SCCF Pine Island Sound Eastern Indigo Snake Project
The eastern indigo snake (Drymarchon couperi) is a large, docile, mostly black nonvenomous snake native to the southeastern United States. Indigo snakes have a reddish neck and chin and are often confused with the southern black racer snake (C. constrictor; average size 2.5 4 ft). Males average 6 8′ in length and females average 5 – 6′ in length. Indigo snakes eat a variety of prey including rodents, birds, frogs, fish, but their main prey item is other snakes (including rattlesnakes). They are called indigo snakes because their black scales reflect blue or purple when the sunlight is upon them at the right angle. This species is listed as threatened by the state of Florida (1973) and the U.S. Fish & Wildlife Service (1978). It is totally protected from take, collection, commercialization, and harassment throughout its range. SCCF has partnered with the Orianne Society, a non-profit organization dedicated to the survival of eastern indigo snakes, to help assess the population and find ways to ensure the survival of the remaining populations in Pine Island Sound. The SCCF Pine Island Sound Eastern Indigo Snake Project (SPISEIP) is actively capturing and marking indigo snakes on the islands and has processed four on Pine Island to date.
The indigo snakes found in Pine Island Sound are the last remaining island populations known from the west coast of Florida. The only remaining island population on the east coast is Merritt Island. It is no surprise that indigo snakes are in decline in Pine Island Sound. They have been extirpated from Sanibel since 1999 and most likely from Captiva since the late 1980’s. They still exist in small numbers on islands without a bridge connecting them to the mainland, such as North Captiva and Cayo Costa. There are still an unknown number of indigo snakes on Pine Island and SPISEISP is trying to inventory these extremely rare barrier island residents to find out the rate of decline and how to slow it down.
Indigo snakes have very large home ranges (up to several kilometers for males) and their biggest threat is busy roads. The loss of indigo snakes on Sanibel and Captiva is mostly due to roadkills. Since these snakes are on islands, they use a lot of the available real estate and are crossing roads often. Indigo snake sightings were noticeably decreasing in the early 1980’s due to higher traffic on Sanibel and Captiva. Major roads like Periwinkle Way and Sanibel-Captiva Road run through the middle of the island bisecting major tracts of land that contained indigo snake habitat. I fear that Pine Island resembles Sanibel of the 1980’s and Stringfellow Rd, on Pine Island is causing the same effect. These snakes are frequently seen in residential neighborhoods and fruit groves because these areas have a high abundance of prey items. They are extremely docile and pose no threat to people.
I (Chris Lechowicz) and my team are actively marking and measuring indigo snakes throughout Pine Island Sound. The most important way to save these animals is public awareness. We are asking for help from the residents of Pine Island to report sightings of these precious residents, even deceased animals. If you see an indigo snake, please take a picture, record the date and location, and send them to indigo@sccf.org or call 239-472-3984. Remember, these are state and federally protected species and you must have a permit to handle them. SCCF has federal permits to capture, collect data and genetic samples, and mark these rare animals for future identification. With the help of Pine Island residents, perhaps the future of indigo snakes on your island will not mirror that of other islands in Pine Island Sound.