|Lifespan||Wild: 3 years|
Captivity: 15 years
|Reproduction||Sexual; give live birth|
|Average Height||15.24-22.86 cm (6-9 in) at shoulder|
|Average Weight||1.8-5.5 kg (4-12 lbs)|
|Average Length||55-77 cm (21.65-30.31 in) total|
Great horned owls
|Related Species||Hooded skunk|
The striped skunk (Mephitis mephitis) is a common omnivorous mammal found across North America.
The striped skunk is a stoutly-built, short-limbed animal with a small, conical head and a long, heavily furred tail. Adult males are 10% larger than females, with both sexes measuring between 52 and 77 cm in total body length and usually weighing 1.8–4.5 kg (4.0–9.9 lb), though some may weigh 5.5 kg (12 lb). The feet are plantigrade with bare soles, and are not as broad or flat as those of hog-nosed skunks. The forefeet are armed with five long, curved claws adapted for digging, while those on the hind feet are shorter and straighter.
The color patterns of the fur vary greatly, but generally consist of a black base with a white stripe extending from the head which divides along the shoulders, continuing along the flanks to the rump and tail. Some specimens have a white patch on the chest, while others bear white stripes on the outer surface of the front limbs. Brown or cream-colored mutations occasionally occur.
Like all skunks, the striped skunk possesses two highly developed scent glands, one on each side of the anus, containing about 15 milliliters of musk each, which provides a chemical defense against predation. This oily, yellow-colored musk consists of a mixture of powerfully odorous thiols (sulfur analogues of alcohols, in older sources called "mercaptans"), which can be sprayed at a distance of several meters. The odor of this musk was likened by Ernest Thompson Seton to a mixture of perfume musk, essence of garlic, burning sulfur and sewer gas "magnified a thousand times", though Clinton Hart Merriam claimed that it isn't "one tenth" as offensive as that produced by minks and weasels. It can be sprayed at a distance of several meters. If sprayed on the eyes, this compound can cause a temporary burning sensation.
Reproduction and development
The striped skunk is polygamous, and normally breeds once a year, though yearling females who have failed to mate may enter a second estrous cycle a month after the first. The mating season usually occurs between mid-February to mid-April, though it is delayed at higher latitudes. Prior to copulating, the males' testicles swell during the January–February period, with maximum size being attained in March. Males during this period will cover much ground in their search for females, sometimes covering 4 km (2.5 mi) per night.
When a male locates a female, he will approach her from the rear and lick her genitals, then bite her on the nape before copulating. A single male may have a harem of several females, which he mates with and defends against other males for a period of about 35 days. Once the mating period has finished, the impregnated females confine themselves to their dens, while the males attempt to rebuild their fat reserves.
The gestation period lasts around 59–77 days, with kits being born at about mid-May to early June. Litters generally consist of 2–12 kits, with the average being five or six, though a litter of 18 is known from Pennsylvania. Kits are born blind and sparsely furred, weighing 25–40 grams. The eyes open after around three weeks, and are weaned after 42–56 days. Although their musk is still undeveloped, kits of this age will instinctively assume the defensive stand position when threatened. At this point, the kits may accompany their mother outside the den, becoming independent after 2½ months.
Denning and sheltering behaviors
The striped skunk may dig its own dens, though it will appropriate those abandoned by other animals should the opportunity present itself. These dens are normally used only in late fall, winter, and early spring, while females with unweaned kits make use of them in late spring and summer. In cultivated areas, striped skunks will dig their dens in fencerows, likely because they are less likely to be disturbed by machinery or livestock. In winter it is common for a single den to be occupied by multiple females and a single male. During this period, the striped skunk saves its energy by lowering its body temperature from 38 °C to 32 °C. Although it will forage for short periods in winter, it primarily depends on its fat reserves in cold weather, and can lose as much as 50% of its body weight.
The striped skunk inhabits a wide variety of habitats, particularly mixed woodlands, brushy corners and open fields interspersed with wooded ravines and rocky outcrops. Some populations, particularly in northwestern Illinois, prefer cultivated areas over uncultivated ones.
While primarily an insectivore, the striped skunk is adaptable enough to incorporate other animals and even vegetable matter into its diet. The most frequently consumed insects include grasshoppers, beetles, crickets, caterpillars, other insect larvae and bees. Other invertebrates may include worms, crayfish and other non-insect arthropods. In the winter and spring months, the striped skunk will supplement its diet with vertebrates such as white-footed mice, voles, eggs and the chicks of ground nesting birds. The striped skunk is also known to consume amphibians, reptiles, carrion and fish. Striped skunks inhabiting California's coastal areas will feed on crabs and beached fish. While not adapted for chasing fleet-footed prey, at least one specimen was observed pursuing gray cottontails into their burrows. The skunk will also consume vegetable matter, such as apples, blueberries, black cherries, ground cherries, corn and nightshade when in season.
Striped skunks are known to use their sharp claws to tear apart rotting logs to find grubs, dig in the soil for insects, and pin down prey. Their practice of digging leaves small-but-noticeable pits in the ground, which can provide evidence of their presence in an area.
Because of its formidable defensive capability, the striped skunk has few natural enemies. Mammalian predators typically avoid skunks, unless they are starving. Such predators include cougars, coyotes, bobcats, badgers, and red and gray foxes. Predatory birds, including golden and bald eagles, and great horned owls tend to have greater success in hunting skunks, though they still risk being blinded by their prey's musk.
The striped skunk is one of the major carriers of the rabies virus, second only to raccoons in the US where skunks are 25% of annual cases. Skunks are the primary hosts in the north- and south-central United States as well as in Canada. Cases of rabies in this species are generally epizootic and recurrent. They are also host for the canine parvovirus and may also suffer from leptospirosis.