Agkistrodon contortrix
(broad-banded copperhead)
Geographic Range
Overall, the species inhabits the Florida panhandle
north to Massachusetts and west to Nebraska (Georgia
Wildlife Federation 1999)
The Northern Copperhead (A. c. mokasen) inhabits northern
Georgia and Alabama north to Massachusetts and west to
Illinois.
The Southern Copperhead (A. c. contortrix) inhabits the
Florida panhandle north to Southern Delaware and west to
SE Missouri, SE Oklahoma and E Texas.
The Broad-banded Copperhead (A. c. laticinctus) ranges
from N Oklahoma to south-central Texas.
The Osage Copperhead (A. c. phaeogaster) lives in eastern
Missouri to eastern Kansas and south to northeastern
Oklahoma.
The Trans-pecos Copperhead (A. c. pictigaster) lives in
west Texas.
(Conant and Collins 1998)
Biogeographic Regions: nearctic (native ).
Habitat
Copperheads prefer terrestrial to semi-aquatic
habitats, which include rocky-forested hillsides and
various wetlands (Tyning 1990). They have also been known
to occupy abandoned and rotting slab or sawdust piles
(Conant 1998).
Terrestrial Biomes: forest .
Physical Description
Average length of adult copperheads is 30 inches. They
have an unmarked copper-colored head, reddish-brown,
coppery bodies with chestnut brown crossbands that
constrict towards the midline. Copperheads are
thick-bodied and have keeled scales.
There is a temperature sensitive pit organ on each side of
the head between the eye and the nostril. There is a
single row of scales beneath the tail (Schmidt 1941,
Tyning 1990)
Tails have no rattle (Ernst 1989)
Young Copperheads are 7-10 inches long and grayer in color
than adults. They have a sulfur yellow tipped tail, which
fades with age and is lost by age 3 or 4
Copperheads are sexually dimorphic in size.
Males have longer tails then females and females grow to
greater lengths (Tyning 1990)
The head of the Northern Copperhead is a red, copper color
with the rest of its body being pinkish to gray-brown with
a dark chestnut colored hourglass shaped pattern. The
hourglass pattern is narrow on the top of its back and
wider on its sides. It has elliptical pupils and facial
pits between its eyes and nostrils(Ohio DNR 1999). The
underside, belly area, of the northern subspecies is dark
(Schmidt 1942).
Southern Copperhead is similar to the northern copperhead
but the coloration is paler and the crossbands fail to
meet at the midline. Also the belly of the southern
subspecies is light in color(Schmidt 1941).
Broad-banded Copperhead have bright coloration with a
sharp contrast between the pattern and the ground color.
The crossbands are very broad at the midline and always
meet. The belly is dark (Schmidt 1941).
Osage Copperhead is similar to those of the northern
subspecies but the crossbands are often edged in
white(Conant and Collins 1998).
The belly of the Trans-pecos Copperhead is strongly
patterned. Also there is a pale area located at the base
of each broad crossband (Conant and Collins 1998).
Some key physical features: ectothermic ; bilateral
symmetry .
Reproduction
The life span of the copperhead is 18 years. Both
sexes reach sexual maturity at 4 years when they are about
two feet in length. However, Ernst (1989) notes that the
age and size of maturity in the male copperhead is
unknown. The breeding season is from February to May and
from August to October. Females who breed in autumn can
store the sperm until after she emerges from the
overwintering site (Tyning 1990). The length of time that
the sperm can be stored appears to differ depending on
where it is being stored. If the sperm is stored in the
cloaca, it only lasts a relatively short time, whereas if
it is stored in the upper end of the oviducts in vascular
tissues specialized as seminal receptacles it seems to
last much longer (Ernst 1989). Copperheads have a
gestation period of 3-9 months. They are a live-bearing
snake, typically producing 2-10 young, where larger
females produce larger broods. After birth, the female
provides no direct care for the young (Tyning 1990).
Females are ovoviviparous (eggs develop in the body of the
female and hatch within or immediately after being
expelled. They produce large, yolk-filled eggs and store
the eggs in the reproductive tract for development. The
embryo, during this time, receives no nourishment from the
female, only from the yolk. The young are expelled in a
membranous sac weighing less than an ounce and 7-10 inches
in length (Ohio DNR 1999).
Key reproductive features: gonochoric/gonochoristic/dioecious
(sexes separate).
Behavior
MATING:
Mating begins in the spring after the snakes emerge from
winter dens (there are some reports of autumn mating). At
this time males begin to seek out sexually active females
using their tongue to detect pheromones in the air. Once
he has located a female, the male will begin moving his
head or rubbing his chin on the ground. Eventually, after
a lot of tail movements, slow to rapid back to forth
waving from the female, the male aligns his body with
hers. This courtship may last for an hour or more if the
female does not respond. After being sufficiently
stimulated, the female lifts and arches her tail and
lowers the scale that covers her cloaca. Then the male
arches his body and tail, everting one of his two sex
organs and mates with the female. Mating time varies, the
range can be as much as 3.5 to 8.5 hours. The long mating
time correlates with the fact that females usually only
mate with one male per year. This is because during the
mating period males produce a pheromone that makes the
female unattractive to other males, who pay little or no
attention to mating or just mated females. Females also
have little interest in mating after a long successful
first mating (Tyning 1990).
SOCIAL:
This is a social snake, which may overwinter in a communal
den with other copperheads or other species of snakes
including timber rattlesnakes and black rat snakes. They
tend to return to the same den year after year. Females
with young are gregarious whereas barren females and males
are solitary (Ohio DNR 1999). Copperheads are found close
to one another near denning, sunning, courting, mating,
eating and drinking sites. The are believed to migrate
late in the spring to reach summer feeding territories and
reverse this migration in early autumn. Males are
aggressive during the spring and autumn mating seasons.
They will try to overpower each other and even pin the
others body to the ground. This behavior is exhibited most
often in front of females but is not always the case.
These interactions can include elevating their bodies,
swaying side to side, hooking each others necks,
eventually intertwining their entire body length (Tyning
1990). Copperheads have been reported to climb into low
bushes or trees after prey or to bask in the sun. They
have also been seen voluntarily entering water and
swimming on numerous occasions (Ernst 1989).
Key behaviors: motile .
Food Habits
The Copperhead is primarily a carnivore, as an adult
eating mostly mice but also small birds, lizards, small
snakes, amphibians and insects-especially cicadas (Conant
and Collins 1998). The snakes are capable of swallowing
prey that is several times larger than their own diameter.
This is possible because they have a very flexible jaw and
it has digestive juices that allow it to digest both bones
and fur. Copperheads have fangs that inject its prey with
a hemolytic venom (causes the breakdown of red blood
cells) which subdues its prey, making it easy for the
snake to swallow it. The copperhead seeks out its prey
using its heat sensitive pits to detect objects that are
warmer then its environment. This also enables them to
find nocturnal mammalian prey (Ohio DNR 1999). Adult
copperheads are primarily ambushers. When attacking large
prey, the copperhead bites then releases immediately to
allow the venom to take its effect then later tracks its
prey. Whereas the smaller prey is held in its mouth until
it dies (Ernst 1989). When the copperhead eats depends on
the time of the year. They are most active April through
late October, diurnal in the spring and fall, and
nocturnal during the summer months (Ohio DNR 1999). When
carrying young, some females will not eat at all because
the embryos occupy so much of the body cavity. It has been
found that some copperheads consume only eight meals in a
single growing season. The only possible explanations for
this could be due to a slow metabolism and/or difficulty
finding prey ( Tyning 1990).
Young copperheads eat mostly insects, especially
caterpillars, and use their yellow tipped tails to
function as a worm-like lure to attract prey (Georgia
Wildlife Federation 1999).
Conservation Status
No special status federally, however it is listed in
the state of Massachusetts as endangered (Umass 1999).
Other Comments
Venom and Bites:
The copperhead has solenogiyphous fangs that tend to be
1.1-7.2 mm in length. The length of the snake relates to
the length of the fangs; the longer the snake, the longer
the fangs. Even newborn copperheads have fully functional
fangs that are capable of injecting venom. These newborns
have venom that is just as toxic as adults do. The fangs
are replaced periodically with each snake having a series
of five to seven replacement fangs in the gums behind and
above the current functional fang.
The venom, which is highly hemolytic, causes massive
hemorrhaging to the copperhead's prey. As for humans,
recorded symptoms include pain, swelling, weakness,
giddiness, breathing difficulty, hemorrhage, either an
increased or decreased pulse, nausea, vomiting, gangrene,
ecchymosis, unconsciousness, stupor, fever, sweating,
headache and intestinal discomfort. The copperhead is the
cause of many snakebites yearly but they are rarely fatal.
Bites occur by accidentally stepping on or touching the
snake, which tends to be well camouflaged with its
surroundings. When touched, the copperhead quickly strikes
or remains quiet and tries to crawl away. Sometimes when
touched, they emit a musk that smells like cucumbers
(Ernst 1989).
(source:
http://animaldiversity.ummz.umich.edu/site/accounts/information/Agkistrodon_contortrix.html) |