Crotalus adamanteusEastern Diamondback Rattlesnake

Geographic Range

Eastern diamondback rattlesnakes (Crotalus adamanteus) can be found in the Coastal Plain of the southeastern United States. Eastern diamondbacks can be found from the eastern part of Louisiana east along the coast through Florida, and they can also be found as far north as southern North Carolina. ("Petition to list the eastern diamondback rattlesnake (Crotalus adamanteus) as threatened under the Endangered Species Act", 2011; Gibbons and Dorcas, 2005; Hoss, et al., 2010; Steen, et al., 2007)

Habitat

Eastern diamondbacks can be found scattered through the underbrush of many open abandoned fields, palmetto flat lands, pine woods, and other brush filled or grassy areas. Eastern diamondbacks stay mainly around travel game trails and other areas where they can find high concentrations of food. These snakes can be found from elevations around sea level (0m) to about 500m above sea level. They once thrived in a habitat referred to as longleaf pine (Pinus palustris) savannas, but with the decline of that habitat, the population of eastern diamondbacks has declined immensely. ("A status assessment and distribution model for the eastern diamondback rattlesnake (Crotalus adamanteus) in Georgia", 2015; "Florida's venomous snakes", 2004; "Petition to list the eastern diamondback rattlesnake (Crotalus adamanteus) as threatened under the Endangered Species Act", 2011; Ernst and Ernst, 2012; Hoss, et al., 2010; Steen, et al., 2007)

  • Range elevation
    0 to 500 m
    0.00 to 1640.42 ft

Physical Description

Eastern diamondbacks are the largest of all rattlesnakes; often described as bulky, adults in the wild weigh 2.2 to 7 kg. Most eastern diamondbacks are normally about 1.0-1.5m long, but some can grow to longer than 2.4m. Males are generally larger than females.

Scales are keeled and pitted, and colors are olive green, brown, and almost black with diamond-shaped outlines. They have tan/yellow scales and blackish brown scales that make up the inside of the diamonds. These diamonds can be found along the dorsal side of the body, and are the reason for their common name. The ventral side of the body is normally a yellowish-tan color with poorly-defined dark bands closer to the tail. Their eyes possess a vertical pupil.

Like all pit vipers, they have pits between their eyes and nostrils, a large spade-shaped head, and solenoglyphous fangs (fangs that are hinged and fold back up into the mouth). Eastern diamondbacks have two lines extending from the posterior of their eyes to the posterior of their jaws.

Their most defining trait is their rattle at the end of their tail that they shake to warn predators when they feel threatened. They gain a section of their rattle every time they shed and are born with their first section of rattle.

Size at hatching is typically 0.3 m. Hatchling diamondbacks closely resemble fully-grown diamondbacks in color and pattern. ("Florida's venomous snakes", 2004; "Petition to list the eastern diamondback rattlesnake (Crotalus adamanteus) as threatened under the Endangered Species Act", 2011; Ernst and Ernst, 2012; Gray, 2005)

  • Range mass
    2.2 to 7 kg
    4.85 to 15.42 lb
  • Range length
    1 to 2.4 m
    3.28 to 7.87 ft

Development

Female eastern diamondback rattlesnakes are ovoviviparous, which means they carry their eggs inside their body and maintain the eggs' temperature until they hatch. Neonate diamondbacks have a "button" on the end of their tail when born that eventually becomes their rattle. They shed about 3-4 times per year and gain a new segment for each shed.

At birth, neonate diamondbacks are about 30 cm long, growing steadily and reaching maturity around 3 years or about 100 cm for females and about 125 cm for males. After they reach maturity, their growth rate greatly slows but they exhibit indeterminate growth. (Ernst and Ernst, 2012; Gibbons, 2000)

Reproduction

Eastern diamondbacks mate from early August through September in the northern part of their range, and from early October through December in the southernmost part of their range (mainly southern Florida). Males will travel long distances in search of mates during the breeding season, tracking the females by their pheromone trails. Although it is not recorded how far males will travel to breed Ernst and Ernst (2012) recorded that females will shorten their daily movements as they release their pheromones. Eastern diamondbacks are polygynandrous. Males and females copulate for hours at a time by the male laying on top of the female. After breeding is finished the male will leave. Females give birth from mid-July through mid-October. Females exhibit a relatively long gestation period (120 to 180 days). Females also can store semen for up to five years until the physiological conditions are suitable for fertilization. (Ernst and Ernst, 2012; Fill, et al., 2015)

Eastern diamondbacks achieve reproductive maturity between 2 and 4 years for females and between 2.5 and 3.5 years for males. All eastern diamondbacks reproduce sexually. They breed once a year usually early August through September in the northern area of their range and early October through December in the southern part (south Florida). Their normal gestation period is 120 to 180 days.They can store semen for fertilization for almost 5 years. Most young are born from mid-July to late October. Eastern diamondbacks are ovoviviparous, which means they keep their egg clutch inside of them until they hatch. They have a median clutch size of about 18 (range 4-32). Most neonates have an average mass between 35 and 48.5 g and they are born at total lengths typically 12 cm or greater. Most neonates leave their place of birth 10 to 20 days after birth, usually after ecdysis or shedding of their skin. (Ernst and Ernst, 2012; Fill, et al., 2015)

  • Breeding interval
    Eastern diamondbacks breed once a year
  • Breeding season
    August- September (north), October- December (south)
  • Range number of offspring
    4 to 32
  • Range gestation period
    120 to 180 days
  • Range time to independence
    10 to 20 days
  • Range age at sexual or reproductive maturity (female)
    2 to 4 years
  • Range age at sexual or reproductive maturity (male)
    2.5 to 3.5 years

Female eastern diamondbacks are ovoviviparous, which serves as a way to initially protect the young. Females prepare for their birthing season by increasing in weight. They care for the young by birthing them in a secluded hole normally a gopher tortoise (Gopherus polyphemus) hole or hollow log. The young stay with the female usually until they undergo ecdysis for the first time (about 10 days after birth). The young stay with the females for protection but the females are not usually seen interacting with the young. Butler et al. (1995) hypothesize that the females stay around due to short-term exhaustion from birthing. Males have no investment other than the mating process. (Butler, et al., 1995; Ernst and Ernst, 2012)

  • Parental Investment
  • female parental care
  • pre-fertilization
    • protecting
      • female
  • pre-hatching/birth
    • protecting
      • female

Lifespan/Longevity

The average lifespan for eastern diamondbacks in captivity is about 19 years with a expected minimum of 15 years. The oldest eastern diamondback recorded in captivity was 22.75 years old. Their natural lifespan in the wild is normally between 15 and 20 years. However, very few eastern diamondbacks survive past ten years due to humans killing them for their skins. ("Petition to list the eastern diamondback rattlesnake (Crotalus adamanteus) as threatened under the Endangered Species Act", 2011; Ernst and Ernst, 2012)

  • Range lifespan
    Status: captivity
    22.75 (high) years
  • Typical lifespan
    Status: wild
    15 to 20 years
  • Typical lifespan
    Status: captivity
    15 (low) years
  • Average lifespan
    Status: captivity
    19 years

Behavior

Eastern diamondback rattlesnakes are not social creatures. They don't inhabit the same holes except when they have young. Some females birth in the same hole or log until they young leave and then go their separate ways. Males fight for territory rights in a "combat dance" which establishes territories. The bouts can last up to two hours. Many of the males' and females' territories overlap, but they usually only interact directly in mating season.

These snakes hibernate for the winter months within their range from northern Florida to southern North Carolina. Unlike other rattlesnake species, they hibernate singly, and not in groups.

Eastern diamondbacks are diurnal sit-and-wait predators that lay in a tight coil for hours at a time waiting on prey. They typically sit-and-wait in shaded areas, like in the underbrush. They are mostly diurnal, but can be active any time of the day or night. At night their loreal pits detects infrared heat, allowing them to sense their surroundings. If they sense danger, they rattle their tails, generally to warn other animals of their presence. ("Petition to list the eastern diamondback rattlesnake (Crotalus adamanteus) as threatened under the Endangered Species Act", 2011; Ernst and Ernst, 2012)

  • Range territory size
    0.180 to 0.843 km^2

Home Range

Some eastern diamondback rattlesnake females and males have overlapping territories. Males usually have larger territories with an average of 0.843 square kilometers, and females have an average territorial range of 0.465 square kilometers. During mating season females' home ranges shrink to 0.18 square kilometers. ("Petition to list the eastern diamondback rattlesnake (Crotalus adamanteus) as threatened under the Endangered Species Act", 2011; Ernst and Ernst, 2012; Waldron, et al., 2006)

Communication and Perception

Like other pit vipers, eastern diamondback rattlesnakes have loreal pits, located between their eyes and nostrils. These pits allow them to detect minuscule changes in infrared heat, useful in detecting prey, and perceiving their environment. They can also use the vibrations of their tail to warn predators. These snakes also can sense the vibrations of the ground though the linkage between their inner ear (only part of the ear they posses) and their lower jaw bone. Eastern diamondbacks can both taste and smell chemical changes in the air with a simple flick of their tongue. They rely on all of these to observe and interact with their surroundings. Male snakes locate mates by tracking pheromones produced by the females. (Bakken, et al., 2012; Gibbons and Dorcas, 2005; Gibbons, 2000; Knight, 2012)

Food Habits

Juvenile eastern diamondback rattlesnakes primarily eat small mice such as the Florida mouse (Podomys floridanus) and other small rodents like rats (Rattus) or squirrels (Sciuridae). As they get larger, they begin to take on larger prey such as eastern cottontails (Sylvilagus floridanus) or marsh rabbits (Sylvilagus palustris). They normally hunt terrestrial prey on the ground but have been known to eat ground nesting birds like bobwhite quail (Colinus virginianus). In times of scarce prey, eastern diamondbacks have been known to eat carrion.

They are ambush predators and can sit-and-wait on prey for very long periods of time. After they strike, they may wait for the prey to run away and die before consuming them. They need very little caloric intake and can survive on three to four big meals per year. (Funderburg, 1968; Gibbons and Dorcas, 2005; Means, 1999; Rokyta, et al., 2012)

  • Primary Diet
  • carnivore
    • eats terrestrial vertebrates
  • Animal Foods
  • birds
  • mammals

Predation

Eastern diamondback predators include birds of prey, other snakes, mammals, and amphibians. The predatory snakes include eastern indigo snakes (Drymarchon corais), southern black racers (Coluber constrictor priapus), common kingsnakes (Lampropeltis getula), coachwhips (Masticophis flagellum), and harlequin coralsnakes (Micrurus fulvius). Amphibian predators include American bullfrogs (Lithobates catesbeianus) and river frogs (Lithobates heckscheri). Predatory birds include great horned owls (Bubo virginianus), red-tailed hawks (Buteo jamaicensis), crested caracaras (Caracara cheriway), and wood storks (Mycteria amercana). Mammalian predators include wild hogs (Sus scrofa), raccoons (Procyon lotor), black bears (Ursus americanus), striped skunks (Mephitis mephitis), northern river otters (Lontra canadensis), domestic dogs (Canis lupus familiaris), coyotes (Canis latrans), domestic and feral cats (Felis catus), and bobcats (Lynx rufus). Eastern diamondbacks are relatively efficient at deterring these potential predators. These snakes have rattles, but they mainly stay under cover and have a pattern that blends with most low foliage and dirt. Therefore, it conceals them from birds of prey. Most animals are deterred by their rattle that is used as a warning system. This warning works due to a distinctive fear of these animals. Not many of the listed predators cause an issue for rattlesnake populations; their biggest problem is humans (Homo sapiens) who kill them for their skins and meat. ("Petition to list the eastern diamondback rattlesnake (Crotalus adamanteus) as threatened under the Endangered Species Act", 2011; Ernst and Ernst, 2012; Means, 1999)

  • Anti-predator Adaptations
  • cryptic

Ecosystem Roles

Eastern diamondback rattlesnakes are hosts to ectoparasites, such as iguana ticks (Amblyomma dissimile) and hosts to endoparasites, such as nematodes (Acaris nuda, Hexametra boddaertii), American colubrid pentastomes (Kiricephalus coarctatus), and North American porocephalus (Porocephalus crotali). As predators and prey, diamondbacks have a limited impact on their ecosystem. (Ernst and Ernst, 2012)

Commensal/Parasitic Species

Economic Importance for Humans: Positive

Many eastern diamondback rattlesnakes are caught via rattlesnake roundups an sold for skins or antivenom purposes. Some of the most common snake skin products are boots, belts, hats, and wallets. They are often caught and "milked" which is the extracting of venom for antivenom purposes. The venom is later injected into horses (Equus caballus) and other large mammals in small doses,the antivenom compounds can be derived from those mammals plasma. Due to this process the fatality rate of their bite is down to 40%. They are sometimes consumed even though there is a large risk for salmonella (Salmonella arizonae). Some eastern diamondback rattlesnakes have been sold as exotic pets in the past. ("Petition to list the eastern diamondback rattlesnake (Crotalus adamanteus) as threatened under the Endangered Species Act", 2011; Ernst and Ernst, 2012; Means, 2009)

Economic Importance for Humans: Negative

Eastern diamondback rattlesnakes affect humans negatively only because of their bite. Their venom is a hemotoxin which causes the destruction of red blood cells. Their bites have about a 40% mortality rate, leaving nearly every limb bitten permanently damaged. ("Florida's venomous snakes", 2004; Ernst and Ernst, 2012)

  • Negative Impacts
  • injures humans

Conservation Status

Eastern diamondback rattlesnakes are in the “Least Concern” category by IUCN Red List. They hold no special status under the United States Endangered Species Act. They have no special status under CITES and for the state of Michigan list (because they don't live there). Eastern diamondbacks are endangered in North Carolina, a species of special concern in South Carolina, and may be extinct in Louisiana. Outside of the Carolinas these snakes have little protection except for laws preventing the gassing of gopher tortoise (Gopherus polyphemus) holes in Florida and Georgia. The IUCN Red List states that eastern diamondback rattlesnakes are on the decline. This decline is mostly due to their loss of habitat and humans interactions. No additional conservation actions are in place for this species. ("A status assessment and distribution model for the eastern diamondback rattlesnake (Crotalus adamanteus) in Georgia", 2015; "Petition to list the eastern diamondback rattlesnake (Crotalus adamanteus) as threatened under the Endangered Species Act", 2011; Ernst and Ernst, 2012; Hammerson, 2007)

Contributors

Logan Johnson (author), Radford University, Alex Atwood (editor), Radford University, Karen Powers (editor), Radford University, Joshua Turner (editor), Radford University, Tanya Dewey (editor), University of Michigan-Ann Arbor.

Glossary

Nearctic

living in the Nearctic biogeographic province, the northern part of the New World. This includes Greenland, the Canadian Arctic islands, and all of the North American as far south as the highlands of central Mexico.

World Map

acoustic

uses sound to communicate

bilateral symmetry

having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.

carnivore

an animal that mainly eats meat

chemical

uses smells or other chemicals to communicate

cryptic

having markings, coloration, shapes, or other features that cause an animal to be camouflaged in its natural environment; being difficult to see or otherwise detect.

delayed fertilization

a substantial delay (longer than the minimum time required for sperm to travel to the egg) takes place between copulation and fertilization, used to describe female sperm storage.

diurnal
  1. active during the day, 2. lasting for one day.
drug

a substance used for the diagnosis, cure, mitigation, treatment, or prevention of disease

ectothermic

animals which must use heat acquired from the environment and behavioral adaptations to regulate body temperature

female parental care

parental care is carried out by females

food

A substance that provides both nutrients and energy to a living thing.

forest

forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.

heterothermic

having a body temperature that fluctuates with that of the immediate environment; having no mechanism or a poorly developed mechanism for regulating internal body temperature.

hibernation

the state that some animals enter during winter in which normal physiological processes are significantly reduced, thus lowering the animal's energy requirements. The act or condition of passing winter in a torpid or resting state, typically involving the abandonment of homoiothermy in mammals.

indeterminate growth

Animals with indeterminate growth continue to grow throughout their lives.

infrared/heat

(as keyword in perception channel section) This animal has a special ability to detect heat from other organisms in its environment.

iteroparous

offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).

motile

having the capacity to move from one place to another.

native range

the area in which the animal is naturally found, the region in which it is endemic.

ovoviviparous

reproduction in which eggs develop within the maternal body without additional nourishment from the parent and hatch within the parent or immediately after laying.

pet trade

the business of buying and selling animals for people to keep in their homes as pets.

polygynandrous

the kind of polygamy in which a female pairs with several males, each of which also pairs with several different females.

seasonal breeding

breeding is confined to a particular season

sedentary

remains in the same area

sexual

reproduction that includes combining the genetic contribution of two individuals, a male and a female

sexual ornamentation

one of the sexes (usually males) has special physical structures used in courting the other sex or fighting the same sex. For example: antlers, elongated tails, special spurs.

solitary

lives alone

sperm-storing

mature spermatozoa are stored by females following copulation. Male sperm storage also occurs, as sperm are retained in the male epididymes (in mammals) for a period that can, in some cases, extend over several weeks or more, but here we use the term to refer only to sperm storage by females.

tactile

uses touch to communicate

temperate

that region of the Earth between 23.5 degrees North and 60 degrees North (between the Tropic of Cancer and the Arctic Circle) and between 23.5 degrees South and 60 degrees South (between the Tropic of Capricorn and the Antarctic Circle).

territorial

defends an area within the home range, occupied by a single animals or group of animals of the same species and held through overt defense, display, or advertisement

tropical savanna and grassland

A terrestrial biome. Savannas are grasslands with scattered individual trees that do not form a closed canopy. Extensive savannas are found in parts of subtropical and tropical Africa and South America, and in Australia.

savanna

A grassland with scattered trees or scattered clumps of trees, a type of community intermediate between grassland and forest. See also Tropical savanna and grassland biome.

temperate grassland

A terrestrial biome found in temperate latitudes (>23.5° N or S latitude). Vegetation is made up mostly of grasses, the height and species diversity of which depend largely on the amount of moisture available. Fire and grazing are important in the long-term maintenance of grasslands.

venomous

an animal which has an organ capable of injecting a poisonous substance into a wound (for example, scorpions, jellyfish, and rattlesnakes).

vibrations

movements of a hard surface that are produced by animals as signals to others

visual

uses sight to communicate

References

The Orianne Society. A status assessment and distribution model for the eastern diamondback rattlesnake (Crotalus adamanteus) in Georgia. None. Clayton, Georgia: The Orianne Society. 2015. Accessed September 10, 2017 at http://georgiawildlife.com/sites/default/files/wrd/pdf/research/GaStatus_DistributionModel_EasternDiamondbackRattlesnake_Report.pdf.

Florida Fish and Wildlife Conservation Commission. Florida's venomous snakes. none. Tallahassee, FL: Florida Fish and Wildlife Conservation Commission. 2004. Accessed September 10, 2017 at http://myfwc.com/media/1321792/guide_to_venomous_snakes_in_fl.pdf.

Center for Biological Diversity, Coastal Plains institute, Protecting All Living Species, One more Generation. Petition to list the eastern diamondback rattlesnake (Crotalus adamanteus) as threatened under the Endangered Species Act. None. USA: Center for Biological Diversity, Coastal Plains institute, Protecting All Living Species, One more Generation. 2011. Accessed September 11, 2017 at https://www.fws.gov/southeast/pdf/petition/eastern-diamondback-rattlesnake.pdf.

Bakken, G., S. Colayori, T. Duong. 2012. Analytical methods for the geometric optics of thermal vision illustrated with four species of pit vipers. Journal of Experimental Biology, 215/15: 2621-2629.

Butler, J., T. Hull, R. Franz. 1995. Neonate aggregations and maternal attendance of young in the eastern diamondback rattlesnake, Crotalus adamanteus. Copeia, 1995/1: 196-198.

Ernst, C., E. Ernst. 2012. Venomous Reptiles of the United States, Canada, and Northern Mexico Volume 2, Crotalus. Baltimore, MD: The John Hopkins University Press.

Fill, J., J. Waldron, S. Welch, M. Martin, J. Cantrell, S. Bennett, W. Kalinowsky, J. Holloway, T. Mousseau. 2015. Breeding and reproductive phenology of eastern diamond-backed rattlesnakes (Crotalus adamanteus) in South Carolina. Journal of Herpetology, 49/4: 570-573.

Fitzgerald, L., C. painter. 2000. Rattlesnake commercialization: Long-term trends, issues, and implications for conservation. Wildlife Society Bulletin, 28/1: 235-253.

Funderburg, J. 1968. Eastern diamondback rattlesnake feeding on carrion. Journal of Herpetology, 2/3/4: 161-162.

Gibbons, W. 2000. Dean of America's venomous snakes - the eastern diamondback's life cycle. World and I, 15/8: 138.

Gibbons, W., M. Dorcas. 2005. Snakes of the Southeast. Athens, GA: University of Georgia Press.

Gray, B. 2005. The Serpent's Cast. Lanesboro, MN: Serpents Tale Natural History Book Distributors.

Greene, H. 1997. Snakes: The Evolution of Mystery in Nature. Berkeley, CA: University of California press.

Hammerson, G. 2007. "Crotalus adamanteus" (On-line). The IUCN Red List of Threatened Species 2007 e.T64308A12762249. Accessed November 02, 2017 at http://www.iucnredlist.org/details/64308/0.

Hoss, S., C. Guyer, L. Smith, G. Schuett. 2010. Multiscale influences of landscape composition and configuration on the spatial ecology of eastern diamond-backed rattlesnakes (Crotalus adamanteus). Journal of Herpetology, 44/1: 110-123.

Kamal, R., N. Sahu, J. Rahul, S. Singh. 2015. Snake Bite, venom, anti-venom production and anti-venom activity of medicinal plants: A review. International Journal of Pharmaceutical Sciences Review and Research, 30/1: 227-234.

Knight, K. 2012. Snakes hear through skull vibration. Journal of Experimental Biology, 2012/215: ii.

Means, B. 2009. Effects of rattlesnake roundups on the eastern diamondback rattlesnake (Crotalus adamanteus). Herpetological Conservation and Biology, 4/2: 132-141.

Means, B. 1999. Snake charmer. National Wildlife (World Edition), 37/2: 36.

Rokyta, D., A. Lemmon, M. Margres, K. Aronow. 2012. The venom-gland transcriptome of the eastern diamondback rattlesnake (Crotalus adamanteus). BMC Genomics, 13/312: not listed. Accessed November 05, 2017 at https://bmcgenomics.biomedcentral.com/articles/10.1186/1471-2164-13-312.

Steen, D., L. Smith, M. Conner, J. Brock, S. Hoss. 2007. Habitat use of sympatric rattlesnake species within the Gulf Coastal Plain. The Journal of Wildlife Management, 71/3: 759-764.

Waldron, J., S. Bennet, S. Weltch, M. Dorcas, J. Lanham, W. Kalinowsky. 2006. Habitat specificity and home-range size as attributes of species vulnerability to extinction: A case study using sympatric rattlesnakes. Animal Conservation, 9/4: 414-420.