Agkistrodon contortrix
Encyclopedia
Agkistrodon contortrix is a species of venomous snake
found in North America
, a member of the Crotalinae (pit viper)
subfamily. The more common name for the species is "copperhead". The behavior of 'Agkistrodon contortrix' may lead to accidental encounters with humans. Five subspecies
are currently recognized, including the nominate subspecies described here.
(Ditmars, 1931). Brimley (1944) mentions a specimen of A. c. mokasen from Chapel Hill, North Carolina
, that was "four feet, six inches" (137.2 cm), but this may have been an approximation. The maximum length for A. c. contortrix is 132.1 cm (52 in) (Conant, 1958).
The body is relatively stout and the head is broad and distinct from the neck. Because the snout slopes down and back, it appears less blunt than that of the cottonmouth, A. piscivorus
. Consequently, the top of the head extends further forward than the mouth.
The scalation includes 21-25 (usually 23) rows of dorsal scales
at midbody, 138-157 ventral scales
in both sexes and 38-62/37-57 subcaudal scales
in males/females. The subcaudals are usually single, but the percentage thereof decreases clinally from the northeast, where about 80% are undivided, to the southwest of the geographic range where as little as 50% may be undivided. On the head there are usually 9 large symmetrical plates, 6-10 (usually 8) supralabial scales
and 8-13 (usually 10) sublabial scales
.
The color pattern consists of a pale tan to pinkish tan ground color that becomes darker towards the midline, overlaid with a series of 10-18 (13.4) crossbands. Characteristically, both the ground color and crossband pattern are pale in A. c. contortrix. These crossbands are light tan to pinkish tan to pale brown in the center, but darker towards the edges. They are about 2 scales wide or less at the midline of the back, but expand to a width of 6-10 scales on the sides of the body. They do not extend down to the ventral scales. Often, the crossbands are divided at the midline and alternate on either side of the body, with some individuals even having more half bands than complete ones. A series of dark brown spots is also present on the flanks, next to the belly, and are largest and darkest in the spaces between the crossbands. The belly is the same color as the ground color, but may be a little whitish in part. At the base of the tail there are 1-3 (usually 2) brown crossbands followed by a gray area. In juveniles, the pattern on the tail is more distinct: 7-9 crossbands are visible, while the tip is yellow. On the head, the crown is usually unmarked, except for a pair of small dark spots, one near the midline of each parietal scale. A faint postocular stripe is also present; diffuse above and bordered below by a narrow brown edge.
Several aberrant color patterns for A. c. contortrix, or populations that intergrade
with it, have also been reported. In a specimen described by Livezey (1949) from Walker County, Texas
, 11 of 17 crossbands were not joined middorsally, while on one side three of the crossbands were fused together longitudinally to form a continuous undulating band, surmounted above by a dark stripe that was 2-2.5 scales wide. In another specimen, from Lowndes County, Alabama
, the first three crossbands were complete, followed by a dark stripe that ran down either side of the body, with points of pigment reaching up to the midline in six places but never getting there, after which the last four crossbands on the tail were also complete. A specimen found in Terrebonne Parish, Louisiana
by Ernest A. Liner, had a similar striped pattern, with only the first and last two crossbands being normal.
).
in the states of Alabama
, Arkansas
, Connecticut
, Delaware
, Florida
, Georgia
, Illinois
, Indiana
, Iowa
, Kansas
, Kentucky
, Louisiana
, Texas
, Ohio
, Oklahoma
, Maryland
, Massachusetts
, Mississippi
, Missouri
, New Jersey
, New York, North Carolina
, Pennsylvania
, South Carolina
, Tennessee
, Virginia
and West Virginia
. In Mexico
it occurs in Chihuahua and Coahuila
. The type locality is "Carolina." Schmidt (1953) proposed that the type locality be restricted to "Charleston, South Carolina."
Unlike some other species
of North American
pit vipers, such as Crotalus horridus
and Sistrurus catenatus
, Agkistrodon contortrix has not reestablished itself north of the terminal moraine
after the last glacial period (the Wisconsin glaciation
).
it favors deciduous forest
and mixed woodlands. It is often associated with rock outcroppings and ledges, but is also found in low-lying swampy regions. During the winter it hibernates in dens, in limestone crevices, often together with Timber Rattlesnakes and Black Rat Snake
s. In the states around the Gulf of Mexico
, however, this species is also found in coniferous forest. In the Chihuahuan Desert
of west Texas
and northern Mexico
, it occurs in riparian habitats
, usually near permanent or semipermanent water and sometimes in dry arroyos
(brooks).
Red List of Threatened Species
(v3.1, 2001). Species are listed as such due to their wide distribution, presumed large population, or because it is unlikely to be declining fast enough to qualify for listing in a more threatened category. The population trend is stable. Year assessed: 2007.
, A. contortrix is generally an ambush predator: it takes up a promising position and waits for suitable prey to arrive. One exception to ambush foraging occurs when copperheads feed on insects such as caterpillars and freshly molted cicadas. When hunting insects, copperheads actively pursue their prey. Juveniles use a brightly colored tail to attract frogs and perhaps lizards, a behavior termed caudal luring
(see video: http://www.open2it.com/videos/62-animal-behavior/160-caudal-luring-in-the-copperhead.html). In the southern United States
, they are nocturnal during the hot summer months, but are commonly active during the day during the spring and fall.
Like most North American viperids, these snakes prefer to avoid humans and, given the opportunity, will leave the area without biting. However, unlike other viperids they will often "freeze" instead of slithering away, and as a result many bites occur from people unknowingly stepping on or near them. This tendency to freeze likely evolved because of the extreme effectiveness of their camouflage. When lying on dead leaves or red clay they can be almost impossible to notice. They will frequently stay still even when approached closely, and will generally strike only if physical contact is made.
s. They have also shown fondness for large insects and frogs, and though highly terrestrial
, have been known to climb trees to gorge on emerging cicadas.
A study has shown that A. contortrix males have longer tongue tine lengths than females during the breeding season which may aid in chemoreception of males searching for females.
. Copperheads often employ a "warning bite" when stepped on or agitated and inject a relatively small amount of venom, if any at all. "Dry bites" involving no venom are particularly common with the copperhead, though all pit vipers are capable of a dry bite.
Bite symptoms include intense pain, tingling, throbbing, swelling, and severe nausea. Damage can occur to muscle and bone tissue, especially when the bite occurs in the outer extremities such as the hands and feet, areas in which there is not a large muscle mass to absorb the venom. A bite from any venomous snake should be taken very seriously and immediate medical attention sought, as allergic reaction and secondary infection are always possible.
The venom of the Southern copperhead has been found to hold a protein called "Contortrostatin" that halts the growth of cancer cells and also stops the migration of the tumors to other sites. It will probably be ten or more years before contortrostatin is used in practical treatment but it has shown to be a very promising drug in laboratory studies.
Although technically the antivenin
CroFab
could be used to treat an envenomation, it is usually not administered for copperheads, as the risk of complications of an allergic reaction to the treatment are greater than the risk from the snakebite itself in most cases. Pain management
, antibiotics, and medical supervision in the case of complications is usually the course of action. In 2002 the Illinois poison control center report on the availability of antivenin, the report stated it used 1 Acp to 5 Acp depending on the symptoms and circumstances. The symptoms of a mild envenomation include swelling of the hand, mild cellulitis, and respiratory distress. The symptoms of a moderate envenomation would include swelling of the hand, vomiting, mild bleeding, ecchymosis, diaphoretic, sinus tachycardia, and hypotensive, where the most likely circumstance is the person bitten was collecting rocks.
Venomous snake
"Poisonous snake" redirects here. For true poisonous snakes, see Rhabdophis.Venomous snakes are snakes which have venom glands and specialized teeth for the injection of venom...
found in North America
North America
North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...
, a member of the Crotalinae (pit viper)
Crotalinae
The Crotalinae, commonly known as "pit vipers" or crotaline snakes, are a subfamily of venomous vipers found in Asia and the Americas. They are distinguished by the presence of a heat-sensing pit organ located between the eye and the nostril on either side of the head...
subfamily. The more common name for the species is "copperhead". The behavior of 'Agkistrodon contortrix' may lead to accidental encounters with humans. Five subspecies
Subspecies
Subspecies in biological classification, is either a taxonomic rank subordinate to species, ora taxonomic unit in that rank . A subspecies cannot be recognized in isolation: a species will either be recognized as having no subspecies at all or two or more, never just one...
are currently recognized, including the nominate subspecies described here.
Description
Adults usually grow to a total length of 50–95 cm (19.7–37.4 in), although some may exceed 1 m (3.3 ft). Males are usually larger than females. The maximum length reported for this species is 134.6 cm (53 in) for A. c. mokasenAgkistrodon contortrix mokasen
Agkistrodon contortrix mokasen is a venomous pitviper subspecies found in the eastern United States.-Description:The Northern copperhead grows to an average length of 61-91 cm , with a maximum of 134.6 cm ....
(Ditmars, 1931). Brimley (1944) mentions a specimen of A. c. mokasen from Chapel Hill, North Carolina
Chapel Hill, North Carolina
Chapel Hill is a town in Orange County, North Carolina, United States and the home of the University of North Carolina at Chapel Hill and UNC Health Care...
, that was "four feet, six inches" (137.2 cm), but this may have been an approximation. The maximum length for A. c. contortrix is 132.1 cm (52 in) (Conant, 1958).
The body is relatively stout and the head is broad and distinct from the neck. Because the snout slopes down and back, it appears less blunt than that of the cottonmouth, A. piscivorus
Agkistrodon piscivorus
Agkistrodon piscivorus is a venomous snake, a species of pit viper, found in the southeastern United States. Adults are large and capable of delivering a painful and potentially fatal bite. When antagonized they will stand their ground by coiling their bodies and displaying their fangs...
. Consequently, the top of the head extends further forward than the mouth.
The scalation includes 21-25 (usually 23) rows of dorsal scales
Dorsal scales
In snakes, the dorsal scales are the longitudinal series of plates that encircle the body, but do not include the ventral scales.When counting dorsal scales, numbers are often given for three points along the body, for example 19:21:17...
at midbody, 138-157 ventral scales
Ventral scales
In snakes, the ventral scales are the enlarged and transversely elongated scales that extend down the underside of the body from the neck to the anal scale. When counting them, the first is the anteriormost ventral scale that contacts the paraventral row of dorsal scales on either side...
in both sexes and 38-62/37-57 subcaudal scales
Subcaudal scales
In snakes, the subcaudal scales are the enlarged plates on the underside of the tail. These scales may be either single or divided and are preceded by the anal scale....
in males/females. The subcaudals are usually single, but the percentage thereof decreases clinally from the northeast, where about 80% are undivided, to the southwest of the geographic range where as little as 50% may be undivided. On the head there are usually 9 large symmetrical plates, 6-10 (usually 8) supralabial scales
Supralabial scales
In reptiles, the supralabial scales, also called upper-labials, are those scales that border the mouth opening along the upper jaw. They do not include the median scale . The term labial originates from Labium , which refers to any lip-like structure...
and 8-13 (usually 10) sublabial scales
Sublabial scales
In reptiles, the sublabial scales, also called lower-labials or infralabials, are those scales that border the mouth opening along the lower jaw. They do not include the median scale . The term labial originates from Labium , which refers to any lip-like structure...
.
The color pattern consists of a pale tan to pinkish tan ground color that becomes darker towards the midline, overlaid with a series of 10-18 (13.4) crossbands. Characteristically, both the ground color and crossband pattern are pale in A. c. contortrix. These crossbands are light tan to pinkish tan to pale brown in the center, but darker towards the edges. They are about 2 scales wide or less at the midline of the back, but expand to a width of 6-10 scales on the sides of the body. They do not extend down to the ventral scales. Often, the crossbands are divided at the midline and alternate on either side of the body, with some individuals even having more half bands than complete ones. A series of dark brown spots is also present on the flanks, next to the belly, and are largest and darkest in the spaces between the crossbands. The belly is the same color as the ground color, but may be a little whitish in part. At the base of the tail there are 1-3 (usually 2) brown crossbands followed by a gray area. In juveniles, the pattern on the tail is more distinct: 7-9 crossbands are visible, while the tip is yellow. On the head, the crown is usually unmarked, except for a pair of small dark spots, one near the midline of each parietal scale. A faint postocular stripe is also present; diffuse above and bordered below by a narrow brown edge.
Several aberrant color patterns for A. c. contortrix, or populations that intergrade
Intergradation
In zoology, intergradation is the way in which two distinct subspecies are connected via areas where populations are found that have the characteristics of both...
with it, have also been reported. In a specimen described by Livezey (1949) from Walker County, Texas
Walker County, Texas
Walker County is a county located in the U.S. state of Texas. In 2010, its population was 67,861. Its county seat is Huntsville.Initially, Walker County was named for Robert J. Walker, a legislator from Mississippi who introduced into the United States Congress the resolution to annex Texas...
, 11 of 17 crossbands were not joined middorsally, while on one side three of the crossbands were fused together longitudinally to form a continuous undulating band, surmounted above by a dark stripe that was 2-2.5 scales wide. In another specimen, from Lowndes County, Alabama
Lowndes County, Alabama
Lowndes County is a county of the U.S. state of Alabama. It is named in honor of William Lowndes, a member of the United States Congress from South Carolina. As of the 2010 census, the population was 11,299...
, the first three crossbands were complete, followed by a dark stripe that ran down either side of the body, with points of pigment reaching up to the midline in six places but never getting there, after which the last four crossbands on the tail were also complete. A specimen found in Terrebonne Parish, Louisiana
Terrebonne Parish, Louisiana
Terrebonne Parish is a parish located in the U.S. state of Louisiana. The parish seat is Houma. Its population was 111,860...
by Ernest A. Liner, had a similar striped pattern, with only the first and last two crossbands being normal.
Common names
Copperhead (snake), chunk head, death adder, highland moccasin, (dry-land) moccasin, narrow-banded copperhead, northern copperhead, pilot snake, poplar leaf, red oak, red snake, southeastern copperhead, white oak snake, American copperhead, southern copperhead, cantil cobrizo (SpanishSpanish language
Spanish , also known as Castilian , is a Romance language in the Ibero-Romance group that evolved from several languages and dialects in central-northern Iberia around the 9th century and gradually spread with the expansion of the Kingdom of Castile into central and southern Iberia during the...
).
Geographic range
Found in the United StatesUnited States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
in the states of Alabama
Alabama
Alabama is a state located in the southeastern region of the United States. It is bordered by Tennessee to the north, Georgia to the east, Florida and the Gulf of Mexico to the south, and Mississippi to the west. Alabama ranks 30th in total land area and ranks second in the size of its inland...
, Arkansas
Arkansas
Arkansas is a state located in the southern region of the United States. Its name is an Algonquian name of the Quapaw Indians. Arkansas shares borders with six states , and its eastern border is largely defined by the Mississippi River...
, Connecticut
Connecticut
Connecticut is a state in the New England region of the northeastern United States. It is bordered by Rhode Island to the east, Massachusetts to the north, and the state of New York to the west and the south .Connecticut is named for the Connecticut River, the major U.S. river that approximately...
, Delaware
Delaware
Delaware is a U.S. state located on the Atlantic Coast in the Mid-Atlantic region of the United States. It is bordered to the south and west by Maryland, and to the north by Pennsylvania...
, Florida
Florida
Florida is a state in the southeastern United States, located on the nation's Atlantic and Gulf coasts. It is bordered to the west by the Gulf of Mexico, to the north by Alabama and Georgia and to the east by the Atlantic Ocean. With a population of 18,801,310 as measured by the 2010 census, it...
, Georgia
Georgia (U.S. state)
Georgia is a state located in the southeastern United States. It was established in 1732, the last of the original Thirteen Colonies. The state is named after King George II of Great Britain. Georgia was the fourth state to ratify the United States Constitution, on January 2, 1788...
, Illinois
Illinois
Illinois is the fifth-most populous state of the United States of America, and is often noted for being a microcosm of the entire country. With Chicago in the northeast, small industrial cities and great agricultural productivity in central and northern Illinois, and natural resources like coal,...
, Indiana
Indiana
Indiana is a US state, admitted to the United States as the 19th on December 11, 1816. It is located in the Midwestern United States and Great Lakes Region. With 6,483,802 residents, the state is ranked 15th in population and 16th in population density. Indiana is ranked 38th in land area and is...
, Iowa
Iowa
Iowa is a state located in the Midwestern United States, an area often referred to as the "American Heartland". It derives its name from the Ioway people, one of the many American Indian tribes that occupied the state at the time of European exploration. Iowa was a part of the French colony of New...
, Kansas
Kansas
Kansas is a US state located in the Midwestern United States. It is named after the Kansas River which flows through it, which in turn was named after the Kansa Native American tribe, which inhabited the area. The tribe's name is often said to mean "people of the wind" or "people of the south...
, Kentucky
Kentucky
The Commonwealth of Kentucky is a state located in the East Central United States of America. As classified by the United States Census Bureau, Kentucky is a Southern state, more specifically in the East South Central region. Kentucky is one of four U.S. states constituted as a commonwealth...
, Louisiana
Louisiana
Louisiana is a state located in the southern region of the United States of America. Its capital is Baton Rouge and largest city is New Orleans. Louisiana is the only state in the U.S. with political subdivisions termed parishes, which are local governments equivalent to counties...
, Texas
Texas
Texas is the second largest U.S. state by both area and population, and the largest state by area in the contiguous United States.The name, based on the Caddo word "Tejas" meaning "friends" or "allies", was applied by the Spanish to the Caddo themselves and to the region of their settlement in...
, Ohio
Ohio
Ohio is a Midwestern state in the United States. The 34th largest state by area in the U.S.,it is the 7th‑most populous with over 11.5 million residents, containing several major American cities and seven metropolitan areas with populations of 500,000 or more.The state's capital is Columbus...
, Oklahoma
Oklahoma
Oklahoma is a state located in the South Central region of the United States of America. With an estimated 3,751,351 residents as of the 2010 census and a land area of 68,667 square miles , Oklahoma is the 28th most populous and 20th-largest state...
, Maryland
Maryland
Maryland is a U.S. state located in the Mid Atlantic region of the United States, bordering Virginia, West Virginia, and the District of Columbia to its south and west; Pennsylvania to its north; and Delaware to its east...
, Massachusetts
Massachusetts
The Commonwealth of Massachusetts is a state in the New England region of the northeastern United States of America. It is bordered by Rhode Island and Connecticut to the south, New York to the west, and Vermont and New Hampshire to the north; at its east lies the Atlantic Ocean. As of the 2010...
, Mississippi
Mississippi
Mississippi is a U.S. state located in the Southern United States. Jackson is the state capital and largest city. The name of the state derives from the Mississippi River, which flows along its western boundary, whose name comes from the Ojibwe word misi-ziibi...
, Missouri
Missouri
Missouri is a US state located in the Midwestern United States, bordered by Iowa, Illinois, Kentucky, Tennessee, Arkansas, Oklahoma, Kansas and Nebraska. With a 2010 population of 5,988,927, Missouri is the 18th most populous state in the nation and the fifth most populous in the Midwest. It...
, New Jersey
New Jersey
New Jersey is a state in the Northeastern and Middle Atlantic regions of the United States. , its population was 8,791,894. It is bordered on the north and east by the state of New York, on the southeast and south by the Atlantic Ocean, on the west by Pennsylvania and on the southwest by Delaware...
, New York, North Carolina
North Carolina
North Carolina is a state located in the southeastern United States. The state borders South Carolina and Georgia to the south, Tennessee to the west and Virginia to the north. North Carolina contains 100 counties. Its capital is Raleigh, and its largest city is Charlotte...
, Pennsylvania
Pennsylvania
The Commonwealth of Pennsylvania is a U.S. state that is located in the Northeastern and Mid-Atlantic regions of the United States. The state borders Delaware and Maryland to the south, West Virginia to the southwest, Ohio to the west, New York and Ontario, Canada, to the north, and New Jersey to...
, South Carolina
South Carolina
South Carolina is a state in the Deep South of the United States that borders Georgia to the south, North Carolina to the north, and the Atlantic Ocean to the east. Originally part of the Province of Carolina, the Province of South Carolina was one of the 13 colonies that declared independence...
, Tennessee
Tennessee
Tennessee is a U.S. state located in the Southeastern United States. It has a population of 6,346,105, making it the nation's 17th-largest state by population, and covers , making it the 36th-largest by total land area...
, Virginia
Virginia
The Commonwealth of Virginia , is a U.S. state on the Atlantic Coast of the Southern United States. Virginia is nicknamed the "Old Dominion" and sometimes the "Mother of Presidents" after the eight U.S. presidents born there...
and West Virginia
West Virginia
West Virginia is a state in the Appalachian and Southeastern regions of the United States, bordered by Virginia to the southeast, Kentucky to the southwest, Ohio to the northwest, Pennsylvania to the northeast and Maryland to the east...
. In Mexico
Mexico
The United Mexican States , commonly known as Mexico , is a federal constitutional republic in North America. It is bordered on the north by the United States; on the south and west by the Pacific Ocean; on the southeast by Guatemala, Belize, and the Caribbean Sea; and on the east by the Gulf of...
it occurs in Chihuahua and Coahuila
Coahuila
Coahuila, formally Coahuila de Zaragoza , officially Estado Libre y Soberano de Coahuila de Zaragoza is one of the 31 states which, with the Federal District, comprise the 32 Federal Entities of Mexico...
. The type locality is "Carolina." Schmidt (1953) proposed that the type locality be restricted to "Charleston, South Carolina."
Unlike some other species
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...
of North American
North America
North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...
pit vipers, such as Crotalus horridus
Crotalus horridus
Crotalus horridus, the timber rattlesnake, is a species of venomous pitviper found in the eastern United States. This is the only rattlesnake species in most of the populous northeastern United States. No subspecies are currently recognized....
and Sistrurus catenatus
Sistrurus catenatus
Sistrurus catenatus is a venomous pitviper species found primarily in the United States. Three subspecies are currently recognized, including the nominate subspecies described here.-Description:...
, Agkistrodon contortrix has not reestablished itself north of the terminal moraine
Terminal moraine
A terminal moraine, also called end moraine, is a moraine that forms at the end of the glacier called the snout.Terminal moraines mark the maximum advance of the glacier. An end moraine is at the present boundary of the glacier....
after the last glacial period (the Wisconsin glaciation
Wisconsin glaciation
The last glacial period was the most recent glacial period within the current ice age occurring during the last years of the Pleistocene, from approximately 110,000 to 10,000 years ago....
).
Habitat
Within its range it occupies a variety of different habitats. In most of North AmericaNorth America
North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...
it favors deciduous forest
Deciduous
Deciduous means "falling off at maturity" or "tending to fall off", and is typically used in reference to trees or shrubs that lose their leaves seasonally, and to the shedding of other plant structures such as petals after flowering or fruit when ripe...
and mixed woodlands. It is often associated with rock outcroppings and ledges, but is also found in low-lying swampy regions. During the winter it hibernates in dens, in limestone crevices, often together with Timber Rattlesnakes and Black Rat Snake
Black Rat Snake
The Western ratsnake — also called black rat snake, pilot black snake, or simply black snake — is a nonvenomous colubrid species found in North America. No subspecies are currently recognized....
s. In the states around the Gulf of Mexico
Gulf of Mexico
The Gulf of Mexico is a partially landlocked ocean basin largely surrounded by the North American continent and the island of Cuba. It is bounded on the northeast, north and northwest by the Gulf Coast of the United States, on the southwest and south by Mexico, and on the southeast by Cuba. In...
, however, this species is also found in coniferous forest. In the Chihuahuan Desert
Chihuahuan Desert
The Chihuahuan Desert is a desert, and an ecoregion designation, that straddles the U.S.-Mexico border in the central and northern portions of the Mexican Plateau, bordered on the west by the extensive Sierra Madre Occidental range, and overlaying northern portions of the east range, the Sierra...
of west Texas
Texas
Texas is the second largest U.S. state by both area and population, and the largest state by area in the contiguous United States.The name, based on the Caddo word "Tejas" meaning "friends" or "allies", was applied by the Spanish to the Caddo themselves and to the region of their settlement in...
and northern Mexico
Mexico
The United Mexican States , commonly known as Mexico , is a federal constitutional republic in North America. It is bordered on the north by the United States; on the south and west by the Pacific Ocean; on the southeast by Guatemala, Belize, and the Caribbean Sea; and on the east by the Gulf of...
, it occurs in riparian habitats
Riparian zone
A riparian zone or riparian area is the interface between land and a river or stream. Riparian is also the proper nomenclature for one of the fifteen terrestrial biomes of the earth. Plant habitats and communities along the river margins and banks are called riparian vegetation, characterized by...
, usually near permanent or semipermanent water and sometimes in dry arroyos
Arroyo (creek)
An arroyo , a Spanish word translated as brook, and also called a wash is usually a dry creek or stream bed—gulch that temporarily or seasonally fills and flows after sufficient rain. Wadi is a similar term in Africa. In Spain, a rambla has a similar meaning to arroyo.-Types and processes:Arroyos...
(brooks).
Conservation status
This species is classified as Least Concern (LC) on the IUCNWorld Conservation Union
The International Union for Conservation of Nature and Natural Resources is an international organization dedicated to finding "pragmatic solutions to our most pressing environment and development challenges." The organization publishes the IUCN Red List, compiling information from a network of...
Red List of Threatened Species
IUCN Red List
The IUCN Red List of Threatened Species , founded in 1963, is the world's most comprehensive inventory of the global conservation status of biological species. The International Union for Conservation of Nature is the world's main authority on the conservation status of species...
(v3.1, 2001). Species are listed as such due to their wide distribution, presumed large population, or because it is unlikely to be declining fast enough to qualify for listing in a more threatened category. The population trend is stable. Year assessed: 2007.
Behavior
Like all pit vipersCrotalinae
The Crotalinae, commonly known as "pit vipers" or crotaline snakes, are a subfamily of venomous vipers found in Asia and the Americas. They are distinguished by the presence of a heat-sensing pit organ located between the eye and the nostril on either side of the head...
, A. contortrix is generally an ambush predator: it takes up a promising position and waits for suitable prey to arrive. One exception to ambush foraging occurs when copperheads feed on insects such as caterpillars and freshly molted cicadas. When hunting insects, copperheads actively pursue their prey. Juveniles use a brightly colored tail to attract frogs and perhaps lizards, a behavior termed caudal luring
Caudal luring
Caudal luring is the use of tail movements employed by a predator to attract prey animals. It is a form of mimicry classified formally as aggressive mimicry, but perhaps better described by the term feeding mimicry. The behavior is employed by a number of snake species and allegedly by two lizards,...
(see video: http://www.open2it.com/videos/62-animal-behavior/160-caudal-luring-in-the-copperhead.html). In the southern United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
, they are nocturnal during the hot summer months, but are commonly active during the day during the spring and fall.
Like most North American viperids, these snakes prefer to avoid humans and, given the opportunity, will leave the area without biting. However, unlike other viperids they will often "freeze" instead of slithering away, and as a result many bites occur from people unknowingly stepping on or near them. This tendency to freeze likely evolved because of the extreme effectiveness of their camouflage. When lying on dead leaves or red clay they can be almost impossible to notice. They will frequently stay still even when approached closely, and will generally strike only if physical contact is made.
Feeding
Roughly 90% of its diet consists of small rodents, such as mice and voleVole
A vole is a small rodent resembling a mouse but with a stouter body, a shorter hairy tail, a slightly rounder head, smaller ears and eyes, and differently formed molars . There are approximately 155 species of voles. They are sometimes known as meadow mice or field mice in North America...
s. They have also shown fondness for large insects and frogs, and though highly terrestrial
Terrestrial animal
Terrestrial animals are animals that live predominantly or entirely on land , as compared with aquatic animals, which live predominantly or entirely in the water , or amphibians, which rely on a combination of aquatic and terrestrial habitats...
, have been known to climb trees to gorge on emerging cicadas.
Reproduction
A. contortrix breeds in late summer, but not every year: sometimes a female will produce young for several years running, then not breed at all for a time. They give birth to live young about 20 cm long: a typical litter is 4 to 7, but it can be as few as one or as many as 20. Their size apart, the young are similar to the adults, but lighter in color, and with a yellow-marked tip to the tail, which is used to lure lizards and frogs.A study has shown that A. contortrix males have longer tongue tine lengths than females during the breeding season which may aid in chemoreception of males searching for females.
Venom
Although venomous, these snakes are generally non-aggressive and bites are almost never fatal. Copperhead venom has an estimated lethal dose of around 100 mg, and tests on mice show its potency is among the lowest of all pit vipers, and slightly weaker than that of its close relative, the cottonmouthAgkistrodon piscivorus
Agkistrodon piscivorus is a venomous snake, a species of pit viper, found in the southeastern United States. Adults are large and capable of delivering a painful and potentially fatal bite. When antagonized they will stand their ground by coiling their bodies and displaying their fangs...
. Copperheads often employ a "warning bite" when stepped on or agitated and inject a relatively small amount of venom, if any at all. "Dry bites" involving no venom are particularly common with the copperhead, though all pit vipers are capable of a dry bite.
Bite symptoms include intense pain, tingling, throbbing, swelling, and severe nausea. Damage can occur to muscle and bone tissue, especially when the bite occurs in the outer extremities such as the hands and feet, areas in which there is not a large muscle mass to absorb the venom. A bite from any venomous snake should be taken very seriously and immediate medical attention sought, as allergic reaction and secondary infection are always possible.
The venom of the Southern copperhead has been found to hold a protein called "Contortrostatin" that halts the growth of cancer cells and also stops the migration of the tumors to other sites. It will probably be ten or more years before contortrostatin is used in practical treatment but it has shown to be a very promising drug in laboratory studies.
Although technically the antivenin
Antivenin
Antivenom is a biological product used in the treatment of venomous bites or stings. Antivenom is created by milking venom from the desired snake, spider or insect. The venom is then diluted and injected into a horse, sheep or goat...
CroFab
CroFab
CroFab is the commercial name for a Crotalidae Polyvalent Immune Fab snake antivenom, indicated for minimal or moderate North American Crotalid snake envenomation. It is developed and manufactured by BTG plc , and distributed in the US by Nycomed Inc...
could be used to treat an envenomation, it is usually not administered for copperheads, as the risk of complications of an allergic reaction to the treatment are greater than the risk from the snakebite itself in most cases. Pain management
Pain management
Pain management is a branch of medicine employing an interdisciplinary approach for easing the suffering and improving the quality of life of those living with pain. The typical pain management team includes medical practitioners, clinical psychologists, physiotherapists, occupational therapists,...
, antibiotics, and medical supervision in the case of complications is usually the course of action. In 2002 the Illinois poison control center report on the availability of antivenin, the report stated it used 1 Acp to 5 Acp depending on the symptoms and circumstances. The symptoms of a mild envenomation include swelling of the hand, mild cellulitis, and respiratory distress. The symptoms of a moderate envenomation would include swelling of the hand, vomiting, mild bleeding, ecchymosis, diaphoretic, sinus tachycardia, and hypotensive, where the most likely circumstance is the person bitten was collecting rocks.
Subspecies
| Subspecies | Taxon author | Common name | Geographic range |
|---|---|---|---|
| A. c. contortrix | (Linnaeus Carolus Linnaeus Carl Linnaeus , also known after his ennoblement as , was a Swedish botanist, physician, and zoologist, who laid the foundations for the modern scheme of binomial nomenclature. He is known as the father of modern taxonomy, and is also considered one of the fathers of modern ecology... , 1766) |
Southern copperhead | The United States United States The United States of America is a federal constitutional republic comprising fifty states and a federal district... , in the lower Mississippi Valley and the states bordering the Gulf of Mexico Gulf of Mexico The Gulf of Mexico is a partially landlocked ocean basin largely surrounded by the North American continent and the island of Cuba. It is bounded on the northeast, north and northwest by the Gulf Coast of the United States, on the southwest and south by Mexico, and on the southeast by Cuba. In... , from eastern Texas Texas Texas is the second largest U.S. state by both area and population, and the largest state by area in the contiguous United States.The name, based on the Caddo word "Tejas" meaning "friends" or "allies", was applied by the Spanish to the Caddo themselves and to the region of their settlement in... and southeastern Oklahoma Oklahoma Oklahoma is a state located in the South Central region of the United States of America. With an estimated 3,751,351 residents as of the 2010 census and a land area of 68,667 square miles , Oklahoma is the 28th most populous and 20th-largest state... to southern Illinois Illinois Illinois is the fifth-most populous state of the United States of America, and is often noted for being a microcosm of the entire country. With Chicago in the northeast, small industrial cities and great agricultural productivity in central and northern Illinois, and natural resources like coal,... . On the South Atlantic Coastal Plain from the Florida Florida Florida is a state in the southeastern United States, located on the nation's Atlantic and Gulf coasts. It is bordered to the west by the Gulf of Mexico, to the north by Alabama and Georgia and to the east by the Atlantic Ocean. With a population of 18,801,310 as measured by the 2010 census, it... panhandle to South Carolina South Carolina South Carolina is a state in the Deep South of the United States that borders Georgia to the south, North Carolina to the north, and the Atlantic Ocean to the east. Originally part of the Province of Carolina, the Province of South Carolina was one of the 13 colonies that declared independence... . |
| A. c. laticinctus Agkistrodon contortrix laticinctus Agkistrodon contortrix laticinctus is a venomous pitviper subspecies found in the southern United States, from Kansas, through Oklahoma and throughout central Texas.-Description:... |
Gloyd & Conant Roger Conant (herpetologist) Roger Conant was an American herpetologist, author, educator and conservationist. He was Director Emeritus of the Philadelphia Zoo and Adjunct Professor at the University of New Mexico... , 1934 |
Broad-banded copperhead | The United States, from south-central Texas (Victoria Victoria County, Texas Victoria County is a county located in the U.S. state of Texas. In 2000, its population was 84,088. Its county seat is Victoria. It is included in the Victoria, Texas Metropolitan Statistical Area.-Geography:According to the U.S... to Frio counties), north through central Oklahoma to the extreme south of Cowley County, Kansas Cowley County, Kansas Cowley County is a county located in south-central Kansas, in the Central United States. As of the 2010 census, the county population was 36,311. Its county seat and most populous city is Winfield... . |
| A. c. mokasen Agkistrodon contortrix mokasen Agkistrodon contortrix mokasen is a venomous pitviper subspecies found in the eastern United States.-Description:The Northern copperhead grows to an average length of 61-91 cm , with a maximum of 134.6 cm .... |
Palisot de Beauvois Palisot de Beauvois Ambroise Marie François Joseph Palisot, Baron de Beauvois 27 July 1752 Arras - 21 January 1820 Paris, was a French naturalist.Palisot collected insects in Oware, Benin, Saint Domingue, and the United States, during the period 1786 – 1797. Trained as a botanist, Palisot published a significant... , 1799 |
Northern copperhead | The United States, in southern Illinois, northern Michigan Michigan Michigan is a U.S. state located in the Great Lakes Region of the United States of America. The name Michigan is the French form of the Ojibwa word mishigamaa, meaning "large water" or "large lake".... ,extreme northeastern Mississippi, northern Alabama Alabama Alabama is a state located in the southeastern region of the United States. It is bordered by Tennessee to the north, Georgia to the east, Florida and the Gulf of Mexico to the south, and Mississippi to the west. Alabama ranks 30th in total land area and ranks second in the size of its inland... , northern Georgia Georgia (U.S. state) Georgia is a state located in the southeastern United States. It was established in 1732, the last of the original Thirteen Colonies. The state is named after King George II of Great Britain. Georgia was the fourth state to ratify the United States Constitution, on January 2, 1788... northeast to Massachusetts Massachusetts The Commonwealth of Massachusetts is a state in the New England region of the northeastern United States of America. It is bordered by Rhode Island and Connecticut to the south, New York to the west, and Vermont and New Hampshire to the north; at its east lies the Atlantic Ocean. As of the 2010... , the Appalachian Mountain region Appalachian Mountains The Appalachian Mountains #Whether the stressed vowel is or ,#Whether the "ch" is pronounced as a fricative or an affricate , and#Whether the final vowel is the monophthong or the diphthong .), often called the Appalachians, are a system of mountains in eastern North America. The Appalachians... and associated plateaus. |
| A. c. phaeogaster Agkistrodon contortrix phaeogaster Agkistrodon contortrix phaeogaster is a venomous pitviper subspecies found in the central region of the United States.-Description:Gloyd and Conant gives maximum total lengths of 990/723 mm for males/females, while mentioning that other sources give a maximum total length for this subspecies of... |
Gloyd, 1969 | Osage copperhead | The United States, in eastern Kansas Kansas Kansas is a US state located in the Midwestern United States. It is named after the Kansas River which flows through it, which in turn was named after the Kansa Native American tribe, which inhabited the area. The tribe's name is often said to mean "people of the wind" or "people of the south... , extreme southeastern Nebraska Nebraska Nebraska is a state on the Great Plains of the Midwestern United States. The state's capital is Lincoln and its largest city is Omaha, on the Missouri River.... and a large part of Missouri Missouri Missouri is a US state located in the Midwestern United States, bordered by Iowa, Illinois, Kentucky, Tennessee, Arkansas, Oklahoma, Kansas and Nebraska. With a 2010 population of 5,988,927, Missouri is the 18th most populous state in the nation and the fifth most populous in the Midwest. It... . |
| A. c. pictigaster Agkistrodon contortrix pictigaster Agkistrodon contortrix pictigaster is a venomous pitviper subspecies found in the Trans-Pecos region of the United States, in western Texas, and northeastern Mexico.-Description:... |
Gloyd & Conant, 1943 | Trans-pecos copperhead | The United States, in western Texas from the vicinity of the Pecos Pecos River The headwaters of the Pecos River are located north of Pecos, New Mexico, United States, at an elevation of over 12,000 feet on the western slope of the Sangre de Cristo mountain range in Mora County. The river flows for through the eastern portion of that state and neighboring Texas before it... and Devils Devils River (Texas) The Devils River is a pristine, whitewater river in southwestern Texas, USA. It begins in northwest Sutton County, at , where six watercourses come together, Dry Devils River, Granger Draw, House Draw, Jackson, Flat Rock Draw, and Rough Canyon... rivers to the counties of Jeff Davis Jeff Davis County, Texas Jeff Davis County is a county in the U.S. state of Texas. It is named for Jefferson Davis, the president of the Confederate States of America. It is one of the nine counties that comprise the Trans-Pecos region of West Texas. In 2000, its population was 2,207, and 2,258 by 2009... and Presidio Presidio County, Texas Presidio County is a county located in the U.S. state of Texas. In 2000, its population was 7,304. Its county seat is Marfa. Presidio County is in the Trans-Pecos region of West Texas and is named for the ancient border settlement of Presidio del Norte.-Geography:Presidio County is triangular in... . Mexico Mexico The United Mexican States , commonly known as Mexico , is a federal constitutional republic in North America. It is bordered on the north by the United States; on the south and west by the Pacific Ocean; on the southeast by Guatemala, Belize, and the Caribbean Sea; and on the east by the Gulf of... , in northern Chihuahua and Coahuila Coahuila Coahuila, formally Coahuila de Zaragoza , officially Estado Libre y Soberano de Coahuila de Zaragoza is one of the 31 states which, with the Federal District, comprise the 32 Federal Entities of Mexico... . |
Gallery
| Habitats | Isolated | Closeups |
|---|---|---|
 |
||
| Broad-banded copperhead | Southern Copperhead | St. Louis Zoo Saint Louis Zoological Park The Saint Louis Zoological Park, commonly known as the St. Louis Zoo, is a zoo in Forest Park in St. Louis, Missouri. It is recognized as a leading zoo in animal management, research, conservation, and education... |
 |
||
| Copperhead crossing river in Virginia Beach |
Southern Copperhead in Covington, Georgia Covington, Georgia Covington is a city in Newton County, Georgia, United States. As of the 2010 census, the city had a population of 13,118. The city is the county seat of Newton County... , at Bert Adams Scout Reservation |
Northern copperhead |
| Southern copperhead, near a cicada Cicada A cicada is an insect of the order Hemiptera, suborder Auchenorrhyncha , in the superfamily Cicadoidea, with large eyes wide apart on the head and usually transparent, well-veined wings. There are about 2,500 species of cicada around the world, and many of them remain unclassified... (in Arkansas) |
Southern copperhead consuming cicada (Arkansas) |
Southern copperhead close up (in Arkansas Arkansas Arkansas is a state located in the southern region of the United States. Its name is an Algonquian name of the Quapaw Indians. Arkansas shares borders with six states , and its eastern border is largely defined by the Mississippi River... ) |
Popular culture
- During the American Civil WarAmerican Civil WarThe American Civil War was a civil war fought in the United States of America. In response to the election of Abraham Lincoln as President of the United States, 11 southern slave states declared their secession from the United States and formed the Confederate States of America ; the other 25...
the leading Peace Democrats were called CopperheadsCopperheads (politics)The Copperheads were a vocal group of Democrats in the Northern United States who opposed the American Civil War, wanting an immediate peace settlement with the Confederates. Republicans started calling anti-war Democrats "Copperheads," likening them to the venomous snake...
.
- In the movie, CopperheadCopperhead (film)-Plot:The film, set just after the U.S. Civil War, begins with an outlaw named Wild Bill riding onto an apparent battlefield; he finds an elderly Mexican who, asked what happened, replies "La Serpienta Del Diablo." Bill then walks to a carriage, a woman falls out, a copperhead slithers out, and...
, A small town in the Wild West is attacked by thousands of Copperheads.
- In 2010, small arms maker Sig Sauer named a limited edition .380ACP pistol P238 Copperhead. (http://www.sigsauer.com/Products/ShowCatalogProductDetails.aspx?categoryid=67&productid=304)
External links
- Reclining With Vipers at Robert Winkler's homepage. Accessed 15 June 2007.
- Copperhead - Agkistrodon contortrix at Herpnet.net, Reptiles and Amphibians of Iowa. Accessed 15 June 2007.
- Copperhead - bites, habitats & life-cycle Accessed 15 June 2007.
- A. c. contortrix image at Glades Herp. Accessed 9 August 2007.
