The Eastern indigo snake is the longest non-venomous snake in North America. Adults are typically between 5 and 7 feet long, but can reach a length of over 8 feet. They are an iridescent, glossy, blue-black and may have a red or cream patch on their throat or the side of their head. Hatchlings are similar to the adults, but may have white bands around their body. Eastern indigos are sometimes confused with black racers. Black racers, however, are rarely longer than 4 feet, are thinner, and are a dull black with white or brown throats.
Eastern indigo snakes are protected by The United States Fish and Wildlife Service (FWS) and the Florida Fish and Wildlife Conservation Commission (FWC) under the Endangered Species Act and Chapter 39, Florida Administrative Code, respectively. The Eastern indigo snake has been listed as Threatened since 1971 by the state of Florida and since 1978 by the FWS. This protection makes it illegal to possess, harm, or harass Eastern indigo snakes.
Historically, the range of the Eastern indigo snake included the coastal plain of the southeastern United States, from South Carolina through Florida. Currently, most Eastern indigo snakes are found in Florida and southern Georgia. Recently, it has been reintroduced in several locations in Alabama and Mississippi.
The Eastern indigo snake can be found in a variety of upland and wetland vegetation communities. In Charlotte County, they can be found in pine flatwoods, oak hammocks, scrub, and along fresh water marshes and riverine systems. In extreme southern Florida, Eastern indigos are found in hardwood hammocks, fresh water marshes, and mangrove swamps. In north and central Florida, indigo snakes are found primarily in dry vegetation communities including scrub and pine flatwoods, where they utilize gopher tortoise burrows. Although gopher tortoise burrows are used throughout their range, they are especially important in northern Florida where they are used by the indigo snake to keep warm during the winter, and to keep cool and prevent dehydration in the summer. In wetter areas, and those that lack gopher tortoise burrows, indigo snakes use armadillo holes, hollow logs, or other holes for dens. Home range size is highly variable; the home range of adult males in south Florida averages 180 acres and can be up to 470 acres, while adult females usually have home ranges of 45 acres and up to 120 acres. Home ranges generally are largest during the summer and shrink in size during the winter, as their activity level decreases.
Eastern indigo snakes commonly eat frogs, toads, salamanders, birds, small mammals and other snakes. Juveniles most commonly eat invertebrates. Indigo snakes generally hunt along the ground during the day. Wetlands and gopher tortoise burrows are important hunting grounds.
Indigo snakes do not constrict or use poison to kill their prey. Instead, they immobilize their prey by pressing it against the ground and swallowing it alive.
The Eastern indigo snake requires large amounts of undeveloped land. Currently, the largest threat to the Eastern indigo snake is loss of habitat due to construction of buildings and roads. As development increases, habitats become fragmented and can lead to the isolation of populations or leave individuals without mates. Vehicles hit and kill Eastern indigo snakes as they cross roads within their home ranges or as they warm themselves on the pavement. Indigo snakes were once heavily collected for the pet trade because of their beauty and docile temperament in captivity. It is now illegal to keep indigo snakes without a permit.