Eastern Indigo Snake (Flier)
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How To Distinguish Eastern Indigo Snakes Eastern indigo snakes became federally protected as threatened under the Endangered Species Act From Other Common Species in 1978, and they are also protected as threatened by Florida and Georgia. It is illegal to harass, harm, capture, keep, or kill an eastern indigo snake without specific state and/or federal permits. Life History Eastern indigo snakes use a wide variety of habitats The historic range of the eastern ranging from very wet to very dry. They tend to stay indigo snake (shown in dark green) in a specific area known as a home range, but this extended from the southern-most tip Adult eastern indigo snakes may be area is not static and can change over time, of South Carolina west through southern confused with few other species, due Georgia, Alabama, and into eastern to the indigo’s glossy blue-black probably in response to habitat conditions and Mississippi. The current range is shown in color and large size (5–7 ft.). prey availability. Because indigo snakes are sizeable light green. The eastern indigo snake (Drymarchon predators that actively hunt for their food, they couperi) has the distinction of being the need large home ranges. Males have been shown longest snake native to the United States. to use between 50 and 800 acres, whereas females often used for shelter. The snake may share the Eastern indigos typically range from 5 to 7 occupy up to 370 acres. During the winter, home burrow with a tortoise, but most often indigos will feet long, but can reach lengths greater than range sizes are smaller, particularly in the cooler occupy an old burrow that a tortoise has deserted. 8 feet. Indigos are robust and glossy black, portions of the indigo snake’s geographic range. Other den sites include root mounds at the base of with smooth conspicuous scales. The lower trees and shrubs, piles of sticks and/or dirt, and face and chin may be black, light gray, or Indigo snakes, like all snakes, are reptiles and man-made debris piles. Indigos use dens not only red, and the coloration can extend down therefore are “cold blooded.” They are at the as protection from seasonal temperature extremes, Racers (Coluber constrictor), occur in a the body past the throat. Indigo snakes are mercy of temperature extremes in the environment but also from daily temperature fluctuations, fire, wide variety of habitats. Adults are non-venomous and generally docile; they and must protect themselves from excessive heat inclement weather, and predators just before and black or dark gray, slender, 3–5 ft. rarely become aggressive even when and cold. Although indigos are very general in the during shedding, when they are particularly long, with white or brown chins. threatened. They are long-lived, and captive types of habitats they will use, their home ranges vulnerable. individuals have survived for 25 years, but must include suitable den sites. In places where life spans in the wild are likely much shorter. indigos share their habitat with gopher tortoises Eastern indigos actively search for prey during the (Gopherus polyphemus), tortoise burrows are day and enter dens at night. They consume a wide Eastern indigos were once common from variety of foods; virtually any small vertebrate that west of the Savannah River in Georgia to is available will be grabbed and swallowed alive. southeastern Mississippi and throughout Fish, frogs and toads, other snakes (including Florida, including the Keys. Their current venomous snakes and other indigos), turtles, range is restricted to southern Georgia and birds, and small mammals are all documented The eastern hognose snake (Heterodon platirhinos), peninsular Florida, including the upper prey of the indigo snake. which also occupies pine-scrub oak habitat, may occur and lower Florida Keys, with a few isolated in a melanistic (dark) color phase. However, the eastern hognose is a short (2–3 ft.), thick-bodied snake with populations in the Florida panhandle. Because adult eastern indigo snakes are so large, an upturned snout and is easily distinguished from Populations may also persist in localized Eastern indigos are large glossy blue-black snakes that they have few natural predators. However, red- the larger, glossy blue-black indigo. areas of southern Alabama. can reach lengths of 7–8 feet as adults. tailed hawks, alligators, and larger indigos have adult, or may be speckled with blue or white flecks that To date, the Endangered Species Act has been ineffective meaningless without a commitment to proper land fade within a few months. The number of eggs that typically in protecting eastern indigos against the greatest threat: management. hatch, what young snakes do, and how well they survive the loss, fragmentation, and degradation of their habitats. in the wild are just a few of the many questions we cannot The detrimental effects of habitat destruction are obvious, What Can You Do? yet answer. as all species require suitable habitat. However, at present, You can help protect and conserve eastern indigo there are no reliable survey methods to detect the snake populations in a number of ways. Threats & Problems presence of indigo snakes on a site. The difficulty in n First, educate yourself and others about Although eastern indigo snakes were federally protected confirming their presence hinders effective legal indigos and the vital role that all snakes play in in 1978, there is general agreement among professional protection and mitigation for loss of individuals, the environment. There are many people who Eastern indigo snakes may use occupied or abandoned and amateur herpetologists that their populations have populations, and habitat. would not harm snakes if they realized what gopher tortoise burrows as den sites. continued to decline. There are many threats that important and interesting creatures snakes contribute to the loss of individuals and small populations. Habitat fragmentation is as serious a threat to the eastern really are. Irrational fear and prejudice can been documented to prey on indigo snakes. Before being protected, eastern indigo snakes were com- indigo snake as is outright habitat destruction. Because often be cured by one positive experience. Domestic cats and dogs also have been known to monly kept as pets, effectively removing these individuals indigos move over large areas, they are often forced to n Be an informed voter. Support officials at all kill indigo snakes. Although not confirmed, other from the breeding population. The practice of “gassing” cross roads while searching for food and mates. One levels of government who recognize the value large raptors, bears, pigs, bobcats, and coyotes gopher tortoise burrows (pouring gasoline into burrows study documented vehicular mortality as the single of our natural resources. The most important may prey on indigo snakes. Hatchling and juvenile to drive out the occupants) as part of rattlesnake roundups greatest cause of mortality for indigo snakes. Habitat factor in saving the eastern indigo snake from indigos, as well as eggs, could easily be eaten by undoubtedly took a toll fragmentation also increases the chances that an indigo extinction is the conservation and proper many animals, and mortality is probably much on indigos, as well as will come into contact with a person, a situation where management of large tracts of habitat. It will higher for these life stages than for adults. many other species of the snake often loses. not matter how many individual snakes we save wildlife. This practice is if there is no habitat for healthy, reproducing Very little is known about eastern indigo snake now illegal in Florida and Habitat degradation is an indirect, yet serious, threat to populations to thrive. Strong laws to protect reproduction in the wild and what information is Georgia, but the laws are indigo populations. Habitat may degrade over time for a wildlife and habitats (and enforcement of those available comes from captive populations. Mating difficult to enforce. number of reasons, including lack of fire or changes in laws) are not necessarily incompatible with re- occurs from winter to early water levels or water quality. These and other extrinsic sponsible development and a robust economy. spring and males and Another source of factors can influence the abundance of prey, availability It is possible, and preferable, to have both. females are often found mortality to indigos and of suitable den sites, or access to mates. Setting aside This document was a joint production of the U.S. Fish together during these many other species of habitat for indigos and other wildlife species is and Wildlife Service, the Georgia Department of Natural months. Although captive snakes is intentional Resources Nongame-Endangered Wildlife Program, indigos can reproduce every killing by humans. Although it is illegal, many and the Savannah River Ecology Laboratory year, this information is only indigos are harassed or killed simply because (www.uga.edu/srel), in support of Partners in now being collected for wild they are snakes and some people are afraid of Amphibian and Reptile Conservation (PARC; www.parcplace.org). Text by Rebecca snakes. Between five and ten all snakes. Harming an indigo snake is a federal photo by Stan Moore B. Smith, Dynamac Corporation. large, oval, rough-textured offense that violates the Endangered Species Photos by David E. Scott, SREL, except eggs are laid in spring, but Act; conviction is punishable by substantial fines as indicated. Layout and design by the location and substrate for and/or incarceration. Education of the general Laura L. Janecek, SREL. nest sites are unknown. The public regarding the indigo’s protected status young are 16-24 inches long Habitats of the eastern indigo snake and the role of snakes as important at hatching. They may have range from dry pine-scrub oak components of our ecosystem would help stop One study documented vehicular mortality as the single greatest the same coloration as an (bottom) to mangrove swamps (top).