Geographic Range
American hog-nosed skunks (
Conepatus leuconotus
) are a Neartic species found in Central America, Mexico, and the southern United
States. They can range as far south as Guatemala, El Salvador, Honduras and the northern
parts of Nicaragua. American hog-nosed skunks are prevalent throughout all of Mexico,
excluding the Yucatan and Baja Peninsulas. In the United States, they range throughout
southwestern Texas, continuing into the southern half of New Mexico and central Arizona.
Their range continues into the southeastern corner of Colorado and includes a small,
isolated population to the north of Houston, Texas.
Habitat
American hog-nosed skunks inhabit a wide range of habitats. Some of these include
foothills, grasslands, mountains, and bushy areas throughout their range. American-hog
nosed skunks are most common in very rocky and mountainous terrain, where crevices
and caves serve as dens. In mountainous areas, they can be found at altitudes up to
3048 m in Mexico, and 2743 m in Arizona. Additional habitats include foothills, grasslands,
temperate forests and, occasionally, farmland. Here, dens can be in old burrows, shrubs,
rocky spaces, hollowed trees and underneath buildings in suburban areas.
- Habitat Regions
- temperate
- terrestrial
- Terrestrial Biomes
- savanna or grassland
- forest
- mountains
- Other Habitat Features
- suburban
- agricultural
- caves
Physical Description
Like most skunk species, American hog-nosed skunks have black-and-white pelage. The difference between the fur of American hog-nosed skunks and other species is the single white stripe that runs from the top of the head, starting in a wedge shape, to the tip of the tail. Some individuals from the northwestern part of their range have more white on their dorsa. The dorsal sides of their tails is primarily white, while their ventral sides can be either black or white, with sparse black hairs throughout the white fur. Their fur is short and very coarse with a thinner undercoat. Both sexes have the same coloring. Kits are born with black and white markings on their skin along with fine hair covering their bodies.
The defining feature that sets American hog-nosed skunks apart from other skunk species
is their large naked snout that resembles that of hogs (
Sus scrofa
) or honey badgers (
Mellivora capensis
). Their eyes and noses are both very small in comparison to their snouts and bodies.
Their legs are stocky, and they possess five-toed plantigrade feet. They have claws
on each toe, but those on their front feet are larger for rooting through the ground.
Males are slightly larger than females and, on average, are about 577 mm in total
length while females averages around 542 mm long. Other measurements includes an average
tail-length range of 122 to 410 mm, hind foot lengths of 22 to 90 mm, ear lengths
for 8 to 36 mm. Weights for males range from 1.1 to 4.5 kg and females are almost
always 10% lighter. Their dental formula is 3121/3132, for a total of 32 teeth.
- Other Physical Features
- endothermic
- bilateral symmetry
- Sexual Dimorphism
- sexes alike
- male larger
Reproduction
American hog-nosed skunks are polygynous; males mate with multiple females throughout
the breeding season. There is no photographic evidence of copulation during the months
of February or March, leading researchers to believe it takes place away from their
dens. During these observations, males and females were seen to be following each
other, showing common signs of courtship, mate guarding, and assurance of paternity.
- Mating System
- polygynous
The typical breeding season of hog-nosed skunks seems to begin in late February to
early March, with females becoming pregnant mostly in late March. Typically there
is only one breeding period per year, but there may be a secondary peak in May or
June. This second peak could include males attempting to mate again with females who
did not have a pregnancy or lost a pregnancy. Gestation periods average 60 days (range
42 to 70 days) with young born in April or May. Litter size is usually 2 to 4 (range
1 to 5). These skunks have 3 pairs of mammae that contribute to the small litter size,
with 2 pairs of pectoral and 1 pair of inguinal mammae. Kits are born blind, with
a thin layer of fur over black-and-white-colored skin. They also have the ability
to use a small amount of musk. Kits can move around in their nests with their eyes
still closed. Their average weight is about 450 g, about a month after birth. Kits
become independent by late August and sexually mature by 10 or 11 months.
- Key Reproductive Features
- iteroparous
- seasonal breeding
- gonochoric/gonochoristic/dioecious (sexes separate)
- sexual
- fertilization
- viviparous
Male American hog-nosed skunks have no parental investment beyond the act of mating.
Females provide necessary nutrition and protection during the short 4-month period
until kits reach independence.
- Parental Investment
- precocial
- female parental care
-
pre-fertilization
-
protecting
- male
-
protecting
-
pre-hatching/birth
-
provisioning
- female
-
protecting
- female
-
provisioning
-
pre-weaning/fledging
-
provisioning
- female
-
protecting
- female
-
provisioning
-
pre-independence
-
provisioning
- female
-
protecting
- female
-
provisioning
Lifespan/Longevity
American hog-nosed skunks are expected to have a lifespan on average of about 3 to
4 years in the wild, while in captivity they can live as much as 14 years. A large
factor in the lives of these skunks are humans and, more specifically, mortality due
to vehicles and roadways.
Behavior
American hog-nosed skunks are mainly solitary animals. Part of their geographic range in Central America is known for its hot temperatures and desert areas. American hog-nosed skunks do not emerge during the daytime heat in this area and instead come out at night as well as during the hours of dusk and dawn. During winter, hog-nosed skunks emerge during the day. Bailey (1931) captured skunks that weighed more in the winter season, suggesting that these skunks are torpid for short time frames in winter months. Davis and Schmidly (1994) recount the report of a trapper in central Texas who found two individuals occupying a winter den.
When American hog-nosed skunks are in danger, their first line of defense is to flee with their tail curled over their backs to the nearest safe space, such as a den, bush or tree hollow. If this technique does not get them out of danger, hog-nosed skunks will turn and face their threat with low growls and stamp their feet on the ground. If a predator approaches, skunks will stand on their hind legs, take a few steps forward, and stomp down hard on the ground and emit a loud hiss. While still facing the threat, American hog-nosed skunks will then draw their legs back and lay close to the ground while using their large claws to scrape up dirt. As a last resort, these skunks will turn and raise their tails in order to spray out a noxious liquid that will deter most predators from pursuing any further. If in an area with little ground cover, American hog-nosed skunks will climb trees if necessary. This behavior has only been observed when being pursued by humans in this type of terrain.
American hog-nosed skunks are opportunistic insectivores that forage in the soil.
Their foraging habits have been described as digging through the top few centimeters
of topsoil in a circle approximately 12 m in diameter.
- Key Behaviors
- terricolous
- diurnal
- nocturnal
- crepuscular
- motile
- aestivation
- daily torpor
- solitary
Home Range
Brashear (2015) used 15 male and 14 female hog-nosed skunks to monitor their spatial usage and home range. Using a 95% fixed-kernel estimate for both sexes, Brashear discovered an average male home range encompassing 1.94 km^2, while females averaged 0.638 km^2. Defended territories have not been reported.
Skunk densities have been reported to be 0.6 individuals per km^2 in the wet season.
In the dry season, the densities increase to 1.3 skunks per km^2.
Communication and Perception
While American hog-nosed skunks are nocturnal, they rely heavily on their sense of smell not only for finding food, but also for protection. While their noses are used for smelling, American hog-nosed skunks use their noses to dig and root in the ground to forage. Large front claws are used in digging to search for anything edible. Like other skunk species, they are known to have poor vision, only being able to see what is directly in front of them. When in danger, these skunks will raise their tail in warning and flee to a safe space such as a den, shrubs, or fallen trees.
For all species of skunks, their chemical defense is widely understood to be a very
smelly secretion that keeps most animals away. This liquid is secreted from two scent
glands that are found at the base of their tails, on either side of their rectums.
These glands are covered by a smooth muscle that contracts to force out either a stream
or a mist. This mechanism is extremely accurate and can be aimed at specific targets,
such as potential predators.
Food Habits
American hog-nosed skunks are omnivores, consuming animals, fruit, and plants. The
primary staple in their diet consists of different insects. Schmidly and Bradley (2016)
reported 83 skunk stomachs that were examined during different seasons to see if their
diets changed based on differing weather conditions. In the winter, 76% of their diet
consisted of insects, 12% arachnids, 9% small mammals, and 3% vegetation. Spring diets
consisted of 82% insects, 12% arachnids and 6% reptiles. Summer diets included 50%
insects, 31% vegetation, 9% arachnids, 5% snails, 3% small mammals and 2% reptiles.
Autumn diets contain 58% insects, 38% vegetation, 6% reptiles, and 4% arachnids.
American hog-nosed skunks tend to stay away from desert areas - most likely due to
the heat - and are primarily nocturnal. Night is when these skunks actively root for
food, except during the winter. Using their noses, these skunks use their sense of
smell to find their meals. They either use their large snouts to root in the ground,
or dig into the ground with their large front claws, even turning up rocks to find
grubs underneath. While foraging, these skunks dig through the top few centimeters
of the topsoil in a circle 12 meters in diameter.
- Primary Diet
-
carnivore
- eats terrestrial vertebrates
- insectivore
- eats non-insect arthropods
- molluscivore
- vermivore
- herbivore
- omnivore
- Animal Foods
- mammals
- reptiles
- insects
- terrestrial non-insect arthropods
- mollusks
- terrestrial worms
- Plant Foods
- fruit
- flowers
Predation
American hog-nosed skunks have multiple anti-predator adaptations that include their
fur color and their musky chemical defense. The black and white fur of these skunks
helps them stay camouflaged during the night, when they are mainly active. This patterning
also wards off predators from giving chase because it can be confusing when they are
moving. The distinct patterns of all skunks warn predators of the musk that they can
spray when threatened. Hog-nosed skunks are frequently preyed upon by larger mammals,
such as coyotes (
Canis latrans
), red foxes (
Vulpes vulpes
), gray foxes (
Urocyon cinereoargenteus
), cougars (
Puma concolor
), bobcats (
Lynx rufus
), American badgers (
Taxidea taxus
). Some predatorial birds include great horned owls (
Bubo virginianus
), golden eagles (
Aquila chrysaetos
), and bald eagles (
Haliaeetus leucocephalus
). Humans (
Homo sapiens
) are also a large contributor to the mortality of these skunks, because many humans
trap and kill other species of skunks for being pests. Humans also unknowingly trap
hog-nosed skunks due to their close coloring similarities to other species. They are
also frequently roadkill.
- Anti-predator Adaptations
- aposematic
- cryptic
Ecosystem Roles
American hog-nosed skunks have overlapping territories with 4 species of skunks: striped skunks ( Mephitis mephitis ), hooded skunks ( Mephitis macroura ), eastern spotted skunks ( Spilogale putorius ), and western spotted skunks ( Mephitis gracilis ). Hog-nosed skunks tend to keep to themselves and avoid other species in their area because they are much less commensal with humans than striped skunks. Even though these species tend to avoid each other, they are still competitors for food. Additional competitors include nine-banded armadillos ( Daspus novemcintus ), Virginia opossums ( Didelphis virginianus ), and wild boars ( Sus scrofa ). The only known mutualistic relationships that hog-nosed skunks have can encompass many species that dig or create dens big enough for the skunks to take over. Another relationship comes from the digging and rooting habits that can both aerate soils and create microhabitats for smaller animals.
American hog-nosed skunks host fleas (
Pulex
) and ticks (
Ixodes texanus
). They are also hosts to other parasites that include intestinal and sinus roundworms,
cestodes, and subcutaneous nematodes. Studies in Texas show lungworms (
Filaroides milksi
), other nematodes such as
Filaria taxidaea
,
Gongylonema
,
Macracanthorhynchus ingens
,
Oncicola canis
,
Pachysentis canicola
,
Physaloptera maxillaris
,
Physaloptera rara
, and a specific cestode
Mathevotaenia mephitis
, in hog-nosed skunks.
- Ecosystem Impact
- creates habitat
- soil aeration
- Fleas ( Pulex )
- Ticks ( Ixodes texanus )
- Nematodes ( Filaroides milksi )
- Nematodes ( Filaria taxidaea )
- Nematodes ( Gongylonema )
- Nematodes ( Macracanthorhynchus ingens )
- Cestodes ( Mathevotaenia mephitis )
- Nematodes ( Oncicola canis )
- Nematodes ( Pachysentis canicola )
- Nematodes ( Physaloptera maxillaris )
- Nematodes ( Physaloptera rara )
Economic Importance for Humans: Positive
American hog-nosed skunks are killed for their pelts, but not throughout their range;
these pelts are very coarse and typically of little value.
- Positive Impacts
- body parts are source of valuable material
Economic Importance for Humans: Negative
Hog-nosed skunks can become a nuisance to humans when skunks steal eggs or otherwise disrupt poultry on farms. They can also cause damage in residential areas by digging up lawns, gardens, and golf courses in their attempts to root for food. Hog-nosed skunks are a carrier of rabies that can be transmitted to humans.
A rabies study in San Luis Potosi, Mexico (1991-1997) found that skunks were carriers;
American hog-nosed skunks represented 3 of the 10 positive skunk cases. Although there
are no reports of them transmitting rabies to humans, it is likely because these skunks
avoid human habitation.
- Negative Impacts
-
injures humans
- carries human disease
- crop pest
- causes or carries domestic animal disease
Conservation Status
While stated on IUCN Red List that populations seem to be decreasing, the American
hog-nosed skunks are listed as a species of "Least Concern." CITES, the US Federal
List and the State of Michigan List cite this species as having no special status.
The primary threat to American hog-nosed skunks is human use of roadways splitting
their territories. These skunks are often only seen by humans as roadkill and are
not differentiated from other species of skunks that also fall victim to traffic accidents.
Other threats to hog-nosed skunks include habitat degradation and fragmentation from
humans. Animal control measures such as pesticides also have both indirect and direct
effects on American hog-nosed skunks and their prey. More natural threats to these
skunks include interspecific competition, parasites and diseases.
As a species of least concern, American hog-nosed skunks have very little conservation
efforts in place. More research about populations across their geographic range needs
to be conducted. Efforts already put in place by the USDA Forest Service include roadkill
surveys, range-wide inventory, habitat assessments, and threat refinements. Only after
more data are collected can a better effort to conserve hog-nosed skunks be put in
place, and conservation management can be set in motion. Internationally, there have
been suggestions to list the entire genus (
Conepatus
) in CITES Appendix II, so that rarer members of the genus are afforded protection
in trade.
Other Comments
The secretions of American hog-nosed skunks can be sprayed either standing still or
when on the run from a threat. The chemical composition of the liquid is mainly composed
of (E)-2-butene-1-thiol and (E-S)-2-butenyl thioacetate along with some minor components
of phenyl methanethiol, 2-methyl quinoline, 2-quinoline-methanethiol and bis[(E)-2-butenyl]disulfide.
Additional Links
Contributors
Kayla Nelson Anderson (author), Radford University, Lauren Burroughs (editor), Radford University, Layne DiBuono (editor), Radford University, Lindsey Lee (editor), Radford University, Karen Powers (editor), Radford University, Galen Burrell (editor), Special Projects.
- Nearctic
-
living in the Nearctic biogeographic province, the northern part of the New World. This includes Greenland, the Canadian Arctic islands, and all of the North American as far south as the highlands of central Mexico.
- native range
-
the area in which the animal is naturally found, the region in which it is endemic.
- temperate
-
that region of the Earth between 23.5 degrees North and 60 degrees North (between the Tropic of Cancer and the Arctic Circle) and between 23.5 degrees South and 60 degrees South (between the Tropic of Capricorn and the Antarctic Circle).
- terrestrial
-
Living on the ground.
- tropical savanna and grassland
-
A terrestrial biome. Savannas are grasslands with scattered individual trees that do not form a closed canopy. Extensive savannas are found in parts of subtropical and tropical Africa and South America, and in Australia.
- savanna
-
A grassland with scattered trees or scattered clumps of trees, a type of community intermediate between grassland and forest. See also Tropical savanna and grassland biome.
- temperate grassland
-
A terrestrial biome found in temperate latitudes (>23.5° N or S latitude). Vegetation is made up mostly of grasses, the height and species diversity of which depend largely on the amount of moisture available. Fire and grazing are important in the long-term maintenance of grasslands.
- forest
-
forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.
- mountains
-
This terrestrial biome includes summits of high mountains, either without vegetation or covered by low, tundra-like vegetation.
- suburban
-
living in residential areas on the outskirts of large cities or towns.
- agricultural
-
living in landscapes dominated by human agriculture.
- polygynous
-
having more than one female as a mate at one time
- iteroparous
-
offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).
- seasonal breeding
-
breeding is confined to a particular season
- sexual
-
reproduction that includes combining the genetic contribution of two individuals, a male and a female
- fertilization
-
union of egg and spermatozoan
- viviparous
-
reproduction in which fertilization and development take place within the female body and the developing embryo derives nourishment from the female.
- young precocial
-
young are relatively well-developed when born
- female parental care
-
parental care is carried out by females
- diurnal
-
- active during the day, 2. lasting for one day.
- nocturnal
-
active during the night
- crepuscular
-
active at dawn and dusk
- motile
-
having the capacity to move from one place to another.
- solitary
-
lives alone
- visual
-
uses sight to communicate
- tactile
-
uses touch to communicate
- chemical
-
uses smells or other chemicals to communicate
- visual
-
uses sight to communicate
- tactile
-
uses touch to communicate
- chemical
-
uses smells or other chemicals to communicate
- aposematic
-
having coloration that serves a protective function for the animal, usually used to refer to animals with colors that warn predators of their toxicity. For example: animals with bright red or yellow coloration are often toxic or distasteful.
- cryptic
-
having markings, coloration, shapes, or other features that cause an animal to be camouflaged in its natural environment; being difficult to see or otherwise detect.
- soil aeration
-
digs and breaks up soil so air and water can get in
- causes or carries domestic animal disease
-
either directly causes, or indirectly transmits, a disease to a domestic animal
- carnivore
-
an animal that mainly eats meat
- insectivore
-
An animal that eats mainly insects or spiders.
- molluscivore
-
eats mollusks, members of Phylum Mollusca
- herbivore
-
An animal that eats mainly plants or parts of plants.
- folivore
-
an animal that mainly eats leaves.
- frugivore
-
an animal that mainly eats fruit
- omnivore
-
an animal that mainly eats all kinds of things, including plants and animals
- endothermic
-
animals that use metabolically generated heat to regulate body temperature independently of ambient temperature. Endothermy is a synapomorphy of the Mammalia, although it may have arisen in a (now extinct) synapsid ancestor; the fossil record does not distinguish these possibilities. Convergent in birds.
- bilateral symmetry
-
having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.
References
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Arbuckle, K. 2015. On the Macroevolution of Antipredator Defence (Masters Thesis) . Liverpool, England: University of Liverpool.
Bailey, V. 1931. North American Fauna No. 53 Mammals of New Mexico . Washington D.C.: United States Department of Agriculture Bureau of Biological Survey.
Brashear, W., A. Ferguson, N. Negovetich, R. Dowler. 2015. Spatial organization and home range patterns of the American hog-nosed skunk (Conepatus leuconotus). The American Midland Naturalist , 174/2: 310-320.
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Ellsworth, Z. 2016. Evaluating the Reproductive Habits and the Breeding Season of the Hog-nosed Skunk (Conepatus leuconotus) (Masters Thesis) . San Angelo, Texas: Angelo State University.
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Gómez-Ortiz, Y., O. Monroy-Vilchis, G. Mendoza-Martinez. 2015. Feeding interactions in an assemblage of terrestrial carnivores in central Mexico. Zoological Studies , 54: 16. Accessed February 05, 2019 at https://doi.org/10.1186/s40555-014-0102-7 .
Helgen, K. 2016. "Conepatus leuconotus" (On-line). The IUCN Red List of Threatened Species 2016: e.T41632A45210809. Accessed January 29, 2019 at http://dx.doi.org/10.2305/IUCN.UK.2016-1.RLTS.T41632A45210809.en .
Leopold, A. 1959. Wildlife of Mexico: The Game Birds and Mammals . Los Angeles, California: University of California Press.
Rohde, R., E. Oertli, P. Wilson, P. Hunt, T. Sidwa. 2009. Epidemiology of rabies in skunks in Texas. Journal of the American Veterinary Medical Association , 234/5: 616-620.
Russell, R., W. Davis. 1954. Mammals of the Mexican state of Morelos. Journal of Mammalogy , 35/1: 63-80.
Schmidly, D., R. Bradley. 2016. The Mammals of Texas . Austin, Texas: University of Texas Press.
USDA Forest Service. American hog-nosed skunk (Conepatus leuconotus): A technical conservation assessment. None. Washington, D.C.: USDA Forest Service. 2006. Accessed February 05, 2019 at https://www.fs.usda.gov/Internet/FSE_DOCUMENTS/stelprdb5181906.pdf .