their
ability to secure food. Therefore feral dogs are usually
adept predators. Unlike most domestic dogs, feral dogs
rely on their prey for food, and thus consume much of
what they kill. Feral dogs favor the hindquarters and
viscera (liver, spleen, heart, lungs).
When domestic dogs attack
domestic animals, they may injure or kill several, but
they seldom consume their victims. Rather, they leave
the impression that they were involved in vicious play
rather than an attempt to obtain food. The most
diagnostic characteristic of injuries caused by dogs is
usually the slashing and biting of prey animals over
much of their bodies. Wade and Bowns (1983) and Acorn
and Dorrance (1990) present a detailed pictorial and
descriptive aid to identifying predators that damage
Feral dogs may become
skilled at hunting in groups for small game such as
rabbits and hares and large game including deer and even
moose. Some wildlife managers feel that feral dogs are a
serious threat to deer, especially in areas with heavy
snows (Lowry 1978). Others have found no evidence that
feral dogs pose a significant threat to deer (Causey and
Cude 1980). Clearly, the impact of feral dogs, both on
livestock and wildlife, varies by location and is
influenced by factors such as availability of other
food, the number of dogs, and competition by other
Feral dogs may feed on
fruit crops including melons, berries, and grapes, and
native fruits such as persimmons and blackberries.
Damage to melons is similar to that caused by coyotes.
The side of a ripe melon is usually bitten open and the
Feral dogs commonly kill
house cats, and they may injure or kill domestic dogs.
In areas where people have not hunted and trapped feral
dogs, the dogs may not have developed fear of humans,
and in those instances such dogs may attack people,
especially children. This can be a serious problem in
areas where feral dogs feed at and live around garbage
dumps near human dwellings. Such situations occur most
frequently around small remote towns.
On the Galapagos Islands,
feral dogs have significantly impacted native
populations of tortoises, iguanas, and birds.
State and local laws
concerning feral and free-ranging dogs vary
considerably, but most states have some regulations.
Many states, particularly those in the west, permit
individuals to shoot dogs that are chasing or killing
game animals or livestock. State agencies or agriculture
departments usually are responsible for controlling
feral dogs in rural areas. No states consider feral dogs
to be game animals. Most cities have animal control
agents to pick up abandoned and free-ranging domestic
Prevention and Control Methods
Protect livestock and
poultry from feral and domestic dogs with
well-maintained net fences. Horizontal spacing of the
mesh should be less than 6 inches (15 cm); vertical
spacing should be less than 4 inches (10 cm). Barbed
wire at ground level or a buried wire apron will
discourage dogs from digging under the fence. The fence
should be about 6 feet (1.8 m) high to hinder animals
from jumping over. The effectiveness of fences can be
increased by adding one or more electrically charged
wires along the bottom and top. Charged wires are
positioned so that the intruding dog encounters them
before digging under or climbing over the fence.
Electric fences consisting
of up to 12 alternating ground and charged wires have
been effective at deterring dogs (Dorrance and Bourne
1980). Other configurations have also been successful
(Shelton 1984, deCalesta 1983). Electric fences must be
checked regularly to ensure that the wires are
sufficiently charged. Maintenance of fences may be
difficult in areas with drifting snow and where large
wild animals are common. Moose and bears can be
particularly destructive to electric fences.
Fencing is one of the most
beneficial investments in dealing with predator damage
and livestock management if practicality warrants its
Several visual and
auditory devices (yard lights, effigies, loud music,
pyrotechnics) have been used to frighten coyotes from
livestock pens and pastures, and are likely to be
effective with feral dogs.
Researchers at the Denver
Wildlife Research Center developed and tested a device
called the Electronic Guard, a combination strobe light
and siren that periodically activates during the night.
The noise and light have been effective in reducing
coyote predation on flocks of sheep. Similar results
could reasonably be anticipated with feral dogs.
Guarding dogs that have
been reared with livestock and trained to remain with
them can be a deterrent to depredating feral dogs (Green
and Woodruff 1991). Since a pack of feral dogs is quite
capable of killing other dogs, more than one guarding
dog may be needed where feral dogs are a threat. Donkeys
and llamas have also been used to keep dogs away from
Methyl nonyl ketone,
mostly in granular form or in liquid sprays, is widely
used to prevent urination or defecation by dogs in yards
and storage areas. Several other chemicals are
registered for repelling dogs including anise oil,
Bitrex, capsaicin, d-linonene, dried blood, essential
oils, napthalene, nicotene, Ropel, Thiram, Thymol, and
tobacco dust. These chemicals may be useful in keeping
feral dogs from establishing scent stations or relieving
themselves on selected sites, but they probably have
little value in protecting livestock or poultry.
Capsaicin (oleoresin of capsicum) and oil of anise may
be effective in protecting humans from attack by dogs.
There are no toxicants
widely used for controlling feral dogs in the United
States. The USDA-APHIS-ADC program holds a Federal
Insecticide, Fungicide, and Rodenticide Act (FIFRA)
Section 3 registration for sodium cyanide used in M-44
delivery devices. Although the product label for M-44
cyanide capsules lists wild dogs among the canids that
can be controlled when they are preying on livestock
(others include coyotes and red and gray foxes), ADC
policy prohibits using M-44s for specifically killing
dogs. Some dogs are killed by M-44s when they are being
used to kill coyotes, but dogs are not the target
animal. In addition, at least one state has a law
prohibiting ADC from using M-44s to intentionally kill
Several states hold their
own registrations for using M-44s, and their policy with
regard to feral dogs may be different from that of ADC.
Consult state and local regulations with respect to M-44
use. In all instances, M-44s can only be used by
Toxic collars containing
Compound 1080 (sodium monofluoroacetate) placed on
domestic animals may kill depredating dogs if the dogs
puncture the collar during an attack. The collars,
however, are only registered for use against coyotes.
No fumigants are
registered for the control of feral dogs.
Live traps are generally
effective in capturing feral dog pups and occasionally
adult dogs. Steel leghold traps (No. 3 or 4) are
convenient and effective for trapping wild dogs. Carrion
and scent baits used to lure coyotes to traps may be
effective in attracting feral dogs. Nontarget species or
pets inadvertently captured can be released. Caution
should be exercised when approaching a dog in a trap,
since feral dogs may be vicious when confined, and even
pet dogs may bite under those circumstances. Cable neck
snares may be set at openings in fences or along narrow
trails used by dogs. Use care when setting snares
because they may kill pets or livestock that are caught.
Aerial shooting is one of
the most efficient control techniques available for
killing feral dogs. Where a pack of damaging feral dogs
is established, it may be worthwhile to trap one or two
members of the pack, fit them with radio transmitters,
and release them. Feral dogs are highly social, and by
periodically locating the radio-tagged dogs with a radio
receiver, it is possible to locate other members of the
group. When other members of the pack are destroyed, the
radioed dogs can be located and shot. This technique has
been used effectively by the Alaska Department of Fish
and Game to eliminate packs of problem wolves.
Hunting from the ground
has been used to control feral dogs. A predator call may
lure dogs within rifle range. Establishing a shooting
blind can be helpful, especially along a trail used by
dogs, near a den, a garbage dump, or a large animal
Fencing garbage dumps,
burying garbage in sanitary landfills frequently, or
removing livestock carrion may help reduce local feral
dog populations. Locating and destroying dens,
especially when pups are present, may also be helpful.
Use catch poles to capture and restrain feral dogs. Dart
guns and jab sticks can be used to administer
tranquilizing or euthanizing agents.
The long-term solution to
most problems caused by unconfined dogs, including feral
dogs, is responsible dog ownership and effective local
dog management programs. Many depredation problems can
be solved by confining dogs to kennels or to the owner’s
property. Dog breeding must be controlled. Unwanted dogs
should be placed for adoption or destroyed rather than
abandoned, since the latter leads to the formation of
free-living, feral populations.
Dog management programs
should include the following: (1) public education about
proper care and confinement of dogs; (2) laws that
identify that dog owners are legally responsible for
damage caused by dogs; (3) laws that prohibit
abandonment of unwanted dogs and require humane disposal
of unwanted dogs; (4) holding facilities and personnel
trained to handle unwanted or nuisance dogs; and (5)
assistance by professional control specialists where
feral dogs are established.
Economics of Damage and Control
Feral dogs may destroy
livestock and poultry valued at thousands of dollars. In
such instances, the costs of controlling dogs may be
warranted. Boggess and his co-workers (1978) examined
5,800 claims of domestic livestock lost to dogs and
coyotes in Iowa between 1960 and 1974. Dogs were
considered responsible for 49% of the reported sheep
losses, 45% of the cattle losses, 66% of the swine
losses, and 82% of the poultry losses. Denny (1974)
conducted a nationwide survey of state departments of
agriculture, wildlife conservation agencies, and related
agencies to determine problems caused by unconfined
dogs. Damage to wildlife, especially deer, small game,
and birds was considered the primary problem caused by
dogs. Damage to game animals may be a serious local
problem. In view of the value placed on game animals by
hunters and other wildlife enthusiasts, local control to
benefit wild game may be economically justified. The
second most serious problem reported was damage to
Figure 1 drawn by Reneé
Lanik, University of Nebraska-Lincoln.
For Additional Information
Acorn, R. C., and M. J. Dorrance. 1990. Methods of
investigating predation of livestock. Alberta Agric.
Agdex 684-14. Edmonton, Alberta, Canada.
Barnett, B. D. 1986.
Eradication and control of feral and free-ranging dogs
in the Galapagos Islands. Proc. Vertebr. Pest Conf.
Boggess, E. K., R. D.
Andrews, and R. A. Bishop. 1978. Domestic animal losses
to coyotes and dogs in Iowa. J. Wildl. Manage.
Causey, M. K., and C. A.
Cude. 1980. Feral dog and white-tailed deer interactions
in Alabama. J. Wildl. Manage. 44:481-484.
deCalesta, D. S. 1983.
Building an electric antipredator fence. Pacific
Northwest Ext. Publ. 225:11.
Denny, R. N. 1974. The
impact of uncontrolled dogs on wildlife and livestock.
Trans. N.A. Wildl. Nat. Resour. Conf. 39:257-291.
Dorrance, M. J., and J.
Bourne. 1980. An evaluation of anti-coyote electric
fencing. J. Range Manage. 33:385-387.
Gipson, P. S. 1983.
Evaluations of behavior of feral dogs in interior
Alaska, with control implications. Vertebr. Pest Control
Manage. Mater. 4th Symp. Am. Soc. Testing Mater.
Gipson, P. S., and J. A.
Sealander. 1977. Ecological relationships of
white-tailed deer and dogs in Arkansas. Pages 3-16 in R.
L. Phillips and C. Jonkel, eds. Proc. 1975 Predator Symp.
Montana For. Conserv. Exper. Stn., Univ. Montana,
Missoula. 268 pp.
Green, J. S. 1989. Donkeys
for predation control. Proc. Eastern Wildl. Damage
Control Conf. 4:83-86.
Green, J. S., and R. A.
Woodruff. 1991. Livestock guarding dogs: protecting
sheep from predators. US Dep. Agric., Agric. Info. Bull.
No. 588. 31 pp.
Linhart, S. B., G. J.
Dasch, R. R. Johnson, J. D. Roberts, and C. J. Packham.
1992. Electronic frightening devices for reducing coyote
predation on domestic sheep: efficacy under range
conditions and operational use. Proc. Vertebr. Pest
Lowry, D. A. 1978.
Domestic dogs as predators on deer. Wildl. Soc. Bull.
McKnight, T. 1964. Feral
livestock in Anglo-America. Univ. Calif. Publ. Geogr.,
Vol. 16. Univ. Calif. Press, Berkeley.
Nesbitt, W. H. 1975.
Ecology of a feral dog pack on a wildlife refuge. Pages
391-396 in M. W. Fox, ed. The wild canids. Van Nostrand
Reinhold Co., New York.
Nesse, C. E., W. M.
Longhurst, and W. E. Howard. 1976. Predation and the
sheep industry in California 1972-1974. Univ. Calif.,
Div. Agric. Sci. Bull. 1878. 63 pp.
Scott, M. D., and K.
Causey. 1973. Ecology of feral dogs in Alabama. J. Wildl.
Shelton, M. 1984. The use
of conventional and electric fencing to reduce coyote
predation on sheep and goats. Tex. Agric. Exp. Stn. MP
US Fish and Wildlife
Service. 1979. Final environmental impact statement for
the U.S. Fish and Wildlife Service’s mammalian predator
damage management for livestock protection in the
western United States. US Dep. Inter. Washington, DC.
Wade, D. A., and J. E.
Bowns. 1983. Procedures for evaluating predation on
livestock and wildlife. Bull. No. B-1429. Texas A & M
Univ., College Station. 42 pp.
Walton, M. T., and C. A.
Field. 1989. Use of donkeys to guard sheep and goats in
Texas. Proc. Eastern Wildl. Damage Control Conf.
Scott E. Hygnstrom Robert
M. Timm Gary E. Larson
PREVENTION AND CONTROL OF
WILDLIFE DAMAGE — 1994
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