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CARNIVORES: Skunks |
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Identification
The skunk, a member of the
weasel family, is represented by four species in North
America. The skunk has short, stocky legs and
proportionately large feet equipped with well-developed
claws that enable it to be very adept at digging.
The striped skunk (Fig. 1)
is characterized by prominent, lateral white stripes
that run down its back. Its fur is otherwise jet black.
Striped skunks are the most abundant of the four
species. The body of the striped skunk is about the size
of an ordinary house cat (up to 29 inches [74 cm] long
and weighing about 8 pounds [3.6 kg] ). The spotted
skunk (Fig. 1) is smaller (up to 21 inches [54 cm] long
and weighing about 2.2 pounds [1 kg]), more weasel-like,
and is readily distinguishable by white spots and short,
broken white stripes in a dense jet-black coat.
The hooded skunk (Mephitis
macroura) is identified by hair on the neck that is
spread out into a ruff. It is 28 inches (71 cm) long and
weighs the same as the striped skunk. It has an
extremely long tail, as long as the head and body
combined. The back and tail may be all white, or nearly
all black, with two white side stripes. The hog-nosed
skunk (Conepatus leucontus) has a long snout that is
hairless for about 1 inch (2.5 cm) at the top. It is 26
inches (66 cm) long and weighs 4 pounds (1.8 kg). Its
entire back and tail are white and the lower sides and
belly are black. Skunks have the ability to discharge
nauseating musk from the anal glands and are capable of
several discharges, not just one.
Range
The
striped skunk is common throughout the United States and
Canada (Fig. 2a). Spotted skunks are uncommon in some
areas, but distributed throughout most of the United
States and northern Mexico (Fig 2b) The hooded skunk and
the hog-nosed skunk are much less common than striped
and spotted skunks. Hooded skunks are limited to
southwestern New Mexico and western Texas. The hog-nosed
skunk is found in southern Colorado, central and
southern New Mexico, the southern half of Texas, and
northern Mexico.
Fig. 2a. Range of the
striped skunk in North America. Fig. 2b. Range of the
spotted skunk in North America.
General Biology, Reproduction, and Behavior
Adult skunks begin
breeding in late February. Yearling females (born in the
preceding year) mate in late March. Gestation usually
lasts 7 to 10 weeks. Older females bear young during the
first part of May, while yearling females bear young in
early June. There is usually only 1 litter annually.
Litters commonly consist of 4 to 6 young, but may have
from 2 to 16. Younger or smaller females have smaller
litters than older or larger females. The young stay
with the female until fall. Both sexes mature by the
following spring. The age potential for a skunk is about
10 years, but few live beyond 3 years in the wild.
The
normal home range of the skunk is l/2 to 2 miles (2 to 5
km) in diameter. During the breeding season, a male may
travel 4 to 5 miles (6.4 to 8 km) each night.
Skunks are dormant for
about a month during the coldest part of winter. They
may den together in winter for warmth, but generally are
not sociable. They are nocturnal in habit, rather
slow-moving and deliberate, and have great confidence in
defending themselves against other animals.
Habitat
Skunks inhabit clearings,
pastures, and open lands bordering forests. On prairies,
skunks seek cover in the thickets and timber fringes
along streams. They establish dens in hollow logs or may
climb trees and use hollow limbs.
Food Habits
Skunks eat plant and
animal foods in about equal amounts during fall and
winter. They eat considerably more animal matter during
spring and summer when insects, their preferred food,
are more available. Grasshoppers, beetles, and crickets
are the adult insects most often taken. Field and house
mice are regular and important items in the skunk diet,
particularly in winter. Rats, cottontail rabbits, and
other small mammals are taken when other food is scarce.
Damage and Damage Identification
Skunks become a nuisance
when their burrowing and feeding habits conflict with
humans. They may burrow under porches or buildings by
entering foundation openings. Garbage or refuse left
outdoors may be disturbed by skunks. Skunks may damage
beehives by attempting to feed on bees. Occasionally,
they feed on corn, eating only the lower ears. If the
cornstalk is knocked over, however, raccoons are more
likely the cause of damage. Damage to the upper ears of
corn is indicative of birds, deer, or squirrels. Skunks
dig holes in lawns, golf courses, and gardens to search
for insect grubs found in the soil. Digging normally
appears as small, 3- to 4-inch (7- to 10-cm) cone-shaped
holes or patches of upturned earth. Several other
animals, including domestic dogs, also dig in lawns.
Skunks
occasionally kill poultry and eat eggs. They normally do
not climb fences to get to poultry. By contrast, rats,
weasels, mink, and raccoons regularly climb fences. If
skunks gain access, they will normally feed on the eggs
and occasionally kill one or two fowl. Eggs usually are
opened on one end with the edges crushed inward.
Weasels, mink, dogs and raccoons usually kill several
chickens or ducks at a time. Dogs will often severely
mutilate poultry. Tracks may be used to identify the
animal causing damage. Both the hind and forefeet of
skunks have five toes. In some cases, the fifth toe may
not be obvious. Claw marks are usually visible, but the
heels of the forefeet normally are not. The hindfeet
tracks are approximately 2 1/2 inches long (6.3 cm)
(Fig. 3). Skunk droppings can often be identified by the
undigested insect parts they contain. Droppings are 1/4
to 1/2 inch (6 to 13 mm) in diameter and 1 to 2 inches
(2.5 to 5 cm) long.
Odor is not always a
reliable indicator of the presence or absence of skunks.
Sometimes dogs, cats, or other animals that have been
sprayed by skunks move under houses and make owners
mistakenly think skunks are present.
Rabies may be carried by
skunks on occasion. Skunks are the primary carriers of
rabies in the Midwest. When rabies outbreaks occur, the
ease with which rabid animals can be contacted
increases. Therefore, rabid skunks are prime vectors for
the spread of the virus. Avoid overly aggressive skunks
that approach without hesitation. Any skunk showing
abnormal behavior, such as daytime activity, may be
rabid and should be treated with caution. Report
suspicious behavior to local animal control authorities.
Legal Status
Striped skunks are not
protected by law in most states, but the spotted skunk
is fully protected in some. Legal status and licensing
requirements vary. Check with state wildlife officials
before removing any skunks.
Damage
Prevention and Control Methods
Exclusion
Keep skunks from denning
under buildings by sealing off all foundation openings.
Cover all openings with wire mesh, sheet metal, or
concrete. Bury fencing 1 1/2 to 2 feet (0.4 to 0.6 m)
where skunks can gain access by digging. Seal all
ground-level openings into poultry buildings and close
doors at night. Poultry yards and coops without
subsurface foundations may be fenced with 3-foot (1-m)
wire mesh fencing. Bury the lowest foot (0.3 m) of
fencing with the bottom 6 inches (15.2 cm) bent outward
from the yard or building. Skunks can be excluded from
window wells or similar pits with mesh fencing. Place
beehives on stands 3 feet (1 m) high. It may be
necessary to install aluminum guards around the bases of
hives if skunks attempt to climb the supports. Skunks,
however, normally do not climb. Use tight-fit-ting lids
to keep skunks out of garbage cans.
Habitat Modification
Properly dispose of
garbage or other food sources that will attract skunks.
Skunks are often attracted to rodents living in barns,
crawl spaces, sheds, and garages. Rodent control
programs may be necessary to eliminate this attraction.
Debris such as lumber,
fence posts, and junk cars provide shelter for skunks,
and may encourage them to use an area. Clean up the area
to discourage skunks.
Frightening
Lights and sounds may
provide temporary relief from skunk activity.
Repellents
There are no registered
repellents for skunks. Most mammals, including skunks,
can sometimes be discouraged from entering enclosed
areas with moth balls or moth flakes (naphthalene). This
material needs to be used in sufficient quantities and
replaced often if it is to be effective. Ammonia-soaked
cloths may also repel skunks. Repellents are only a
temporary measure. Permanent solutions require other
methods.
Toxicants
No toxicants are
registered for use in controlling skunks.
Fumigants
Two types of gas
cartridges are registered for fumigating skunk burrows.
Fumigation kills skunks and any other animals present in
the burrows by suffocation or toxic gases. Follow label
directions and take care to avoid fire hazards when used
near structures.
Trapping
Box Traps. Skunks can be
caught in live traps set near the entrance to their den.
When a den is used by more than one animal, set several
traps to reduce capture time. Live traps can be
purchased or built. Figures 4 and 5 illustrate traps
that can be built easily. Consult state wildlife agency
personnel before trapping skunks.
Use canned fish-flavored
cat food to lure skunks into traps. Other food baits
such as peanut butter, sardines, and chicken entrails
are also effective. Before setting live traps, cover
them with canvas to reduce the chances of a trapped
skunk discharging its scent. The canvas creates a dark,
secure environment for the animal. Always approach a
trap slowly and quietly to prevent upsetting a trapped
skunk. Gently remove the trap from the area and release
or kill the trapped skunk.
Captured skunks should be
transported at least 10 miles (16 km) and released in a
habitat far from human dwellings. Attach a length of
heavy string or fishing line to the trap cover and
release the skunk from a distance. Removing and
transporting a livetrapped skunk may appear to be a
precarious business, but if the trap is completely
covered, it is a proven, effective method for relocating
a skunk. If the skunk is to be killed, the US Department
of Agriculture recommends shooting or euthanization with
CO.
Leghold Traps.
Leghold traps should not be used to catch skunks near
houses because of potential problem of scent discharge.
To remove a live skunk caught in a leghold trap, a
veterinarian or wildlife official may first inject it
with a tranquilizer, then remove it from the trap for
disposal or release elsewhere.
Shooting
Skunks caught in leghold
traps may be shot. Shooting the skunk in the middle of
the back to sever the spinal cord and paralyze the hind
quarters may prevent the discharge of scent. Shooting in
the back should be followed immediately by shooting in
the head. Most people who shoot trapped skunks should
expect a scent discharge.
Other Methods
Skunk Removal. The
following steps are suggested for removing skunks
already established under buildings.
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Seal all possible
entrances along the foundation, but leave the main
burrow open.
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Sprinkle a layer of
flour 2 feet (0.6 m) in circumference on the ground
in front of the opening.
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After dark, examine
the flour for tracks which indicate that the skunk
has left to feed. If tracks are not present,
reexamine in an hour.
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After the den is
empty, cover the remaining entrance immediately.
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Reopen the entrance
the next day for 1 hour after dark to allow any
remaining skunks to exit before permanently sealing
the entrance.
A wooden door suspended
from wire can be improvised to allow skunks to leave a
burrow but not to reenter. Burrows sealed from early May
to mid-August may leave young skunks trapped in the den.
If these young are mobile they can usually be
box-trapped easily using the methods previously
described. Where skunks have entered a garage, cellar,
or house, open the doors to allow the skunks to exit on
their own. Do not prod or disturb them. Skunks trapped
in cellar window wells or similar pits may be removed by
nailing cleats at 6-inch (15-cm) intervals to a board.
Lower the board into the well and allow the skunk to
climb out on its own. Skunks are mild-tempered animals
that will not defend themselves unless they are cornered
or harmed. They usually provide a warning before
discharging their scent, stamping their forefeet rapidly
and arching their tails over their backs. Anyone
experiencing such a threat should retreat quietly and
slowly. Loud noises and quick, aggressive actions should
be avoided.
Odor Removal. Many
individuals find the smell of skunk musk nauseating. The
scent is persistent and difficult to remove. Diluted
solutions of vinegar or tomato juice may be used to
eliminate most of the odor from people, pets, or
clothing. Clothing may also be soaked in weak solutions
of household chloride bleach or ammonia. On camping
trips, clothing can be smoked over a cedar or juniper
fire. Neutroleum alpha is a scent-masking solution that
can be applied to the sprayed area to reduce the odor.
It is available through some commercial cleaning
suppliers and the local USDA-APHIS-ADC office. Walls or
structural areas that have been sprayed by skunks can be
washed down with vinegar or tomato juice solutions or
sprayed with neutroleum alpha. Use ventilation fans to
speed up the process of odor dissipation. Where musk has
entered the eyes, severe burning and an excessive tear
flow may occur. Temporary blindness of 10 or 15 minutes
may result. Rinse the eyes with water to speed recovery.
[For more on deodorizing click deodorizing]
Economics of Damage and Control
Skunks should not be
needlessly destroyed. They are highly beneficial to
farmers, gardeners, and landowners because they feed on
large numbers of agricultural and garden pests. They
prey on field mice and rats, both of which may girdle
trees or cause health problems. Occasionally they eat
moles, which cause damage to lawns, or insects such as
white grubs, cutworms, potato beetle grubs, and other
species that damage lawns, crops, or hay.
Skunks occasionally feed
on ground-nesting birds, but their impact is usually
minimal due to the large abundance of alternative foods.
Skunks also feed on the eggs of upland game birds and
waterfowl. In waterfowl production areas, nest
destruction by egg-seeking predators such as skunks can
significantly reduce reproduction. The occasional
problems caused by the presence of skunks are generally
outweighed by their beneficial habits. Some people even
allow skunks to den under abandoned buildings or
woodpiles. Unless skunks become really bothersome, they
should be left alone. An economic evaluation of the
feeding habits of skunks shows that only 5% of the diet
is made up of items that are economically valuable to
people.
The hide of the skunk is
tough, durable, and able to withstand rough use.
Generally there is little market for skunk pelts but
when other furbearer prices are high, skunks are worth
pelting.
Acknowledgments
Much of the information
for this chapter was based on a publication by F. Robert
Henderson.
Figures 1 and 2 from
Schwartz and Schwartz (1981).
Figures 3 through 5 by
Jerry Downs, Graphic Artist, Cooperative Extension
Service, New Mexico State University.
For Additional Information
Burt, W. H., and R. P. Grossenheider. 1976. A field
guide to the mammals, 3d ed. Houghton Mifflin Co.,
Boston. 289 pp.
Deems, E. F., Jr., and D.
Pursley, eds. 1983. North American furbearers: a
contemporary reference. Int. Assoc. Fish Wildl. Agencies
and Maryland Dep. Nat. Resour. 223 pp.
Godin, A. J. 1982. Striped
and hooded skunks. Pages 674-687 in J. A. Chapman and G.
A. Feldhamer, eds. Wild mammals of North America:
biology, management, and economics. The Johns Hopkins
Univ. Press, Baltimore, Maryland.
Howard, W. E., and R. E.
Marsh. 1982. Spotted and hog-nosed skunks. Pages 664-673
in J. A. Chapman and G. A. Feldhamer, eds. Wild mammals
of North America: biology, management, and economics.
The Johns Hopkins Univ. Press, Baltimore, Maryland.
Rosatte, Richard C. 1987.
Striped, spotted, hooded, and hog-nosed skunk. Pages
598613 in M. Novak, J. A. Baker, M. E. Obbard, and B.
Malloch, eds. Wild furbearer management and conservation
in North America. Ministry of Nat. Resour., Ontario,
Canada.
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
01/23/2007
Special
thanks to:
Clemson University
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