By Fredrick Albury

Misunderstood by many, the Eastern Indigo Snake, Drymarchon couperi, is one of the crowning jewels of native United States snakes. Many herpetologists have purchased and imported snakes from around the world while virtually ignoring this stunning and impressive serpent. Their beautiful color and stunning iridescence, as well as their alert mannerisms and interaction with their keepers have made them a very sought-after snake in the last several years. They are uncommon in the hobby, but thanks to the efforts of a handful of dedicated breeders, captive bred neonates are occasionally available. This snake has a reputation for being difficult to breed, with females becoming egg-bound or regularly laying slugs; sometimes they produce nothing at all. Compared to many other colubrids available to the public, there are relatively few successful breeders of Indigos offering neonates for sale.

Eastern Indigos are only found in Florida, Georgia, Alabama, and Mississippi. They are listed as a Federally protected species, listed as a Threatened animal, and the proper Federal permits must accompany all interstate sales. Indigos hail from the same habitat as the white-tailed mule deer, the Gopher Tortoise, Eastern Diamondback Rattlesnake, and pileated woodpecker. This habitat is increasingly threatened by development, as the human population in the South continues to expand.

In the wild, Eastern Indigos occupy the niche of opportunistic predator, consuming anything of suitable size that they may come across. Fledgling birds, rats, mice, snakes, salamanders, frogs, toads, fish, and baby alligators are all part of their natural diet.

Indigos capture these prey items without the use of constriction; they simply grab and swallow, occasionally thrashing the prey item to subdue it. The Eastern Indigo Snake is the largest snake in the United States and can grow to nine feet in length. I have seen and have kept one that was actually in excess of nine feet, but that is a rarity.

Caging

Indigo Snakes are active snakes, and male Easterns typically have a large home range. They spend a lot of time hiding in Gopher Tortoise burrows. Taking their natural history into consideration can help us to maintain them successfully. I recommend a cage of at least 48 inches in length, but ideally a cage that is 72 inches long and 24 inches wide would be better. The larger cage allows them to move around more freely and prevents them from having to sit in their own waste products. People crowd them in cages that are to small, and this contributes to their reputation as messy snakes. I recommend cages that are composed of plastic; various brands of molded cages seem to work very well for this particular colubrid. Melamine cages also work well, but they have to be sealed well to prevent the melamine from absorbing water or feces. Melamine also tends to retain the smell of the feces. Wood is a bad choice, and glass aquaria are a backbreaking task for the keeper to clean and are not recommended. The substrate can be aspen bedding, recycled newspaper pulp, newspaper. I prefer newspaper; Eastern Indigos tend to ingest substrate in the act of feeding. Newspaper is cheap, easy to dispose of, and convenient. The inside of the cage can be cleaned with a solution anti-bacterial soap and water, followed by disinfecting the surface. I have had good results with this regimen. Rinsing the cage thoroughly with water and air-drying is a must after disinfecting. Water bowls must be scrubbed out and disinfected with bleach weekly. I use a 20 percent solution of bleach on mine and allow the bowl to soak for 30 minutes. Keeping the cage clean is key with these snakes-the most important aspect of their care. A suitably sized hide box makes the snake more comfortable and more confident. Cat litter pans and plastic sweater boxes work well. Naturalistic vivarium design is not recommended with these snakes, as constant cleanliness is necessary.

Proper temperature gradients in the cage are as important for Indigos as for any other herp. The warm side of the cage should not exceed 82°F, with the rest of the cage kept at HOF Excessive temperatures (83 to 90°F) trigger a host of events, namely regurgitation and quickening the snake's already rapid metabolism. This translates to more cage cleaning.

Feeding

In the wild, Eastern Indigos eat a wide variety of food items, including fish, wild rodents, birds, and other reptiles (including other Indigos). In captivity they do well on pre-killed rodents of an appropriate size. The mouth of an Indigo Snake is not suited for large meals, and adults fare better on a diet of small rats and adult mice than on a diet of medium to large rats. I supplement my snake's diet with thawed/frozen smelt, as per a suggestion by Indigo keeper Greg Maxwell. Neonate Eastern Indigos often have to be started out on goldfish or small snakes and then later switched to pinky mice. Live prey is not recommended, as the snakes get too excited in their attempts to thrash the prey and can injure themselves in the process. I feed adults in 7 to 10 day cycles all that they can consume at one time. I have known breeders that fed them every three to four days and that seemed to work for them, but the amount of cage cleaning involved was excessive. Fresh water must be present at all times. Feeding is best accomplished with hemostats or tongs, as the Indigo goes into frenzy at feeding time and with no malice other than it's hunger, will literally bite the hand that feeds it. I recommend feeding the snakes in a separate container from the one they reside in.

Breeding Information

Eastern Indigos are fall/winter breeders, whose reproductive cycle corresponds with the shortened day length and cooler temperatures of the fall and winter seasons. Brumation is not necessary for these snakes, and I know of instances where adult Indigos have died during brumation. Daytime cage temps of 79 to 82°E; with a drop to 65 degrees overnight are fine. Nighttime cage temperatures lower than 65°F are not recommended. Breeding season starts in October and continues through December. While your typical colubrids are having their siesta and brumating, Indigos are mating up a storm. Breeding Indigos is not a science. Most other colubrids and quite a few boids already have hobbyist derived formulas for reproducing them. Indigos are unique in that many breeders have experienced utter failure, even though they set up conditions perfectly. My understanding of this is that there are many ways to achieve success with the breeding of this snake, and something is always being learned.

That said, Indigos should be at least four years old before attempting reproduction. I have seen breeding sooner, but I have also seen the same females get egg-bound. None of the snakes of at least four years of age that I breed have become egg-bound. Take your time, raise them, and try to reproduce them when they get old enough and large enough. The male Eastern Indigo will climb the walls of his cage during breeding season. Introduce the male to the female's cage at this time, but keep a wary eye on them, as Indigos sometimes eat other Indigos. Usually mating commences immediately, and can last anywhere from 20 minutes to eight hours. Multiple mating is desirable. Breeding is a rough affair, and the female can be scarred up badly, so watch them closely. Pairs should be kept together in November, and separated only for feeding purposes. Females show signs of gravidity between March and April, at which time the male should be returned to his cage for the rest of the season.

Incubation

Female Indigos must be given an egg-laying box. A plastic sweater box filled with slightly dampened sphagnum moss is ideal. Cut a hole in the lid large enough to allow the snake to move easily in and out of the box. Early April to mid-May is the time when the eggs are usually laid. Now comes the fun part. Indigo eggs cannot be treated in the standard colubrid manner. The normal incubation temps of most colubrids (82 to 85 degrees) will result in dead eggs or in neonates with spinal kinks. I believe that lower incubation temperatures, within the range of 75 to 80°F, are the key to success with this species. The lower temperature means a longer incubation period, 80 to 100 days being normal. If you want to produce the young sooner at a higher temp, you may well do so, but you run the huge risk of producing deformed or dead babies. After the first egg hatches I recommend carefully cutting small slits in all the eggs to facilitate hatching. This can be done with cuticle scissors, the cuts being no wider than a half-inch in length. This practice helps to prevent full term egg death, a common occurrence with Eastern Indigo neonates.

Neonate care

Small plastic shoeboxes are the best vessel for housing neonates. I recommend using a substrate, and a small water bowl. Apply heat under about one-fourth of the box. Neonate Eastern Indigos are notoriously difficult to get to take their initial meal. Often goldfish, minnows, frozen trout, or small frogs have to be offered to elicit a feeding response. It is not uncommon for neonate Eastern Indigos to go 60 to 90 days post hatching before they consume their first meal. Through the use of scenting techniques they can be switched to small pinky mice. This whole process requires lot of patience. Remember, they are not like other colubrids.

There is so much to still be learned about these awesome serpents. I am humbled to have had the opportunity to be able to keep and even breed these snakes. As I said before, many theories abound as to why we have success or why we have failure with the captive propagation of this snake. I believe that each person that keeps them and breeds them can also add a bit of knowledge that otherwise would have been overlooked. Despite the high level of care they require and the lack of financial return they offer to those who breed them, Eastern Indigos will always remain among the most treasured snakes in my collection. With a little bit of research and a lot of commitment, I hope they become your favorite, too.