range of Eumeces fasciatus, the five-lined skink, 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 penninsula, Missouri, and eastern regions of Kansas, Oklahoma,
and Texas. Isolated populations also occur in northeasten Iowa,
west central Minnesota, and connected portions of southern Minnesota
and Wisconsin (Harding 1997).
Five-lined skinks prefer moist, but not wet, 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, and 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 (Harding 1997). 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 gender of the individual
skink (Fitch 1956). Five-lined skinks seek cover in rotting wood,
rock crevices, vegetation or sawdust piles, or building foundations,
remaining inactive during cold winter months (Harding 1997).
12.70 to 21.60 cm
(5 to 8.5 in)
Adult five-lined skinks, 12.7 to 21.6 cm (5 to 8.5 in) in length,
are characterized by five yellow to cream colored stripes of equal
width running dorsally and laterally 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 maturation
to a brown, gray, or olive hue in adults (Harding 1997). The body
is slender and elongate lacking a distinct neck or narrowing before
the wedge-shaped head. The small limbs are pentadactyl with well
developed toes and claws. Hatchlings, 5 to 6.4 cm in length, 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 (Fitch
1956). Although no sexual difference in body length is apparent,
clear sexual dimorphism of head size and coloration exists among
five-lines skinks (Vitt and Cooper 1986). The development of a widened
head and reddish orange coloration of the snout and jaws intensifies
during the spring breeding season (Harding 1997).
skinks breed once each year.
skinks lay eggs between May and July .
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 (Harding 1997). 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 adjacent areas. Vertical position of
the nest also varies with moisture, with nests located deeper in
a soil cavity at dry sites. Even when nesting sites are not limited,
a significant amount of aggregation occurs (Hecnar 1994). The parchmentlike
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, and varies
due to fluctuations in temperature (Fitch 1956). Females typically
brood their eggs during this time, exhibiting defensive behavior
against smaller predators. Parental care ends a day or two after
hatching when hatchlings leave the nest. Young five-lined skinks,
with a potential life span of up to six years, attain sexual maturity
and begin reproducing within two to three years of hatching (Harding
1997). (Fitch, 1956; Harding, 1997; Hecnar, 1994)
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.
Skinks can live up to 6 years in the wild, although most probably
die as young skinks, before reaching maturity.
male five-lined skinks exhibit complex courtship and aggressive
behavior. Although males tolerate juveniles and females in their
territories, they actively defend these areas against other males.
Vomeronasal analysis of chemical cues and recognition of sex specific
visual stimuli, including tail and body coloration, aid in the identification
of gender (Harding 1997). Evidence suggests that males may rely
more on contact phermones than volatile airborne molecules in the
identification of conspecifics (Cooper and Vitt 1985). Courting
males grasp the necks of receptive females in their jaws after approaching
them from the side. Using the tail to align cloacal openings, males
initiate copulation by inserting one of the two hemipenes into the
female's cloaca. Copulation events typically last four to eight
minutes (Harding 1997).
five-lined skinks demonstrate high levels of parental care which
reduces of egg mortality. Females exhibit several brooding positions
of variant contact levels with the body placed beside, over, through,
or in a coil around the eggs. Brooding position varies according
to soil moisture. Maternal body contact increases at lower moisture
levels potentially reducing transpirational loss of the eggs. In
communal nests, females may alternate foraging and guarding of the
nests, leaving eggs protected at all times (Hecnar 1994). Females
may also urinate in the nests and turn eggs to maintain humidity.
In addition, females transfer heat from basking through body contact.
Any eggs displaced from the nest are retrieved by head or snout
rolling, and rotten eggs are eaten (Harding 1997).
skinks also exhibit antipredation behavior. In evasion of various
predators including snakes, crows, hawks, shrews, moles, opossums,
skunks, raccoons, and domestic cats, skinks may disconnect their
entire tail or a small segment. Skinks run to shelter to escape
their distracted predators as the disconnected tail continues to
twitch. Skinks may also utilize biting as a defensive strategy (Harding
Skinks use their vision and their ability to detect chemicals (pheromones)
to determine the sex of other skinks.
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 (Harding 1997).
crows (Corvus brachyrhynchos)
shrikes (Lanius excubitor)
kestrels (Falco sparverius)
hawks (Accipiter striatus)
foxes (Vulpes vulpes)
opossums (Didelphis virginiana)
skunks (Mephitis mephitis)
cats (Felis silvestris)
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.
Skinks act as a food source for their predators and help to control
insect and other invertebrate populations.
Importance for Humans: Negative
skinks are hosts and carriers of the common chigger, a species that
regularly attacks humans (Fitch 1956).
Importance for Humans: Positive
populations are abundant, five-lined skinks may aid in controlling
insect pests (Harding 1997).
of the five-lined skink is often patchy and colonial, with small
isolated populations in parts of its range. Habitat destruction
in these regions could lead to local extinctions of the species