Adult Five-lined Skinks are from 12.7 to 21.6 cm in length. They are characterized by five yellow to cream colored stripes of equal width running from the snout to tail. These stripes, separated by darker lines, may lighten with age, eventually disappearing in older males. The typical black background color of juveniles and young adult females also fades with age to a brown, gray, or olive hue in adults. The body is slender and long and lacks a distinct neck. The head is wedge-shaped. The small limbs have five toes each with well-developed claws. Hatchlings are from 5 to 6.4 cm in length. They possess bright blue tails and distinct white or yellow stripes on a black background. Tail color dulls with age, and is more commonly retained in females than males, which display gray tails as adults. Males and females are different in head size and overall coloration. Males develop a widened head and reddish-orange coloration of the snout and jaws during the spring breeding season.
The range of Five-lined Skinks extends south from the lower peninsula of Michigan, southern Ontario, and eastern New York to northern Florida, and west to Wisconsin, part of Michigan's upper peninsula, Missouri, and eastern regions of Kansas, Oklahoma, and Texas. Isolated populations also occur in northeastern Iowa, and west central Minnesota.
Five-lined Skinks prefer moist wooded or partially wooded areas with significant cover and abundant basking sites. These sites may include wood or brush piles, stumps, logs, rocky outcrops, loose bark, or abandoned buildings. Most Five-lined Skinks inhabit disturbed environments, such as forest edges, cleared areas, or burned regions, commonly called ecotone areas. Five-lined Skink populations may also occur among driftwood piles on the sandy beaches of the Great Lakes. Home range size is affected by available habitat type as well as changes in seasonal food distribution, shelter, and other requirements. Home range may also vary in size and shape in accordance with the age and sex of the skink. Five-lined Skinks seek cover in rotting wood, rock crevices, vegetation, or building foundations, remaining inactive during the cold winter months.
The egg incubation length varies with temperature, so that colder temperatures lead to longer times to hatching.
Fertilization in five-lined skinks is internal, with eggs laid by the female between the middle of May and July, at least one month after mating. Females lay fifteen to eighteen eggs in a small cavity cleared beneath a rotting log, stump, board, loose bark, a rock, or an abandoned rodent burrow. Females prefer secluded nest sites in large, moderately decayed logs. Soil moisture is also an important factor in nest selection. Females often place nests in regions where soil moisture is higher than in nearby areas. Even when nesting sites are abundant, female skinks tend ot nest near each other. The parchment-like eggs of Five-lined Skinks, similar to many other reptiles, are thin and easily punctured. Freshly laid eggs range from spherical to oval in shape averaging 1.3 cm in length. Absorption of water from the soil leads to increased egg size. Egg coloration also changes over time, from white to mottled tan, after contact with the nest burrow. The incubation period ranges from 24 to 55 days, depending on the temperature. Young Five-lined Skinks become mature and begin reproducing within two to three years of hatching.
Females typically brood their eggs during incubation, defending them against small predators. Females place their bodies around or over their eggs, depending on soil moisture. Females try to cover the eggs more when the soil is dry, to reduce water loss from the eggs. They will also urinate on the eggs to maintain their moisture. Females keep their eggs warm by basking in the sun, then returning to the nest to warm the eggs with their body heat. Females form communal nests where they may share in the care of eggs, alternating between foraging and guarding eggs so that eggs remain protected all of the time. Any eggs displaced from the nest are retrieved by head or snout rolling, and rotten eggs are eaten. Parental care ends a day or two after hatching, when hatchlings leave the nest.
Five-lined Skinks can live up to 6 years in the wild, although most probably die as young skinks, before reaching maturity.
Five-lined Skinks are mostly active during the day, taking refuge at night. They find protected areas, such as under logs or other debris, to stay through the winter in a state of suspended animation. Males actively defend small territories against other males. Five-lined Skinks are mainly solitary but females may cooperate to guard their eggs.
Five-lined Skinks use their vision and their ability to detect chemicals (pheromones) to determine the sex of other skinks.
Five-lined skinks are generally insectivorous, feeding on spiders, millipedes, crickets, termites, grasshoppers, caterpillars, beetles, and beetle larvae. They may also consume snails, as well as small vertebrates including frogs, smaller lizards, and newborn mice.
Five-lined skinks are preyed on by large birds, such as American crows, northern shrikes, American kestrels, or sharp-shinned hawks. They are also preyed on by foxes, raccoons, opossums, skunks, shrews, moles, domestic cats, and snakes. Five-lined skinks are quick to escape and take refuge in crevices. If confronted with a predator, skinks may disconnect their entire tail or a small segment. The tail is often brightly colored and twitches, this distracts the predator long enough for the skink to run away. They re-grow their tails over time. Skinks also bite at their attackers.
Five-lined Skinks act as a food source for their predators and help to control insect and other invertebrate populations.
Five-lined Skinks are hosts and carriers of the common chigger, a species that also attacks humans.
Where populations are abundant, Five-lined Skinks may aid in controlling insect pests.
Five-lined skinks occur in small, isolated popuations in parts of their range. These populations are especially vulnerable to habitat destruction or natural catastrophes and may become extinct in those areas.
Elizabeth Vanwormer (author), Michigan State University, James Harding (editor), Michigan State University.
Cooper, W., L. Vitt.. 1985. Responses of skinks, E. fasciatus and E. laticeps to airborne conspecific odors: further appraisal. Journal of Herpetology, 19: 481-486.
Fitch, H. 1956. Life history and ecology of the five-lined skink, Eumeces fasciatus. Pp. 1-156 in E Hall, A Leonard, R Wilson, eds. University of Kansas Museum of Natural History Publications volume 8. Topeka, Kansas: University of Kansas.
Harding, J. 1997. Amphibians and Reptiles of the Great Lakes Region. Ann Arbor, Michigan: University of Michigan Press.
Hecnar, S. 1994. Nest distribution, site selection, and brooding in the five-lined skink (Eumeces Fasciatus). Canadian Journal of Zoology, 72: 1510-1516.
Vitt, L., W. Cooper.. 1986. Skink reproduction and sexual dimorphism: Eumeces fasciatus in S.E. United States with notes on E. inexpectus. Journal of Herpetology, 20: 65-76.