a philosophy of reptile husbandry

“The bad old days of ‘rack ’em high, breed ’em fast’ are over. Super sterile enclosures that do nothing for mental or physical enrichment are fading away quickly as we start to walk headlong into an exciting era of high education and thoughtful, accurate supply. We must, as modern keepers, grasp the fact that it is far better to care for a small number of animals and to provide them with the ability to behave naturally than it is to overreach ourselves with huge collections and fall into the trap of providing our collections with ‘minimum standards’. The watchwords must be ‘ethical care equates to effective care’.” — John Courteney-Smith, The Sun: Its Use & Replication within Reptile Keeping

In recent years, since returning to the hobby of snake-keeping in general and Indigo Snakes in particular, I have learned a great deal more than we knew when I was first in the hobby and the industry decades ago. The herptile hobby has exploded with increasing popularity, accompanied by massive quantities of freshly minted information and scientific research, along with new technology and equipment for keeping reptiles that wasn’t available a decade ago, and in many cases, even five years ago. From heating, lighting and enclosures to breeding, behavior and enrichment, we not only know more than we have ever known before, but we are literally continuing to discover and learn more every day. While it is my intention to provide husbandry information and guidance that reflects the latest trends and data, I want to begin by acknowledging that there is a new school of thought afoot in the reptile keeping world, that departs from many of the old ways. It is not merely that “folklore husbandry” is being replaced by science-based guidance, but there is also a growing conflict between old school and new school assumptions and approaches, that might be most cogently summarized as the difference between two different sets of goals and guiding principles, namely the difference between:

SURVIVE versus THRIVE

• Old School: SURVIVE

Consistent survival of animals and meeting fundamental physical health requirements is sufficient for quality captive care and maintenance over the long term. Animals can survive and even breed in small enclosures, rack systems, unnatural conditions, limited monoculture diets, minimum and often only ambient heating, and no UVB lighting.

• New School: THRIVE

Survival and fundamental health are insufficient standards for captive care of reptiles. Reptiles should be kept in the very best conditions we are capable of providing, including the larger the enclosures the better, naturalistic settings that attempt to imitate native habitat and encourage natural behavior (tunneling, climbing, etc.), added enrichment, the best diet, basking and belly heat, temperature and heating gradients, appropriate (often multiple) hides, UVB lighting, and approximating a natural daily and possibly seasonal light cycle. This simple set of definitions is not intended as an attack on the old school, nor an attempt to paint commercial breeders with a single broad brush. I try to take a broad-minded, fair-minded approach in the materials and guidance that follows. But before I do, the most important conclusion I have come to in considering these issues is that the reptile hobby needs to reframe its approach, attitude, and vision—indeed, its fundamental culture. I believe that the culture of reptile keeping should adopt as its primary operative principle:

CONNECTION – NOT COLLECTION

I understand the desire and appeal of collecting reptiles. When I moved into my first apartment, two weeks after I turned 19, I had one snake – a Florida Chain King (Lampropeltis getula floridana, aka brooksi at the time), which I had purchased (decidedly against my mother’s wishes) when I was fifteen. A year after moving out I had 28 snakes, six tarantulas, and more on the way. I kept Paradise snakes, four types of Tree Boas, a breeding pair of common Boa Constrictors, a large Reticulated Python (who would reach about 12 feet), and eventually a breeding pair of Eastern Indigo Snakes. I understand the temptation, the desire, and the appeal of collecting. With every addition to the collection, we can’t help but think about what we might add next. For myself, I love all the Drymarchon species, especially Eastern Indigo Snakes and Blacktail and Yellowtail Cribos; Old World rat snakes including Tiger Rat Snakes and Blue Beauty Snakes; some of the mild rear-fanged species like Mangrove Snakes; and Emerald Tree Boas. I admire these species longingly whenever I see them. Snakes are infinite in their variability, beauty, and cause for fascination. I get it. But with our dramatically increased knowledge about what it takes to create conditions that allow our reptiles to not merely survive but rather to thrive, I believe hobbyists need to have a serious reckoning with themselves about the limits of their resources, including space, money, time, and effort. And about whether their priorities lie first with themselves and their desires, or with their animals, for whom they assume responsibility once they put down their dollars and bring another purchase home. The more animals you keep, the more you become a collector rather than a connector. If you have one, two, three, or four animals, you stand a strong chance of working toward keeping them in the very best conditions, conditions that would be the envy of many zoo reptile houses. And the more you create these conditions, the more your animals thrive, your more pleasure you will both get from the experience, because the best conditions lead to animals that are more interesting to watch and interact with, that exhibit more varied and natural behaviors. How much better is it to be able to thoroughly connect with a select few animals than to have a collection of animals in racks of tubs or even small glass enclosures but for which you are unable to provide the very best care and conditions, much less have time to focus and appreciate each and every one of them? I do not consider myself an animal rights radical. I believe in the pleasures of keeping reptiles as a personal hobby; I believe in the existence of zoos as educational and scientific institutions (but not merely as places of entertainment—please boycott Sea World until the day comes we can legally shut them all down). But I have come to believe that the old school of reptile husbandry reflects assumptions that are no longer applicable and, in the near future, will come to be generally regarded as unacceptable. I propose that we all stop thinking about collecting, and focus on connecting with our animals. And if we do this, the hobby will grow healthier, and its reputation will improve, as will the lives of every animal in our care, and every keeper caring for them. I am not a person trying to end or restrict the reptile hobby. I want the hobby to thrive, not just survive—just like our animals. So, I ask you please, to consider a new way of thinking and approaching our shared passion. Think:

CONNECTION – NOT COLLECTION

I am not a big fan of so-called “care sheets.” I suppose they have their place, but they should be labeled along the lines of “A Brief Introduction to Care Basics.” The current state of affairs renders many care sheets hazardous, because keepers—especially prospective future hobbyist and newbies—are often inclined to mistake the care sheet for the whole story rather than see it as a summary outline. Care sheets are at best a place to start, but should never represent where you end in terms of learning how to care for captive herptiles.

Hence this page should in no way be considered any sort of definitive care sheet, but rather, despite its length, an abbreviated introduction to the care and requirements of Eastern Indigo Snakes.

What’s more, I often find myself thinking of the words of John Michels of Black Pearl Reptiles, who has said to me (on more than one occasion), in essence: “I don’t believe there is one correct way of doing things. I can tell you what has worked for me. If something different works for you, that’s great. And I’m always willing to learn.”

While I imagine I will update and tweak this page many times in the years to come, I hope to continue to remind myself of John’s words. It’s true that in science we can establish testable truths, and I am someone who is very much about the scientific method, replicable results, and data—wherever and whenever possible. By the same token, there are times when we don’t yet have the data—let’s face it, herpetoculture science is young and in many areas still slender—and so we have to combine the available science with expertise, experience, and our own best reasoning abilities, and sometimes come to a best guess decision—at least until something better or more certain comes along.

Ultimately, most humans are often not very good at any of those last few items—we evolved with an unbearably weighty set of hardwired cognitive biases as social hominids hunting large mammals on the African plains—and these are difficult thinking traps to escape. That’s why science invented double-blind protocols—to help save ourselves from our own lousy observational abilities and poor critical thinking tools.

So I’m good with saying, and thinking, something like: “Well, I’ve thought about it, and ultimately this is the choice I’ve made, but I acknowledge that I’m guessing. I don’t really know how a snake thinks or feels or experiences the world, but I’m trying to take my best guess based on what little we know, so I can do the best job of taking care of it while enjoying the privilege of its company. I am willing to err on the side of what is best for the animal.”

I’m good with that. I’m not good with someone who, while fundamentally no different from me—who is taking their best guess, no matter how well intended—and is so absolutely certain that they have a personal handle on the One True Way, that they are willing to declare me and anyone else wrong, evil, or worse, for having come to a different conclusion.

Of course, if you’ve visited a herptile forum once, you’ve already met that person. But in the words of John Michels: “I’m always willing to learn.” I hope you are too.

There’s nothing wrong with that, and indeed it is at times a necessity, but—and this is a very important “but”—we need to always be self-skeptical, and simultaneously open to considering new ideas, and willing to change our minds. To pretend that we know the single correct answer with absolute certainty leads us to drown out other voices, to chase away legitimately interested parties from what should be a “big tent” of hobbyists, and fuels a stubborn sense of certainty that is often unsupportable by logic or currently available facts. It’s one thing to make an informed, reasonable guess. It is quite another to fail to distinguish between a sound guess and testable facts.

Hence you are welcome to the information provided on this page and website, the results of my own long experience and research, along with the work and thinking of countless other individuals. You are welcome to put it to use—and I hope you do!—and you are welcome to disagree with it. But it is not presented as the One True Way, and while I will try to indicate where certain conclusions of Indigo care are generally agreed upon, I will also try to be fair and present at least some aspects of multiple points of view where they exist and where there are legitimate disagreements and controversies. And while I don’t wish to drown this page in scientific papers—you can find those kinds of more extensive references on the Resources page—I will try to provide select research data in support of the conclusions and opinions presented here on the Husbandry page.

Finally, I am a professional writer (the author of six books), not a YouTuber. I tire easily of the endless river of what passes as “content” in the form of video, finding much of it boring, uninformative, at times downright silly and often just plain wrong. I recognize that reptile YouTubers will continue to garner far more interest than this website. There’s nothing I can do about that, but I will be clear: the original content and other resources of this website are primarily written. I write what I would want to find and read in my own search for advice and expertise. These husbandry pages essentially amount to an online book: Impeccable Indigos: “The Care and Maintenance of Drymarchon Couperi in Captivity”, by Jamy Ian Swiss. Like any good book, you won’t read it all in one sitting. But I hope readers and researchers explore the material, read and consider it, and above all use it—but if you’re looking for videos of teenaged “experts” frantically avoiding getting bitten, or actually being bitten, or otherwise prattling on endlessly on camera because they can’t or won’t write a sentence and their fans can’t or won’t read one anyway—you’re on the wrong site. I sincerely hope you’ll stick around here for a while, thought, and try something different. Who knows—you might like it, and you might learn something. I hope you do, because above all, that’s why this site is here.

There is no other snake like the Eastern Indigo, long considered the most desirable of snake species kept as pets, despite some of the challenges of maintaining them. When I was in the reptile and aquarium pet trade in the 1970s, despite handling hundreds of species of snakes, thousands of specimens, and keeping dozens of animals at home as well as breeding multiple species, I fell in love with Eastern Indigos and they became, and have always remained, my personal favorite. When I returned to the hobby after many decades’ absence, I no longer had any desire or intention to collect multiple species or large quantities. I simply want to raise Eastern Indigo Snakes. And among a select coterie of like-minded individuals, we will all quickly tell you of our shared obsession and love affair with this singularly extraordinary species.

The Eastern Indigo Snake (Drymarchon couperi) is North America’s largest native snake*, with the record being held by a specimen that was reputedly recorded as more than nine feet in length. Far more commonly, males typically reach to between seven and eight feet, and females (unlike many other snake species) typically end up about a foot shorter on average.

Indigo Snakes are essentially black in color, with variable red-to-rust or brown coloration on the lower side of the head and forward-most body. The black upper body, notably when illuminated in natural sunlight, shines with a scintillating blue-black iridescence that is the source of their common name, “Indigo.” Eastern Indigos also routinely appear in a second color phase, which while considered “black,” typically leaves some off-white coloration beneath the chin, however there is no red present. This is not a separate species or subspecies, it is merely a genetic variation, and any combination of parents that are red-to-red, black-to-black, or red-to-black, will frequently produce a mix of each variant among the young.

Indigo Snakes have scales that are smooth and large, notably on the head (not unlike King Cobras, with which Indigos share many traits, but Indigos are not venomous), and the Eastern Indigo is widely considered to be among the most uniquely beautiful snake species in North America, and indeed the world.

While their original range spread through northern and southern Florida into the Florida panhandle including Georgia and Alabama, their native range has been drastically curtailed over the past half century, due to over-collection for the pet industry (at one time) and primarily continual reduction of their natural habitat due to commercial development. In 1978, Eastern Indigos were placed on the Federal Endangered Species List and classified as a “Threatened” species, a status that they continue to maintain today. (On the Resources page you will find interesting information about efforts to restore the species to portions of its original range by introducing captive bred Indigo Snakes to the wild.)

Indigos are members of the Drymarchon genus, which are in turn part of the family of Colubrids, which are generally speaking relatively later evolved group of snakes than boas and pythons, and are invariably more slender bodied. While many colubrids are constrictors, and some are venomous, Drymarchon are distinctive in that they are neither. Rather, Drymarchon kill and consume their prey purely by overpowering them. Drymarchon have notably stronger jaws than most other snake species, and they will seize live prey and subdue it by any means necessary, perhaps a combination of slamming it against nearby rocks or similar, crushing with their jaws, and generally bulldozing the prey with extremely powerful and aggressive striking behavior that tends to grab the prey animal and continue to barrel forward until the prey strikes an obstacle, or the prey is otherwise overpowered and rapidly swallowed, sometimes while still partially alive.

Indigos are active diurnal animals that can cover distances of as much as three miles when hunting food or looking for mates. While venomous snakes are often ambush hunters—using natural camouflage and waiting quietly and still for long periods until prey comes into reach—Indigo Snakes are active hungers with strong vision. While many other snake species are extremely specialized eaters, Drymarchon in general and Indigo Snakes in particular are relatively eclectic in their tastes, consuming everything from insects and invertebrates for neonates, to fish, amphibians, lizards, snakes, birds, and small mammals. In the wild, other snake species are a particularly common choice of prey, including large rattlesnakes, one of the many reasons Indigo Snakes are valued by farmers and others who live in native Indigo territory.

Unlike most other snakes that consume whole animal prey, Indigos do not have flexible jaws and so are unable to swallow the large meals often taken by boas, pythons, vipers and many other colubrid species. Hence it is thought that for Drymarchon species, preying on snakes is an advantage because a larger meal can be consumed—a long slender prey animal being ingested by a long slender predator. As part and parcel of these behaviors and characteristics, Indigos and Drymarchon in general tend to have high metabolisms, needing to frequently eat relatively small meals rather than the infrequent large meals of species that can go weeks if not months between feedings.

This content is not intended as a thorough primer, and more information can be found on the Resources page under “More About Indigos.” What is most important perhaps about Indigo Snakes as far as hobbyists reptile keepers are concerned is my claim on this site that the Indigo is North America’s most charismatic snake—and actually I would say that it is likely the most charismatic snake in the world (perhaps along with the King Cobra).

This is because Indigos are not only beautiful, muscular, and magnificently impressive when at adult size, but they are generally agreed to be among the most intelligent of all snakes quickly taking in new information about new experiences, learning to recognize their keepers, and being generally curious and investigative about their surroundings. (It’s fair to say that King Cobras are similarly intelligent, and possibly Reticulated Pythons as well. However, such beliefs about relative intelligence are essentially anecdotal, even when based on extensive firsthand experience by keepers; that said, keepers tend to be biased toward their own favorite species.) What’s more, Eastern Indigo temperaments are unmatched, invariably growing into confident, commanding animals that are uniformly disinclined to bite. While Indigos, and more so other Drymarchon species, can be a bit of a challenge to handle because of their energy, strength, and curiosity, biting is not what one risks with an Indigo, even when in the hands of an inexperienced handler. While it is difficult to explain with certainty this consistent nature of this fantastically docile, thinking wild animal, one suspects that because adult Indigos are apex predators at the peak of their local food chains—their Latin name translates roughly to “lord of the forest”—their innate confidence prevents them from become defensive, whereas animals with more natural enemies can behave defensively, prone to strike or bite. Interestingly, King Cobras share many of these characteristics of the Eastern Indigo, including their strong vision and visual connection with the world, their thinking abilities, the fact that they are apex predators, snake-eaters, and even their ability to recognize and peacefully interact with their keepers.

[*Non-native invasive species, notably the Burmese Python in Florida, can exceed this size.]

Let’s begin with a clear statement: Indigo Snakes in particular, and Drymarchon species in general, are not beginner snakes. If you are just starting out on your snake-keeping journey, you should choose an easier, less demanding species, with which you can learn all the complexities of enclosures, heating, lighting, feeding, cleaning, and handling. For me, my preference for first-time snake keepers are corn snakes, of which there are countless varieties, and entry level prices are quite accessible, as there is no need to start off with the rarest of morphs. Other good entry-level species include some species of king snakes (Florida Chain Kings, as one good example, or perhaps California Kings). Rosy Boas are also excellent beginner pets. All of these species are hardy, generally easy to feed, and can be started in 24” or 30” enclosures and eventually moved to 48” enclosures (or optionally larger) as forever homes.

Ball Pythons are often touted as beginner snakes but I consider them borderline at best for this category, as they are more demanding in their living conditions (particularly requiring humidity), eventually require larger enclosures of at least 60” in length, and tend to go off feeding intermittently and unpredictably.

All of these species are far easier to keep than Indigos and other Drymarchon, as maintenance, cleaning and feeding are all far less frequent for rat snakes, king snakes, pythons and boas. All these species are also now commonly bred in captivity, and there is plenty of selection and ready availability. (One important note: Ironically and unfortunately, wild caught specimens are typically less expensive than captive bred animals, but with few exceptions, it is generally unethical to be taking animals from the wild today, given the ready availability of captive bred animals that do not impact wild populations, and ethical wild collection is the exception rather than the rule. There is justification for professional breeders trying to diversity their genetic lines, and a handful of dealers who have their own overseas facilities and stand behind the ethical taking of wild specimens, such as DM Exotics.)

But let’s get back to beginning your snake-keeping journey. Find out where the best specialty reptile shops are in your area, and if necessary be willing to travel a few extra miles, rather than buying your snake and setup from a national chain store (often abbreviated in hobby circles as BBPS, for Big Box Pet Shops). Support the businesses that will support you and your pursuit of the hobby; the reptile shop will have better information and a better selection of the right enclosures and maintenance tools and accessories that your animal requires. Also, watch for annual reptile shows, like the Reptile Super Show, that might come your way, and where you will find plenty of breeders and suppliers to talk, while being presented with a wealth of possibilities. But please—do not make an impulse livestock purchase! Ask questions, collect information, take notes, then go home and think about it all before you make a reasoned, dispassionate decision that will be best for both you and for your animal. Burmese Pythons, for example, are beautiful and generally very tame, but few people are prepared to keep an animal that can easily reach ten to twelve feet in length or more and requires an enclosure of a similar length or larger. And note that any of the snakes recommended here can live twenty years in captivity, with Ball Pythons reaching thirty years. This is not a casual commitment!

Indigo Snakes and other Drymarchon species are better suited to keepers with at least intermediate experience, with at least one but preferably perhaps with several specimens and species over a period of time of at least one or two years, in my personal opinion. There are multiple reasons for this. Indigos eventually turn into big, strong snakes, with females reaching six feet or more and males readily growing to between seven and eight feet. While they are absolutely not prone to biting, nevertheless they are more challenging to handle than corn snakes and ball pythons that tend to be very calm and not very quick moving (baby colubrids excepted), because Indigos are very aware of their surroundings, endlessly curious and frequently on the move. (This is even more true with other Indigo and Cribo species!) It takes some experience to be able to get a big Indigo to settle into your hands or arms and be still, without trying to forcibly restrain the animal with your hands, which you should never do (and which, with some of the other Indigo and Cribo species, can possibly lead to a frustration bite).

The one way you are most likely to get bitten by an Indigo or Cribo, and badly at that, is because all Drymarchon tend to develop extremely strong feeding responses as they mature. This is a risk with almost any snake, and keepers must learn how to detect what reaction is being triggered, and how to best communicate with the snake what is happening in the moments when an enclosure is first opened. Indigo Snakes don’t bite with the intent of aggression, but you can suffer a significant bite if the animal’s food response is unintentionally triggered and the snake misjudges the situation.

Further, Indigos and other Drymarchon species have much higher metabolisms than other colubrids, boas and pythons, with very young snakes feeding on small meals as often as every other day, juveniles every three to four days, young adults every four to five days, and full adults perhaps weekly. All that food is expensive and the costs add up, particularly when providing a varied diet of pricier foods like quail and Reptilinks. And all those feedings, combined with high metabolisms, means that Indigos and Drymarchon defecate far more frequently than other snakes. What’s more, many experienced snake keepers feel that Drymarchon feces are nastier and smellier (and unarguably less solid) than that of other types of snakes, characteristics which increase with the size of the animal and its meals; moreover, some individuals are in the habit of smearing the results widely around the enclosure and its side walls and glass fronts (albeit this is far less common with adults).

Indigos definitely do not like spending extended time with feces smelling up the enclosure and so enclosures must be cleaned continuously. Indigos also require a constant source of clean water, which must be changed regularly, and certainly any time a snake defecates in it, which some individual specimens are prone to do. And Indigos have very specific heating requirements which are the opposite of most other commonly kept captives, in that they do poorly at temperatures significantly above 83 degrees, and extended exposure to temperatures greater than 85 degrees can potentially result in fatalities.

To be clear, Indigos certainly experience these and higher temperatures in the wild, however they have the opportunity to thermoregulate. In captivity, where many enclosures may not vary in temperature at all, temperatures in the high 80s are dangerous for D. couperi. On the other hand, provided that you have significant temperature gradients in your enclosures — even within my 48” PVC unit I have managed to successfully establish multiple temperature gradients that vary from four to seven degrees from one portion of the unit to another. In this case, I can safely provide a basking surface that hits 90s as a benefit rather than a hazard to my animals.

It is widely claimed that Indigos can rapidly dehydrate without readily available water, which can potentially cause irreversible kidney damage. While the truth is that Indigos will at times deliberately go days without drinking, especially when hiding out during ecdysis, nevertheless fresh water should always be available in order to avoid risk, because it is true that many Indigos will simply not drink once the water is soiled, and occasional specimens may even decline water that is stale, hence it’s wise to change water perhaps twice a week to be on the safe side, and always immediately if soiled. (Also if an enclosure overheats due to heating malfunctions, a large water dish has saved many a snake as emergency refuge.)

Large size and active metabolisms also means that Indigos are constantly growing, and will begin to require sizable enclosure by the time they reach five feet, and permanent enclosures for full adults should be in the range of six to eight feet in length. Variety of stimulation and enclosure contents is yet another factor that will make for healthier Indigos over time in captivity. We are learning more and more about the value of enrichment for all captive animals throughout the evolutionary tree, and enrichment is now a prescribed element in the Association of Zoos and Aquariums specifications for more and more species, specifically including Indigo Snakes.

Thus while I am not trying to discourage you from pursuing the dream of living with an Indigo Snake, it is imperative that you plan ahead and are prepared to fully meet its requirements, more details of which are provided in the sections that follow. But above all, it is highly recommended that you work out your beginning snake experiences on hardier, less demanding species. My first snake was a Florida Chain King, and my youngest son’s first snake is a beautiful Albino Corn Snake that the whole family enjoys watching, handling and caring for. (You can find photos of him elsewhere on the site.)

But okay – let’s say that you’ve got some successful snake keeping experience under your belt, and you’ve considered all the requirements and preparations necessary to bring an Indigo Snake into your home and successfully care for it. Now what?

Unlike the aforementioned corn snakes, ball pythons, kingsnakes and other abundant and widely available captive bred snake species, Drymarchon are far less commonplace, and hence, far more expensive than many or most other snakes, save particularly rare morph varieties that fall into the Latest Big Thing category. Drymarchon are scarcer because there are far fewer breeders, and there are far fewer breeders because entry costs are high, and breeding is far from surefire or automatic—Drymarchon can be difficult to successfully breed and incubate. What’s more, some percentage of hatchlings will invariably be difficult to feed, and require a great deal of care and attention before being stabilized on readily available feeders—typically pinky mice to start, but many hatchlings must first be fed with whatever their stubbornly innate first preference may be, be it chick parts, fish, amphibians or other possible options, and then, with scenting, gradually moved to rodents. Throughout this process the snakes must be attended to and maintained by breeders for several months at the very least. Add up all of these considerations and costs of time, effort, food and more, and Drymarchon species in general are amongst the most expensive of captive bred snake species, with Eastern Indigos being more or less at the top limit of the price range (although some Blacktail Cribos and Mexican Redtail Indigos can demand similar price tags).

Who should you buy your Indigo Snake from? Although the number of small independent home breeders is definitely on the rise, most such breeders are fairly new to the game, and are breeding one or two pairs, without much history behind them, knowledge of their snakes’ genetic origins, or experience getting neonates to feed. There are probably fewer than a dozen breeders who are consistently producing Eastern Indigos every year and have track records for having been doing so for some significant length of time, and even within this small group, best guess is that most are breeding just a few pairs annually, perhaps producing not more than three to five viable clutches a year. Only two known breeders consistently produce more than this; both have been doing so for in the vicinity of twenty years, give or take, and both are located in Southern California.

Which brings us to another key complication when it comes to obtaining an Eastern Indigo Snake. Because the Eastern Indigo is federally protected, it is not only illegal to take any specimens from the wild (it is in fact illegal to even handle a wild specimen), but while captive breeding is legally permitted, Eastern Indigo Snakes cannot be transported across state lines without possession of a Federal Interstate Commerce permit (3-200-60 Native Endangered and Threatened Species Interstate Commerce). The permit costs a $100 fee and takes several months to process, yet another barrier to obtaining or keeping Eastern Indigos. However, you can legally transfer an Eastern Indigo within a given state, so if your breeder or source resides in the same state as you, you can forego the permit process. Keep in mind that the other Indigo and Cribo species are not similarly protected by federal law (Texas Indigos are protected by state law however), and hence are much easier to obtain, so for many, you may be well advised to consider another Indigo or Cribo species rather than facing the challenges of legally obtaining an Eastern. All the Drymarchon species are beautiful, and Texas and Mexican Indigos can often be quite similar to Easterns in most characteristics.

Most responsible Indigo breeders are prepared to provide several services:

• Maintain hatchlings until they are consistently feeding and accepting rodent food (i.e. pink or fuzzy mice, preferably frozen/thawed).

• Identify the sex of the animal you are purchasing. 

• Advise and guide you through the process of obtaining the federal permit if it is an out-of-state sale, and help see you through the planning and completion. 

• Answer questions and provide substantial information and guidance in preparing for your snake and initial care and maintenance. 

• Guarantee a snake without apparent flaws, such as spinal kinks or split scales, unless such conditions have explicitly been made apparent to you. In many cases, such conditions are otherwise harmless and animals with these characteristics can not only make excellent pets, but also can be obtained for a more reasonable cost, with the expectation that they will not and should not be used as breeding stock. (And note that these flaws are not necessarily the result of inbreeding or other genetic error, but rather are often the result of variations or failures in incubation conditions, i.e. temperature, humidity, etc.)

These are the minimum expectations that a potential purchaser should expect from their source, and if there is resistance or neglect in any of these areas, you should walk away and look elsewhere.

If it has not already become implicitly clear, I will make it explicit and recommend that in general you should not buy an Indigo from a retail reseller, i.e., a pet shop. You are likely to end up knowing nothing about the animal’s lineage or origins, and this is useful information to have (and indeed significant for the small percentage who are considering breeding in the future). Perhaps a retailer or reseller has a good relationship with a quality producer, but you will have to judge if you are getting sufficient and reliable information through that chain of communication; at best this might occur with a true reptile specialty shop, but while you are unlikely to ever find any Drymarchon in a major chain store or large general pet shop, if by some strange case you were to come across such an instance, I would leave that animal right there. You want to buy Drymarchon from breeders, not pet shops, just as you would or should buy a pedigree puppy from a reputable breeder, not a retail pet shop. Beware, especially online, of sellers who are not breeders but are merely “flipping snakes” for a quick profit, and are quick to overcharge while being short on knowledge or responsibility.

It is certainly possible that you might encounter a private individual who is selling an Indigo Snake, perhaps because they are moving on from their time and attempts with the species, for example. In such cases, if you are buying firsthand directly, you stand to be able to make a reasonably informed judgment.

But in the best of all worlds, you are better off seeking out experienced breeders who have a track record with Eastern Indigos, and are selling an animal to you that they produced themselves, perhaps from parents whom they have been breeding for years, or even since a previous generation.

How do you find those breeders? It will take a bit of effort. Your best bet is to join the Facebook communities that specialize in Indigos and Drymarchon, search through the history, note the names that repeatedly come up as known breeders, and then contact those people directly. Be willing to ask a lot of questions, and also to ask for referrals. Make sure you’re dealing with someone who is serious and reliable, who has a track record in the small community of Indigo and Drymarchon fanciers, and who will stand behind their animals.

All this will not happen in a day, and serves as yet another reason Indigos are not for beginners. You need to be willing to make a commitment—indeed, many commitments. But sincere efforts will eventually be rewarded, and the reward of being able to bring an Eastern Indigo Snake into your home is a reward worth waiting for.

I began above by saying I don’t much like care sheets. The problem is that many people think a care sheet is the last word on how to care for your snake, when it fact, a care sheet should only serve, at best, as an introduction.

That said, I have gathered some of the better care sheets available into this one convenient resource. I don’t think there’s a single entry that follows here that I completely agree with. (As just one example, there is much I like about the Everything Reptiles Care Sheet, but the instruction to feed Indigo Snakes every 7 to 10 days is wrong in my opinion. Indigos can go that long between feedings, but that should be an occasional event at most.) But is useful to study such resources and compare the details. If most agree on a particular point, there’s a good chance the recommendation is correct. If several disagree, that’s an item for you to flag and investigate further (and in such cases I have provided my own recommendations elsewhere within this husbandry page).

Some of these sheet also include additional information about biology and natural history. And I should state clearly here, for lack of a better place, that most if not all of these care guidelines apply equally to all Drymarchon species of Indigos and Cribos, and that while this site explicitly celebrates Eastern Indigos, in fact the entirety of the Drymarchon genus consists of wonderful species that are all very similar in most characteristics—and they are all beautiful and wondrous animals to keep and care for.

The final two items come from the two largest and longest-standing commercial Indigo Snake breeders in the U.S., both based in Southern California.

Eastern Indigo Snake Care Manual (AZA)

Eastern Indigo Snake Care Guide

Eastern Indigo Snake Care Sheet

Eastern Indigo Care Guide

Drymarchon Care Sheet (IndigoBlack) [I like this sheet and site]

Drymarchon Care Sheet (Black Pearl)

Breeding the Eastern Indigo Snake (Robert Bruce, 2015)

“Our study indicates that D. couperi is a predator of a wide diversity of animals, including invertebrates, fish, anurans, salamanders, small crocodilians, turtles, lizards, snakes—including venomous species—birds, mammals, and the eggs of vertebrates. Although certainly not dietary specialists per se, small turtles (including young Gopher Tortoises), anurans, rodents, and snakes figure prominently in the diet of wild D. couperi.”

— Prey Records for the Eastern Indigo Snake (2010 D.J. Stevenson et al.)

***

What to Feed

In the opening section of this page (“This is Not a Care Sheet) I stated that: “I will try to indicate where certain conclusions of Indigo care are generally agreed upon, but I will also try to be fair and present at least some aspects of multiple points of view where they exist and where there are controversies.” As we get further into husbandry issues, this proviso becomes increasingly relevant, and so it begins when it comes to feeding recommendations, as we will see shortly.

The reasons to feed dead prey (either freshly killed or, more typically, frozen and thawed) as opposed to live prey have been explained at length throughout the literature of captive snake husbandry since the 1970s, and needn’t be repeated here in any depth, but I will provide a succinct summary. Suffice it to say: It is fundamentally irresponsible to feed live prey in captivity. In addition to being cruel to prey animals, it is potentially extremely dangerous to the snake, which cannot control the hunting and killing circumstances as it can in the wild because of the constrained allotted space, in which even a small mouse can inflict a serious wound, and depending on the size of the snake and the size of the prey, easily even a fatal wound, all before it’s too late for the “watchful” keeper to have the chance to intervene. If you think watching a snake kill live prey is your idea of entertainment, please (a) get off my website, and (b) get out of the reptile hobby altogether, and (c) work out your personal problems elsewhere and in healthier ways. Seek therapy.

Feeding frozen and thawed (“F/T”) prey has been the standard of snake husbandry since the 1970s, an approach that came to the wider attention of hobbyists thanks to the great American herpetologist, Carl Kauffeld [https://second.wiki/wiki/carl_f_kauffeld], Curator of Reptiles and Director of the famed Staten Island Zoo, and author of three popular books (and countless technical publications) about snakes and snake husbandry. When I discovered his Snakes: The Keeper and the Kept (1969), it changed my life and the lives of countless snake keepers in the next decade, providing standards of care which I not only adopted for my own animals but utilized as my guide in education my customers and readers over the many years I sold snakes out of a retail pet shop and wrote articles about reptile husbandry, both for industry journals and pet magazines for the public. Among Kauffeld’s many innovations are included the reliance on frozen and thawed prey; on low humidity as a default; simple but thorough maintenance; and often newspaper as a recommended substrate. While these approaches have since evolved far beyond those of Kauffeld’s era (particularly regarding humidity and also variations in more natural substrates), nevertheless at a time when enclosures were often kept overly damp and in unsanitary conditions with dirt or other random substrate materials, Kauffeld’s recommendations become the standard not only for hobbyists but also for zoos for many years.

Hence when I first kept and bred Indigo Snakes in the 1970s, I kept them on newspaper, in screen-covered aquarium tanks topped with incandescent light fixtures for heat, and fed them on a diet of mice and then, when adults, small rats, all frozen and thawed. This has been the staple captive diet of Indigos, throughout their lifetimes, along with countless other carnivorous snake species, for decades, with little if any variation.

More recently, at least for the past decade if not longer, many Indigo and Drymarchon keepers, breeders, and professional institutions have come to the conclusion that Indigos should be fed a diet of varied vertebrate prey, including birds and fish along with rodents. Specifically these food items are provided in the form of readily available feeder animals including hatchling quail and larger, chicks, and fish (typically frozen “silver sides” for smaller snakes), all of which can be purchased from commercial suppliers. In addition, the rare keeper who has access to safe-to-consume feeder snakes will also add such prey to the mix when available, since snakes appear to be the foremost prey item for Eastern Indigos in the wild.

Even more recently, Reptilinks [https://reptilinks.com/] have come on to the marketplace, providing commercially available “sausages” filled with processed whole prey animals including frog, iguana, quail, and more. Although some snakes may be resistant to accepting this unnatural food format, Drymarchon in general and Indigo Snakes in particular appear to readily accept them, perhaps with the addition of appropriate “scenting” with previously preferred prey items. (Reptilinks even sells liquid scenting for the purpose, although I have never found it necessary.)

Why the change in dietary approach? One reason is doubtless the more ready availability now, as contrasted with the past, of alternate items such as quail and chicks. But a more significant reason is increased information and awareness about what Indigos eat in the wild. Although multiple studies dating as far back as at least 1944 confirm the varied diet of D. couperi, a noteworthy 2010 study, “Prey Records for the Eastern Indigo Snake” by Stevenson et al set out “… to bring together all available information regarding the diet of D. couperi in an attempt to answer the following questions: What types of prey are preferred? During what seasons/months does D. couperi forage?”

The robust study drew upon data from multiple sources, and confirmed among other facts that “Clearly, D. couperi are strongly ophiophagous” [feed on snakes] and that the “study corroborates the findings of Landers and Speake (1980), who reported that D. couperi preys primarily on amphibians, small Gopher Tortoises, snakes, and small mammals.” The results of the study state: “We compiled 185 separate vertebrate prey records for D. couperi totaling 47 species: 1 fish, 1 salamander, 3 anuran, 1 crocodilian, 3 turtle, 1 lizard, 24 snake, 4 bird, and 9 mammal species … . Anurans [frogs], Gopher Tortoises, snakes, and rodents accounted for 158 (85.4 %) of these records, with snakes accounting for 91 (49.2 %) of the records.” Following these four major prey types, D. couperi diet was also shown to include, in descending percentages: birds, lizards, crocodilians, caudate [salamanders and newts], fish, and invertebrates (with some evidence, as yet not definitive, that neonates tend to consume a significant portion of invertebrates in their diet]. In their conclusions the authors state: “Our study indicates that D. couperi is a predator of a wide diversity of animals, including invertebrates, fish, anurans, salamanders, small crocodilians, turtles, lizards, snakes—including venomous species—birds, mammals, and the eggs of vertebrates.”

The study also makes clear that individual snakes consume multiple species, which D. couperi are capable of foraging for over significant ranges and throughout seasonal changes and varying habits. The evidence is not that individual snakes specialize in a limited set of prey species that varies from individual to individual, but rather that D. couperi in general consume a varied diet.

These and other confirming results begs the question, do captive Indigo Snakes require a varied diet in order to thrive? And here is where some debate continues within the keeper and breeder community. It is clear that Indigo Snakes do not require a varied diet in order to survive and breed, as this has been clearly demonstrated over perhaps half a century or more, and there are breeders and keepers today who continue to feed their Indigos entirely on rodents. The AZA care manual states that, “In zoos and aquariums, D. couperi are normally maintained on rodent prey items,” however the AZA also takes pains to point out that “The manual should be considered a work in progress,” and elsewhere that “…we do not publish “standard” diets. Instead, we provide resources [emphasis per original] to help nutritionists develop diets.” And the AZA Indigo Snake care manual begins its chapter on nutrition with this as part of its description: “Drymarchon couperi are indiscriminate carnivores known to feed on virtually any vertebrate they can overpower.” Clearly, of the wild diet, there is no dispute.

Having said all that, however, there is a difference between “survive” and “thrive,” and increasingly, herpetoculture is moving in the direction, driven by multiple forces and elements within the community, of pursuing and providing the highest possible standards of care for captive reptiles, including all aspects of enclosure size and design as well as husbandry and, of course, diet.

This is not simply a vague wave of the hand toward an ill-defined ideal. Within a remarkably short period of time, knowledge of better husbandry and the tools with which to provide it have undergone remarkable growth. The data from both hobbyists and more rigorous scientific sources continues to pour in concerning a wide variety of species, the true facts of their wild habitat and habits, and rigorous data regarding the results of expanded and improved captive care. Not to mention the ever-increasing emphasis on the value of “enrichment” to render the lives of captive reptiles more interesting and mentally stimulating, in which case a varied diet can also be considered another aspect of such enrichment.

So, while we as yet lack specific data on comparisons between animals raised on strict rodent diets versus those raised on varied diets, we do have, first and foremost, clear and specific data concerning the natural diet of D. couperi, and it would appear advisable—and certainly by no means harmful!—to attempt to duplicate that diet with likely behavioral and health benefits accruing as a result. Keeping in mind that so much of reptile husbandry is a matter of collecting the best available data and then making the best available guess—there can be no compelling argument made against attempting to duplicate wild diets, even if one was to insist that the effort is possibly superfluous—which ultimately seems unlikely.

Also, however, we have increasing observational and anecdotal evidence provided by experienced keepers and breeders that a varied diet produces animals that are more robust, energetic, and produce better breeding results. John Michels of Black Pearl Reptiles makes this explicit claim in their care sheets, to wit: “Although many keepers successfully keep their Drymarchon on a rodent-only diet, I am a firm believer that the snakes are happier and healthier with a varied diet.”

In conclusion, as stated above, I have addressed and included “multiple points of view” and potential controversies, and in that light, I cannot state categorically that you should not keep your Indigos on a diet entirely comprised of mice and rats. However, I do recommend, as others increasingly do, and for the multiple reasons stated—if for no other reason, the interest and variety of experience for the snake—providing a varied diet. I feed my Indigos a regular diet mix of rodents and quail, of appropriate size, as well as chicks for adult animals that can take them, along with supplemental feedings of silver sides or other small whole fish, frog legs, and a variety of Reptilinks, primarily frog and iguana. (On the subject of fish, do not use “feeder goldfish” from the aquarium stores as they are invariably poorly kept and may carry parasites or other conditions.)

Also on the subject of feeding fish: I increasingly see some keepers feed chunks of fresh fish filet, such as salmon or other fish sold for human consumption. I do not at all see the point of this, and I prefer to feed whole animals for more complete nutrition, as would be consumed in the wild. Just because they will take filet doesn’t mean they should. As predators, snakes eat whole prey in the wild, gaining valuable and necessary nutrition not simply from the protein-rich flesh of prey animals, but including calcium from bone structures, and other nutritional elements included with internal organs. By feeding fish filet you are filling your animals with protein at the expense of these other ingredients — especially critically important bone and hence calcium — and with animals that eat once or twice a week, the imbalance in even a single meal of pure flesh is significant. I personally feel that there is no reason at all to ever feed fish filet. All the prey I feed is whole animal, including Reptilinks, and the only exception is the occasional feeding of frog legs, which while not whole animal, contain significant bone.

We cannot leave the subject of feeding without acknowledging that hatchling Indigos can be extremely unpredictable and inconsistent in their initial dietary wants and inclinations. While some neonates will immediately take live pinky mice, or live pinky mice scented with fish, many animals will refuse rodents at first and hold out for fish or even, in some cases, snakes, which appear to be the most natural primary diet for wild Indigos. Scenting with shed snake skins, fish, or frog will often get neonates to start taking rodents, and eventually they can work up to a consistent ease of acceptance without the scenting. Quail are often a favorite food, and neonates can be offered small quail parts at first. One must experiment until the animal eats, and then provide whatever is necessary in order to keep them at healthy weight, while then attempting to transition to more readily available items. All of this takes time and effort and your breeder is the first line of care when it comes to this process. Responsible breeders will generally not ship neonates until they have had at least three rodent meals, and this may take some time to accomplish.

HOW MUCH IS A MEAL?

Most experts are loathe to give precise recommendations for meal sizes, likely because opinions differ, and also, experience matters. Experience makes a difference because veteran snake keepers can judge a snake’s metabolism, behavior, weight, and growth rate, in order to judge feeding size and make adjustments in response to the particular animal.

That said, I will go so far as to offer some general guidelines, but pay attention to your breeder’s advice and don’t be shy about asking questions. That said, here is my simple, minimalist guide:

SCHEDULE
— Feed juveniles every 3 to 4 days

— Feed yearlings every 4 to 5 days until they reach about 3 to 4 feet in length

— At about 4 feet, feed every 5 to 6 days. Watch your animal’s weight, and if they appear to be getting “chunky” at any point, slow down the size and pace of feeding a bit.

— At between 4 to 5 feet, feed every 7 days. This is a good schedule as the animal continues to grow to maximum size.

— At full size, feed every 7 to 10 days. Indigos can go longer, but more frequent small meals are better than infrequent large meals. Indigos are NOT like constrictors!

MEAL SIZE

I feed growing snakes, from juveniles up to six feet, meals based on body weight. I feed a minimum of 10% of the animal’s body weight, and the younger and more growth producing the animal is, I will mostly stay within 15% to 20% of the animal’s body weight. These amounts, and the schedule pace described above, will provide steady and significant growth, without producing obese animals.

The animal’s body shape should not be bulging (except right after a meal) and there should not be much stretched skin showing between scales. In other words, scales should be close together; stretching indicates an animal is overweight. If the body shape seems triangular with a significant angled top edge along the spine, this indicates an animal is underweight. Snakes should be relatively lean but smoothly full bodied. Results will vary with individual specimens, with sex (males get bigger and grow more rapidly), and how much activity and exercise your animals get (I handle my animals very frequently and once they reach sufficient size and relaxed confidence — typically at about a year to a year-and-a-half — I take them outside regularly for exercise on the lawn). Because circumstances vary, if you think your animal is getting heavy, cut down the size of its meals.

Large meals are not good for Indigos as they cannot split their jaws the way most constrictor and venomous species can. Hence prey should not be much larger than the snake’s head, and should be about the same diameter as the snakes body (or smaller). A few smaller prey items makes for a far better Indigo meal than one large item. If your Indigo is taking more than three minutes to ingest its prey item, the prey is too large! Most of the individual items I feed are completely ingested within about one minute and often more quickly than that.

So in general I feed my animals 15% to 20% of their body weight until they reach six feet, and a minimum of 10%. I consider 10% to 15%, on the schedules provided above, to be a safe and healthy diet. That extra 5% produces consistent growth generally without tipping the animal to being overweight, but I will now and then vary the size and time between meals in order to maintain a proper weight range. Although many animals will take food when blue (preparing for shed), and many keepers will keep to regular schedules during this period, I typically stop feeding during the blue phase, to provide a bit of deliberate irregularity and a bit less intake from time to time. In other words, I use the animal’s shedding schedule as a way of consistently varying food consumption.

I also weigh my animals at every shed and in this way can plot weight growth as well as shedding and feeding schedules.

A FEW FEEDING DETAILS

DEFROSTING: Frozen food items can be defrosted in hot water — I typically microwave a jar of water for one minute, achieving a temperature of about 140 degrees. (You don’t want water much hotter than this, as you are using it for rapid defrosting, but you don’t want the heat to cook the prey animal.) I then submerge frozen prey in the water, about 10 or 12 minutes for large mice, rat pups, or weaned rats; button quail defrost a bit more quickly, and larger animals will require more time accordingly. You want to make certain that the internal organs of the animal are completely warmed and that you feel nothing sold or cold in the center of the body.

Defrosting in this fashion adds another level of safety with rodents in that the water serves to soften the otherwise hard and sharp claws of rodents.

RODENTS: In addition, I recommend crushing the skulls of rodents prior to feeding, in order to render them easier to digest, and lower the chance of intestinal blockages.

QAIL & CHICKS: Similarly, I crush the skulls of any bird prey. I also keep small scissors handy to clip the beaks and cut off the claws, again to render them safer to consume and digest.

SILVERSIDES: When tong feeding, try to maneuver things such that the snake will grab the fish by the head, as they go down much more safely, without risk of catching fins and spines internally if the fish is taken backwards. In my experience, if you are feeding from a dish, most Indigos will instinctively seek out the head.

FROG LEGS: Frozen frog legs are readily available in Asian markets. They need to be defrosted and, since they are quite large, I generally split them in half down the center with kitchen scissors, reducing their diameter for ease of ingestion. The cut hip bones at the top of leg are often quite large and sometimes possess sharp edges, and I will often trim this thickness down a bit before feeding.

REPTiLINKS: All of my Indigos, once they are steadily feeding, have readily accepted Reptilinks without the need for additional scenting. Initially I feed them off tongs to assure the snake seizing the link by the end for ease of ingestion. However with minimal experience, Indigos will typically readily take links from a dish.

TONG FEEDING VS. PASSIVE FEEDING: Elsewhere I have discussed the value of tong feedings, which helps to encourage a snake’s predatory behavior and keep their feeding response strong. Also, unlike constrictors which sense the warm body temperature of prey animals, Indigos hunt by scent but also like most snakes are particularly attracted to movement as a predation trigger, so tong feeding will quickly tempt a snake that may exhibit some disinterest in still food. Individuals vary in these behaviors. However, I also like to plant food around the enclosure, up in branches and within cork or cactus tubes, in order to compel snakes to hunt, a form of enrichment that stimulates the snake mentally. Many snakes will be more readily triggered if you feed the first prey item off tongs and then place additional items around the enclosure to be hunted down and consumed.

I will reiterate that prey items should not significantly exceed the diameter of the snake’s body. If it takes more than two or certainly three minutes to completely consume a particular prey item, you should reduce the size. Drymarchon are not like boas, pythons, and other constrictors such as rat snakes and king snakes, that can readily and safely consume prey significantly larger than their own heads. Don’t push big prey items on your snakes, even if they make the attempt or manage to consume such items given sufficient time. Make it easy on them with multiple, smaller items.

How to Feed

Do not feed your Indigo Snakes by hand. You are likely to get bitten, sooner or later, and you do not want to condition your snakes to associate your hand with food. Therefore, use large tweezers for very young snakes, and then once you’re feeding small to medium adult mice, switch to tongs.

It’s advisable to look for large feeding tweezers that have rubber-covered tips, so that a young snake does not injure its mouth or teeth. [See section 16, SOURCES, for these and other recommended items.] Larger snakes taking larger prey are more likely to strike the food more precisely and avoid the tips of the tongs if your placement is correct. An important detail regarding tongs is to obtain non-locking tongs, available from professional reptile suppliers; if you purchase from Amazon or similar general source, you will generally end up buying medical hemostats that latch or lock.

These should be avoided because they are difficult to keep from latching unintentionally, and if this occurs at the moment the snake strikes the prey, you will end up in a tug-of-war, or the snake may simply release the food and may then refuse it following this discomfort. Invest in quality snake feeding tongs; 12” in length will easily serve your purposes until snakes reach about five feet in length.

I am a big believer in “tong feeding,” among other reasons because it helps to establish a clear differentiation between feeding and other interactions. The tongs should only be present for feeding purposes and not at any other time, to help to condition your snake to associate food with tongs, as opposed to hands, and to be able to differentiate, the quicker and easier the better, between feeding as opposed to all other types of interactions.

Indigos are thinking animals that learn such associations quickly. My own rule is to present my snakes with two distinctly different kinds of interactions. Thus I engage in feeding this one way and one way only, every time: I take hold of the first prey item in the tongs in readiness; I then open the enclosure and instantly present the food for the taking. This is always my first step in feeding.

When there are additional food items, depending on the snake I will generally quickly place other food items around the enclosure, in branches or on rocks, so that the animal can gain a bit of enrichment by hunting and finding these items on their own. Or, with wet food like silver sides or Reptilinks, I may simply set the rest of the food into the enclosure on a small feeding dish, and the snake will proceed to find and readily consume these items (believe it or not!).

Some keepers feed their snakes in a separate feeding location or container, thus keeping feeding behavior entirely separate and away from the main enclosure. While I am not persuaded that this makes any difference in preventing potential bites from triggering feeding responses within the enclosure, one possibly valid reason to use this approach is that it prevents the accidental ingestion of loose substrate; that said, I have rarely experienced Indigos accidentally ingesting substrate, as the structure and shape of their mouths is such that it is naturally shorn away as the prey is consumed; what’s more, it seems unlikely that occasional bits will cause any harm as certainly animals consume their share of dirt and debris in the wild.

I do know some veteran breeders and Indigo keepers who adhere to the separate location feeding method, and so I am reminded of John Michels’ words: “If something different works for you, that’s great.” However, I have never used this approach, and while I think it’s a perfectly fine thing for keeping feeding away from the main enclosure, I will address several other related concerns and objections.

One potential concern is that in the case of snakes that are picky or inconsistent feeders, or young snakes that are not yet settled into eating readily and consistently, for my money the last thing I ever want to do is add another variable or potential stressor to the feeding process. Granted, once Indigos are genuinely steadily feeding—not just having taken multiple meals but that have reached the point where their feeding behavior is consistent, predictable, and once triggered, is immediately aggressive without any uncertainty—they are generally not a species that is going to go off food unless there is a medical issue or the behavior is breeding related (i.e. gravid females). But very young Indigos can take awhile before they reach this stage of becoming solid and consistent feeders, and until such time, I am not under any circumstance going to move them from their comfortable resident enclosure or inflict any change connected with feeding.

I believe most Indigo keepers, even those who do utilize separate feeding containers, would likely agree with the above, and probably do not move their young snakes until they are feeding steadily. (If I am mistaken about this assumption, I would be interested in knowing otherwise.)

However, there is another belief I have often heard promoted among keepers of Indigos or other species who claim that tong feeding—which includes encouraging a snake to strike its prey, rather than passively take food from the cage bottom or a dish, or a separate feeding location or container—somehow encourages aggression in the animal’s nature and personality.

This is, in my estimation, fundamentally nonsense, and what’s more, it strikes me as misguided. Your snake is a predator; why on earth would you want to try to pretend it’s a bunny rabbit? The fact is that I want to maintain that natural feeding aggression—emphasis on both words here, feeding aggression—so that the animal doesn’t suddenly stop eating because of the smallest change or disturbance in its conditions or feeding pattern. I want my snakes to be aggressive feeders—which, especially with animals as intelligent and quick to learn as Indigos Snakes, has absolutely nothing to do with the animals being aggressive in any other context. In short: They quickly learn the difference, if you make it clear to them. If you don’t want a predator to act like a predator, don’t own a predator. Get something predators eat—a gerbil, hamster or a rat—and keep that as a pet instead. Do not inflict your own fears and biases on your innocent captives.

Tap Training

Most experienced snake keepers (and this applies to many species) can be readily “tap trained,” meaning that when you are about to engage in any non-feeding interaction, and you wish to quickly disarm the snake’s feeding behavior, you gently—very, very gently and briefly—touch (it’s really a “touch” rather than a “tap”!) the snake on the nose with a snake hook (and don’t use a hook any heavier than is necessary for the size of your snake; light compound hooks are preferable to weighty metal hooks). Snakes in general and Indigos in particular will quickly learn that this touch of a hook means there is no food, and thus their feeding trigger is instantly negated.

This is a fascinating phenomenon to see with Indigo Snakes, and it doesn’t take them very long to figure it out. If my Indigos are hungry, they are generally out front looking to be fed, and when the enclosure is opened you can clearly see (once you know how to recognize it) that they are alert, energized, and poised for the kill, as it were. (If you’re not careful, some may even come rocketing out of the enclosure as if launched!) And, if you are not very careful in this instant, you will get bitten—but it is important to understand that this is not an act of aggression, or fear, it is a feeding response. However, in this instant, if you touch the snake with the hook, you can see them stand down. They instantly calm down, and their entire body posture alters. In essence, they relax.

Because of the potential for a swift feeding reaction, it is wise with Drymarchon to use a hook as first contact, not only to “tap” but also to pull the snake from its location, and partly out of the enclosure. The combination of the tap and the hook means that in the seconds between the initial contact and getting the animal in your hands, it knows already that feeding is off the table, and it will remain calm and prepared to be handled. It is wise to make this a firm habit with Drymarchon, because a bite, no matter the cause, can be a painful and messy thing, thanks to sharp teeth and the unusually strong jaws of these particular species. Better safe than sorry. Make the hook a safety habit.

To make my approach completely clear, if I am feeding, I make sure to be able to instantly present food, on tongs, the moment the enclosure is opened. The animal’s feeding response is properly triggered, and the meal ensues.

However, if I am not feeding, I make sure to keep tongs entirely out of view, and if my intention is to handle the animal, I will typically promptly introduce the hook for a tap or a body touch or both, and then put it aside. However, oftentimes if my intention is to do spot cleaning, water replacement, substrate maintenance or any such task other than handling, then I use my judgment as to whether or not to tap or touch before proceeding. If the animal is up and active and seems prone to a feeding response, I will tap or touch in order to disarm that. However, because my animals are accustomed to food only being an instant presentation upon opening the enclosure, most of the time my snakes relax the moment I start doing anything in the enclosure that is not feeding or handling. In other words, the simple fact of delaying—the lack of tongs and food being presented at all—more often than not will cause the animal to recognize within a few moments that this is not a feeding interaction, and so even without tapping or touching or moving them, they will visibly relax and ignore me, or watch what I am doing with some curiosity, but without any feeding response being triggered. While it is true I am taking a small chance in these situations, the delay is typically enough for the snake to recognize that this is not a feeding. But under the heading of better safe than sorry, depending on the size of the enclosure, tap or touch is always the safer way to make sure you have given the animal a clear message, and that it has not missed the intended message.

So, my experience (and the experience of many others) clearly demonstrates that if you distinctly separate feeding from other interactions, and also “tap train” your Indigo Snake, there is neither need nor provable value in moving a snake to an alternate feeding location. That choice is yours, but my choice is to avoid this procedure entirely.

Target Training

Finally, while the kind of training I have described is minimal and straightforward – and quicker and easier for Indigos to apprehend than for many other species, although most will eventually, with consistency, get the idea—there are more detailed, nuanced, and varied forms of training snakes available to you, and thanks to their ready intelligence and visual acuity and attentiveness, Drymarchon should likely respond to these methods well. Operant conditioning, commonly known as “target training,” has long been used with wild animals in professional zoos and aquaria, in order to train animals not merely to do performance behaviors, but to create and command behaviors that are useful for facilitating care procedures and reducing stress in necessary captive maintenance procedures. Thus, for example, many animals are trained to move or “shift” between enclosures as needed, to submit to certain kinds of handling for medical care, or to enter into specialized containment for veterinary procedures, medications, examinations and the like. The term “target” refers to the fundamental tool of training, which is generally some form of a colored ball or similar, too-large-to-swallow object on the end of a stick, which the animal is trained to follow or touch with its nose or some other body part when presented, in return for which the animal receives a food reward. Once the target training is achieved, the target is then used to build beyond the basic contact into more elaborate, multi-step behaviors.

While these techniques have been used for decades with mammals and birds, increasingly we are finding that such techniques can be used for an extraordinary array of animals, as we move down the evolutionary ladder to species traditionally regarded as less complex or intelligent. And currently there is increased awareness and interest in using these techniques with many reptile species. For further information about target training snakes and other reptiles, I refer you to the work of Lori Torrini, and her YouTube channel [https://www.youtube.com/c/LoriTorriniAnimalBehavior] and also Reptelligence.com and their associated YouTube videos. The value of target training snakes is multi-faceted; with giant snakes and venomous species, it makes sense to train an animal to move from one enclosure to another space or container with a minimum of direct handling, or no direct handling at all. The usefulness in these instances is unarguable. But there is something to be said for the notion that training any snake can be fun and interesting for the keeper, and enriching and mentally stimulating for the snake. I therefore encourage your further exploration of target training and its techniques, the details of which are beyond the scope of this site’s focus.

Permanent Home Enclosures for Adult Indigo Snakes

As with every aspect of reptile husbandry in recent years, ideas about enclosures, and available options, have significantly evolved. The first question when it comes to large snakes like Drymarchon, as well as larger boas and pythons, is “How large an enclosure is needed?” And the answer has definitely changed in recent years.

Along with the increasingly operative assumption that reptile keepers should strive to approximate a naturalistic living conditions as possible, while acknowledging that the actual space limitations of captivity are by definition extremely constraining, increasingly there is a trend toward enclosure sizes that allow a snake to stretch out for its entire length. While there is debate about how routinely snakes do this in the wild, there is increasing evidence that given the opportunity, they will extend their entire length from time to time.

Two leading contemporary rule-of-thumb recommendations concerning enclosure size for adult snakes are:

• 1) The length of the animal should be equal to the length plus width of the enclosure. So an enclosure that is six feet by two feet is appropriate for an eight-foot snake.

• 2) The length of the snake should be equal to the diagonal length of the enclosure. So an enclosure that is six feet by two feet is appropriate for a snake that is seven feet, four inches in length.

So you can see that while both of these formulae produce somewhat similar results, the diagonal guideline clearly requires a larger enclosure for the same size snake. By comparison, the diagonal of an enclosure that measures eight feet by two feet measures eight feet, four inches.

In November of 2021, the Federation of British Herpetologist (FBH) issued their 44-page Code of Practice for “Minimum Enclosure Sizes for Reptiles,” probably the most progressive and thorough such set of standards currently available (albeit which still has its vocal critics), from which I will quote at some length. In the document’s opening pages, under the heading “Rationale,” the document states:

• “There is little published research into the link between enclosure size and wellbeing in reptiles kept in captivity. Research studies into whether enrichment affects the welfare of corn snakes, leopard geckos and bearded dragons showed that welfare improved when enrichment was added to the enclosures. These studies all used enclosures similar to or smaller than the minimum enclosure sizes listed in this document for these species. This indicates that enrichment plays an important role in the welfare of reptiles and that these benefits can be achieved in the minimum enclosure sizes recommended in this document.”

And further, from the Introduction:

• “The sizes are described as multiples of the animal’s size—for lizards this is Snout to Vent Length (SVL), for snakes it is Total Length (TL), and for chelonia this is Plastron Length (PL), although we also discuss Straight Carapace Length (SCL). The dimensions of enclosure sizes are stated as width x depth x height, and for species that are truly arboreal the longest dimension can be the height of the enclosure to provide climbing space.

• While there is little available evidence to demonstrate the causal need for a snake to stretch out to maintain its health, there is a growing evidence base that given the opportunity, snakes will at times nearly fully stretch out, even if adopting a completely linear posture may happen very rarely, if at all. Therefore, permanent housing should provide the option to fully stretch their body should they choose to do so. One dimension inside the enclosure should always be at least as long as the snake. This could be the width, depth or internal diagonal and for terrestrial snakes must be at floor level. Generally, the recommended minimum enclosure size for snakes is 0.9 x 0.45 x 0.3 (W x D x H) times the snake’s length. This ensures the internal floor diagonal is 1 times the length of the snakes.”

That minimum enclosure size for snakes applies to Colubrids, which are broken into three sub-groups in the report, based on the activity level of the species. Drymarchon are classified in Colubrids Group 1, least active, with the minimum enclosure size per the formula recommended above. Thus, in keeping with our example of an eight-foot long snake (the size of a large male Indigo Snake), the recommended enclosure size would measure 7.2 feet long by 3.6 feet wide by 2.4 feet high. Obviously the floor dimensions can safely be somewhat redistributed, for example 8.2 feet long by 2.6 feet wide.

Moving to Colubrids Group 2, more active snakes such as Gonyosoma (Red-tailed Green Ratsnake) and Spilotes (Tiger Rat Snake), the recommended minimum enclosure size moves up to 1.2 x 0.5 x 0.3, which in the case of our eight-foot long snake example results in a recommended enclosure that is 9.6 feet by 4 feet by 2.4 feet high.

Throughout this consideration of the FBH recommendations I have provided samples as applied to an eight-foot long snake. In fact, adult male Indigo Snakes will typically reach lengths of between seven and eight feet, and occasionally a bit more, while females tend toward reaching about a foot less, reaching between six feet and seven-and-a-half feet at adult size. Thus the examples I have cited apply as recommended minimum enclosure sizes for adult Indigo—namely, enclosures comprising a minimum of six feet in length using the oldest standards, and eight feet in length by the best contemporary standards.

In other words, be advised: If you plan to keep Eastern Indigo Snakes, you should plan on adult permanent home enclosures in the range of eight feet in length, or more.

You can download the complete paper here: FBH Recommended Minimum Enclosure Sizes

Enclosures for Juvenile and Sub-Adult Indigo Snakes

Indigo Snakes grow quickly in captivity, and private keepers will generally lack the resources to provide high quality, maximal sized, naturalistic enclosures for their young snakes. This is where we begin to address the subject of plastic bins, known variously as sweater boxes, Really Useful Boxes (RUBs) in the UK, and in the herpetoculture world: TUBS.

Plastic tubs are often a necessity when keeping neonate, juvenile and sub-adult Indigo Snakes, as mentioned because of their rapid growth. I am not opposed to tubs for juvenile animals and use them myself, moving snakes to progressive largely containers, from 6 quart to 15 quart to 32 quart to 60 quart as they grow from neonate to sub-adults of between four and five feet in length, at which point I would move them to either to interim PVC enclosures of four to six feet in length, or directly to their full-sized forever enclosures. I do not use conventional commercial “rack systems” but rather buy these kinds of containers retail, which are typically used for shoes, sweaters, under-the-bed storage and the like and are readily available from national retail chains like Target and Walmart. I generally use the Sterilite brand [https://www.sterilite.com/category-page.html?S=1#TOP], which are transparent and come with fitted lids held by hinged latches at each end. (I add weights to assuredly prevent escapes.) I then ventilate these containers with the use of an inexpensive soldering iron, burning small holes in multiple rows along the ends of the containers and typically along the long sides as well.

Before I address the controversies over and objections to plastic tubs, I must make this important point: What is most important about enclosures, other than size, is what goes in the enclosure! Whether you are using an expensive PVC or “Vision” cage with glass fronts, a fish tank with a screen cover, or a simple plastic tub, the type of enclosure does not define how you equip it. This means that the use of plastic tubs does not prevent you from providing a quality environment that includes one or more suitable hides, branches and other environmental variety, along with proper heating and UVB lighting. The use of a tub is not an excuse to provide little more than the minimal requirements for survival. Snakes require variety and stimulation, security and cleanliness — not just mere food and water. Remember: the goal is help your animals not merely to survive, but to thrive.

As mentioned, I do not use commercial rack systems. Although not as good as halogen radiant heat lamps, which is definitely what is recommended for heating (from above) for your eventual permanent enclosures, I use heat tape for my tubs, controlled by computerized thermostats. And I provide UVB lighting via reflectors hung above the tub, not resting on the lids. You may have heard that UVB lighting does not penetrate polystyrene plastic tubs. This is a myth! I will address these issues further in the heating and lighting sections of this husbandry page.

However, here is an excellent video from Lori Torrini about how to equip plastic tubs with sliding doors, heat lamps, UVB, and naturalistic environments. This is well worth your attention:

Heat & Light for Tubs

And here is the source for the sliding door and other gear to upgrade tubs:

Specialty Enclosure Designs

Traditional Glass Enclosures

For juvenile snakes I do use tubs, with enriched environmental elements and UVB lighting, so that I can economically progress my animals up through very sizes of enclosures as they grow. However, another quite suitable approach if you have the space and resources is to use all glass aquariums with screen tops. I do think neonates do better in tubs so there is less visual stimulation until they have developed into consistently strong feeders and somewhat confident animals. But once that happens, I would certainly encourage the use of, for example, a 20-gallon “long” aquarium tank for juveniles, with UVB and heating lamps above the screening. This setup won’t hold any humidity so it might be necessary to close off some of the exposed screening, and/or provide some judicious periodic light misting. But once animals are confident, this a very good enclosure plan that can also progress to a 30-gallon “long” until such time you move specimens of about 4 feet in length into PVC enclosures of 4’ x 2’ x 2’ and then continue to expand until full adults are preferably kept in 8’ units.

Rack Systems

Obviously, I cannot leave the subject of enclosures without addressing commercial rack systems. Many hobbyists will object to my conclusions and recommendations regarding this subject. I will begin by stating my position clearly:

In general, I believe that rack systems are no longer acceptable for use by home reptile hobbyists and collectors.

Rack systems could, and should, be described as sensory deprivation enclosures. Most keepers and commercial breeders alike keep snakes in the most minimalistic conditions when it comes to racks, providing little more than proper temperature, a water dish, and perhaps a humid hide for certain species. If your goal is to genuinely help your snakes to thrive, rather than survive, then it should be obvious that these conditions describe little more than the means to survive. We, as reptile keepers, need to do better. The days of collecting racks of tubs in home collections should be relegated to the past, representing a time when we knew far less about how to provide the very best husbandry for our captive creatures. The time to end rack systems for home collection is right now.

Unfortunately, that day will not come today. While there is an increasingly well-informed and vocal contingent promoting this new school of husbandry, with more and more scientific research materials accumulating that support this approach in order to keep animals at their very best potential health, there is great resistance to achieving such a sea change in thinking. This resistance comes from and is maintained by powerful and influential aspects of the industry, particularly large retailers and breeders, who want hobbyists to continue to think that part and parcel of keeping reptiles is to collect dozens of species and specimens in their homes. The only way for most private keepers to fulfill that appetite for collecting is to rely on rack systems, for reasons of both space and cost. Most people lack the financial resources and the housing space to keep large numbers of snakes in the sizes of enclosures that meet the minimum enclosure size recommendations discussed above, as defined by current FBH professional standards.

An aside: I recently watched a several years-old video of a hobbyist who has kept venomous snakes at home for many years, offering instruction on how to handle them for purposes of enclosure maintenance. While it was clear that the keeper was knowledgeable about his animals and kept them in ways that were long considered reasonable and typical in the past, seeing this array of cobras and pit vipers, all in “20-long” glass aquarium tanks with screen covers, newspaper, a water dish and a hide, was appalling. These animals are being given the minimum of what it takes to survive, and they will do so for a lifetime. But they are living in conditions of sensory deprivation, with no means of exploration, movement, variety, or mental stimulation. These conditions are the product of a time when snakes were thought to be mindless primitive robots controlled entirely by instinct. We now know that this description is entirely false and untrue—it is, quite simply, wrong. When we face up to the fact that we are keeping thinking animals that are capable of learning from experience and responding and interacting with their environment accordingly, we must acknowledge that the days of bare tanks needs to end now, and that such “survival” care essentially qualifies as a form of cruelty to animals. I am not opposed to keeping reptiles. I am an advocate of keeping them responsibly in conditions that are intended to help them in every way possible to thrive.

So, what is it going to be? The choice is yours, and you are responsible for making it. Do you want to keep animals that are surviving, or that are thriving? Do you want to collect, or truly connect? I believe that hobbyists need to face the authoritative, scientifically supported knowledge that we now possess—with more constantly on the way—that we cannot do both, that most of us simply cannot collect large numbers of snakes and provide them with the highest possible standards of care that are not merely recommended, but in fact, at our growing stage of knowledge, required.

But before leaving this subject, we do need to address the subject of commercial breeders and hobbyists who breed in significant volume. For these keepers, rack systems would appear to be a must; there is no practical alternative. And without commercial breeders, the hobby would diminish, because availability of species and varieties would be reduced, and prices would rise with the accompanying scarcity. And frankly, for better or for worse, we are not going to be able to force breeders out of the business. There will always be large-scale commercial breeders, and they will rely on rack systems to house the bulk of their animals.

So from my vantage, what we can hope for—and yes, if wishes were horses only beggars would ride—but nevertheless, what I think we can hope for when it comes to the use of commercial rack systems is that the overwhelming majority of animals kept in this manner are typically young animals that are offered for sale relatively quickly, where they will then go to homes in which responsible keepers will provide optimal care. We can also hope that responsible breeders will keep their adult breeding animals in larger enclosures, which obviously is a condition that is highly variable between breeders.

I am very much in agreement with this opinion piece written by Paul Barclay, the found of Custom Reptile Habitats, and I recommend reading and sharing it:

Do You Use Reptile Racks? If You’re Not a Breeder, Read This!

I sometimes watch videos by Kevin McCurley of New England Reptile Distributors (aka NERD). Despite being one of the largest commercial snake breeders and retailers in the country, in many ways Kevin appears to remain a hobbyist at heart, as his passion and joy and appreciation for animals clearly shines through, and I believe sincerely so. He has been breeding snakes for many, many years, since the 1980s in fact, and he possesses a wealth of knowledge that I often find fascinating and educational. And he is an extremely skilled reptile handler.

That said, NERD keeps roomfuls of snakes in racks, including remarkable quantities and varieties of ball python morphs, among others. Again, one hopes that most of these animals are not permanent residents, but rather intended for sale. And NERD also keeps entire rooms devoted to large snakes, and venomous snakes, in substantially sized display enclosures rather than racks. All of this is by no means an ideal arrangement for all of these animals, but if someone is going to keep a sizable commercial breeding operation, I would rather it look like NERD’s than many others I have witnessed.

I do sincerely hope that market pressure, and cultural pressure within the herpetoculture community, continue to press both hobbyists and breeders alike toward an ever improving standard of care, and that there will come a day when we will look back at rack systems much the way we look at commercial “puppy mills” today. I also think that this will require a sea change in attitudes that will have to be encouraged, rather than forcibly compelled.

In my personal experience, Indigo Snake keepers and breeders have something distinctly special in common, possessing a shared passion for these regal, majestic animals that are truly “lords of the forest.” And whether or not the most strident and progressive keepers are willing to accept this statement as fact, I believe that this affection and passion also applies to the handful of commercial breeders of Drymarchon and D. couperi that I have personally encountered, including those who may rely on rack systems. Spend time with these individuals and you come face to face with passionate people who think there is something special and magical about these species, and genuinely care about their welfare and their futures. You may differ in this opinion, and I may differ with them in what I consider required care considerations for my animals and yours, but I have gleaned countless reams of knowledge from longtime experienced breeders, and their brimming fountains of experience and expertise—not to mention, fantastic animals of the greatest possible quality. There is much to be said for drawing on the experience of others, while each one of us is then free to follow our own paths.

Finally, while much of the argument for larger and more naturalistic enclosures, diet and other conditions are based on assumptions and goals that are logical and intended to provide the best imagined conditions using nature as a model, regardless of whether there is definitive evidence of such requirements, nevertheless it should not be imagined or argued that such evidence is as yet absent. In fact, scientific evidence continues to rapidly accumulate in support of such standards, and away from old school husbandry. I will cite here just one significant paper from 2021, based on carefully designed testing protocols comparing the health and behavior of ball pythons kept in naturalistic terrariums versus rack systems. The paper posits that:

• “… the housing environment should be designed in a way that always allows the animals to express their natural behavior repertoire and to cope with all arising challenges. Moreover, enriched housing conditions can evoke positive emotions, which cause improved wellbeing and contribute to solving behavioral problems. The aim of the present study is a scientific, comparative evaluation of ball python husbandry by considering animal welfare aspects when housing these animals in a rack system or a terrarium.”

And among the study’s conclusions:

• “In summary, our study results show that based on the assessed aspects, the housing in a rack system cannot be considered an animal-appropriate accommodation for the ball python. The only animal-based advantage of rack housing is the possibility for complete and fast cleaning. This aspect can be useful for keeping sick animals or facilitating quarantine conditions. Further aspects such as the keeping of many animals in small spaces or the timesaving maintenance of these animals are in no case in the interest of the snakes. These conditions are rather reminiscent of intensive mass husbandry, in which economic aspects are considered to be of higher priority than animal welfare.”

I strongly encourage you to consult the original paper here: Animal-Appropriate Housing of Ball Pythons

Here is another pertinent article about observation snakes stretching out to their full length. While not a definitive study, the abstract states: “We conclude that future policies for snake husbandry require a paradigm shift away from an erroneous belief system and toward recognizing the greater spatial needs of these reptiles.” SEE: Spatial Considerations for Captive Snakes

In conclusion, we should be very clear: the current new school thinking and goals of reptile husbandry are not based merely on wishful thinking or the dreaded “anthropomorphism,” but rather on a steadily increasing data stream in support of concrete evidence and conclusions of what truly encounters quality care, versus standards of care that are quickly being rendered as indefensible in today’s information-rich world of herpetoculture.

If one reviews the literature for recommendations concerning substrate for captive Indigo Snakes, one will readily gather a list of potential candidates that include:

• Small animal paper pellet litter (i.e. compressed pelletized paper)

• Newspaper or brown paper

• Aspen shavings

• Pine shavings

• Shredded bark mulch

• Various small animal bedding products

• Various horse bedding products

• An absorbent bedding mixture of wood shavings and pelletized wood pulp or paper pulp.

• Variable blends of potting soil, sphagnum moss and the like.

None of these possible substrates is perfect, and each comes with its own potential advantages and concerns.

As mentioned elsewhere in these husbandry materials, Drymarchon in general and Indigo Snakes in particular have high metabolisms, eat frequently, and accordingly, defecate frequently. Their defecations tend to be more liquid and messy than many other snake species, and larger animals produce unpleasantly messy deposits that many keepers will say also tend to possess a much more unpleasant smell as compared with other species. As a bonus, some animals will manage to spray their defecation along the sides of their enclosures, and many are in the habit of routinely defecating in their water dishes.

Yet at the same time, Indigos are particularly sensitive to their enclosure conditions. They do not like the smell of their own waste, and they will attempt to withdraw from it or escape. Meanwhile Indigos also require a stable humidity in the range of 60 to 70 per cent, and if kept significantly lower or higher, serious health issues can result. And they require a steady supply of very fresh water; even 24 hours without available water can lead to long-term renal problems and death, and many Indigos will refuse to drink fouled water.

All of these facets of Indigo snake behavior and requirements must be seriously considered before committing to bringing Indigo snakes or other Drymarchon species into your home collection. These are not a forgiving species if these conditions are not strictly met. This is not a python or boa or rat snake that you can safely ignore for weeks at a time with potentially no harmful results, merely providing adequate heating.

So when it comes to substrate, the choice is a balancing act between various requirements, and keepers must make their own best decisions, keeping in mind above all what they are willing and capable of achieving in the standard of care being provided. As Black Pearl Reptiles state in their Drymarchon care sheet: “There’s no right or wrong answer here—it’s just a matter of finding a substrate that works for you.”

Here I will address these various options grouped in categorical terms:

(1) Newspaper and brown paper are inexpensive and simple. As mentioned elsewhere, Carl Kauffeld pioneered the recommendation and popularizing of newspaper as a snake substrate, and in the 1970s and ‘80s that is what I routinely used and recommended, and there is no doubt that snakes can be successfully kept on paper. The defining fact here is that paper does not absorb any quantity of feces or urates whatsoever, and hence what is absolutely required is immediate cleaning and replacement of the paper every time a snake defecates. Many keepers prefer this approach because paper is cheap and cleanup and replacement is quick and easy. Newspaper is an unarguably safe and convenient approach, as clearly demonstrated by the fact that some of the most experienced Drymarchon breeders rely strictly on newspaper.

The downsides are that, obviously, paper is not natural looking and not particularly attractive for showing off your animals in their enclosures. And again, since there is no absorption, cleanup must always occur immediately upon the paper becoming soiled, without delay.

A more significant negative is that paper is dry and cannot hold humidity, hence it is difficult to keep the humidity up in the 60 percent range (but not more than about 70 percent; Drymarchon are not tropical species and constant excessive humidity can lead to respiratory and skin infections). Keepers must address the need for reasonable humidity, which can be achieved with regular spray misting, but more typically and manageably it is best (when using paper substrate) to provide a humid hide box, filled with wet sphagnum moss and a single entry/exit hole (to maintain humidity and prevent rapid evaporation).

(2) While soil, moss, aspen mulch and bark substrates look natural and do hold humidity, they come with concerns as well. It’s difficult to keep these substrates clean, especially with the notable output of Drymarchon, and so constant attentive spot cleaning is a necessity. All of these naturalistic substrates run the risk of retaining too much moisture and resulting in excessively high humidity, which is difficult to reduce unless your enclosures are thoroughly ventilated. Frequent spot cleaning is required to address the mess; high ventilation is required to keep humidity at a manageable level; and some keepers choose to feed their animals outside of the enclosure in order to avoid ingesting substrate materials. (As mentioned however in the previous section on feeding, I have personally never found this to be of particular concern with Indigos.)

(3) Pelletized paper small animal litter can be an excellent substrate for Indigo snakes and Drymarchon in general. I recommend unscented “Full Cheeks” Odor Control Small Pet Paper Litter & Bedding available at PetSmart. The reasons for this are multi-fold:

• Paper pellets do an excellent job of absorbing moisture. They take it up instantly, and while the pellets swell with the moisture, they remain damp but not wet. Most liquid is immediately absorbed, and spot cleaning is an easy task.

• They are treated, but not chemically, to reduce odor with small animals and they do an excellent job of this odor reduction. While not by any stretch natural in appearance, they are not as unnatural to the eye as paper and so the appearance is not unpleasant or distracting to the eye.

• Due to their shape and size, combined with the shape and characteristics of Drymarchon mouths, even when pellets briefly adhere to wet food, I have never seen an Indigo ingest a single pellet. They simply sheer off at the edge of the snake’s mouth as it completely ingesting food items.

For all of these reasons, I find pelletized paper a useful substrate. One admitted concern is that for keepers with large numbers of animals, this kind of litter can become costly. For small collections, the benefits well outweigh the costs.

(4) Note however that some leading breeders have had success using a combination of substrate, such as large aspen shavings with either a scattered top layer of paper pellets, or a homemade blend of about two parts shavings to one part pellets (by volume, not weight). The pellets immediately soak up liquid and so with spot cleaning the substrate does not have to be entirely cleaned and replaced as frequently as with shavings alone or paper. Also the shavings provide a more natural appearance, allow animals to burrow if they wish, and the shavings absorb liquid that can occasionally drain through the pellets alone and collect on the bottom of the enclosure without being fully absorbed. I have at times used pelletized paper entirely, but have since come to rely on this kind of mix of aspen shavings and/or kiln-dried pine shavings with pellets for most of my animals and enclosures.

This kind of mix was initially suggested to me by Robert Bruce and I have come to rely on it as I find the combination renders all defecations completely dry in short order, and the results are easily spot cleaned, without requiring frequent changeover of the entire substrate.

Many keepers express the concern that most natural or what might be called semi-natural substrates run the risk of ingestion during feeding, which can lead to disastrous cases of impaction. I frankly question the legitimacy of these oft-repeated concerns. Surely snakes in the wild invariably ingest dirt, sand and the like in the course of their lives, likely without negative consequences. The way snakes eat and the shapes of their mouths seem to exclude much if any adhesion and ingestion of substrate in my experience. Despite this oft-repeated concern, I often think there is a kind of “helicopter parenting” phenomenon today among younger reptile keepers, reflecting a phenomenon seen in the wider culture of child-rearing, and that among keepers leads to an obsession with cleanliness that ignores competing factors. (For example, measuring now common recommendations for quarantining new snakes, while ignoring the extreme stress of such conditions, when in fact what you want a new snake to do as soon as possible is to successfully adapt and feed well and regularly.) As far as I am concerned, Snakes are wild animals. They live in dirt. Deal with it.

It should also be mentioned here that there is much folk wisdom husbandry about the alleged dangers of pine shavings. However I have found no scientific evidence to support this, as opposed to the long term practical experience of more than one veteran breeder who have consistently found pine to be safe. Note however that this refers strictly to kiln-dried pine shavings.

For sake of completeness it should also be mentioned that significant humidity is particularly important with neonates, and so John Michels likes to keep them entirely on aspen mulch for the first few months while in small shoebox tubs, at which point you can begin to mix in the paper pellets, gradually changing them over; Robert Bruce, on the other hand, keeps neonates strictly on pelletize paper in order to prevent the young from getting in the habit of burrowing. Either way, whenever possible with young Drymarchon, make every change of conditions as gradually as possible, lest you find your animal suddenly refusing to eat and needing to lure it back to steady feeding.

(5) Bioactive or semi-bioactive setups are increasingly coming into fashion for herptile enclosures, especially for amphibians, Old World Chameleons, and other species that require high humidity, which is readily maintained with relatively deep soil substrates. Bioactive is generally taken to mean a reptile enclosure (terrarium, vivarium, etc.) that includes natural substrate, live plants, the cultivation of aerobic bacteria, fungi, and a population of “microfauna” comprising a “clean-up crew” of small invertebrate species like springtails and isopods, all of which contribute to breaking down waste products produced by the captive reptiles or amphibians; in effect, a self-contained, somewhat self-cleaning and self-maintaining miniature ecosystem of sorts.

Bioactive enclosures are a significant force in the current evolution of home herpetoculture, and more and more species of reptiles are being successfully kept in such environments, both in private amateur and public professional collections. When it comes to larger animals, like Drymarchon among many others, the jury is still very much out on bioactive, with more questions than answers being readily presented in the current scene. There is a small vocal contingent that insists that not only can such large, high metabolism species be successfully kept in bioactive enclosures, but that a phenomenon sometimes dubbed “simple bioactive,” which discards the inclusion of the “cleanup crew” of invertebrates, dispenses with a drainage layer at the bottom of the substrate, and simply relies on a prescribed mix of basic soils combined with periodic replacement of water in the substrate, yet supposedly requires no further maintenance or significant manual cleaning. The mainstream practitioners of bioactive husbandry have met these claims with significant skepticism, and it is fair to say the jury remains out concerning such practices, along with the idea of keeping large snake species in any kind of bioactive or semi-bioactive enclosures, much less creatures that eat and defecate at the pace and volume of Drymarchon species.

I, for one, am not currently qualified to draw or offer conclusions in the realm of bioactive enclosures. I remain somewhat skeptical but interested in the possibilities, not only because such systems may provide for reduced time and effort devoted to maintenance, but most of all because natural looking habitats that include deep substrate provide for and stimulate more natural behavior of the captive animals in our care. There is no doubt that I would like to be able to provide my Indigo Snakes with the opportunity to tunnel and burrow at their own natural inclination. As yet, I am unable to confidently make this leap while maintaining my snakes at a level of quality care that meets my demanding requirements. Time will tell, and this may yet change in the future.

Since humidity is a somewhat less critical and more readily managed issue with Indigos than light and heat, I will address humidity first. In short, Indigos thrive at a relative humidity of between 60 and 70 percent. Higher than that, according to conventional wisdom, may risk external conditions like blisters or other skin issues. Lower than that may result in dry sheds, potential digestion issues, and general poorer health in general.

This is an easier range to maintain however than species which require particularly high humidity of 85 percent or more, and for which humidity is a potentially critical issue. With Indigos, complex or mechanical solutions are generally not required in order to maintain a safe humidity range.

With smaller specimens in tubs, I maintain humidity entirely by passive means, balancing the amount of ventilation with the amount of water routinely present for hydration. As mentioned in the section on enclosures, I use a simple soldering iron to ventilate tubs. After putting a couple of rows of holes along the upper portion of the two long sides, I set up the tub with a water bowl and then monitor the humidity with a standard reptile hygrometer for the next few days. As necessary, I add further ventilation, and experiment with the size of the bowl, until settling in at a stable balance in the 60 to 70 percent range of relative humidity. Assuming you are successful at establish a stable range, then a humid hide should not be a necessity. However, if you live in a particularly arid climate where it is difficult to maintain the necessary degree of humidity, then humid hides are advisable. A translucent or opaque plastic container filled half way with quality sphagnum moss that had been thoroughly soaked through, but does not leave additional standing water in the container, serves nicely, with a smoothly cut hole in the center of an opaque lid, does the job nicely.

John Michel’s of Black Pearl, who lives in a fairly warm and arid climate, keeps this type of humid hide in every tub for snakes large than neonates in shoebox size containers. However he believes a somewhat higher humidity is valuable for neonates and to help them to get started feeding, so he uses a natural smaller grain bark as substrate, which will serve to maintain the humidity. All that said, Robert Bruce does not keep humid hides in his tubs, however in the case of both of these breeders, the difference is likely due to whatever humidity they are able to maintain in the larger building structure that houses their reptiles. Once Indigos reach sub-adult or adult size, humid hides are probably advisable, allowing the animal to self regulate, along with regulating its temperature and UVB exposure in a properly equipped enclosure.

Other ways to maintain humidity are to spray the interior with a hand mister periodically, although not so much that the enclosure does not completely dry out in about 24 hours. You can also spray your snake directly, and many, though not all, seem to enjoy a gentle “rain shower.”

Many snake keepers are in the habit of “soaking” their animals periodically, in a container or closed bucket with several inches of comfortably warm water, making certain the animal can manage its body in order to keep its head readily above the surface. Opinions differ as to whether soaking is necessary for Indigo Snakes. The two breeders mentioned above do not routinely soak their animals. Other breeders maintain that they find soaking gravid females helpful in preventing egg binding.

In my own case, I tend to soak my snakes once or twice when they are in blue or opaque phase prior to shedding. I find I never have dry shed issues or a necessity for assisted sheds. With tubs, once a snake is blue I will change the size of the water dish to a larger version, which will in turn slightly raise the humidity. It should be noted that given the opportunity snakes will tend to self regulate their hydration needs, and may curl up in their water dish—which the larger dish in this period helps to facilitate—and if presented with humid hides may spend more time in them as ecdysis approaches.

If your snakes are consistently shedding well you can likely assume that your humidity level is healthy and serving your animals well. If you encounter dry sheds, or enclosures in which condensation routinely forms on the glass or other interior surfaces, or the substrate is obviously damp, then it’s fair to say that the humidity is either too low or too high as the case may be, and steps should be taken to finer tune and stabilize these elements of the conditions.

If there is some disagreement among D. couperi keepers concerning diet and substrate, the disputes increase when it comes to the subjects of heating and lighting. A significant part of the reason for this is that so much of the current state-of-the-art information in both areas is extremely recent, and still currently evolving. And simultaneously there remain forces resistant to making the kinds of changes that are currently being advocated within the new wave of herpetoculture.

Firstly, people are always resistant to change. There are people in the industry—not many, but definitely some—well regarded as experienced experts, who have been keeping snakes in general, and Drymarchon in particular, for decades. And so it is natural to say: Why argue with success? Why change what doesn’t appear to be broken?

And indeed, as previously mentioned with regard to diet, there is a long record of success not only keeping but breeding Indigos, with longstanding standards of rodent diet, varied substrates, basic heating and minimal lighting, not to mention four-foot-long enclosures for adult animals. And, so far, there is a dearth of rigorous data establishing that such care produces distinct negative impacts.

But as previously addressed, there is a difference between survival and the very best possible quality of captive life. Between these two standards, we must admit that even if we argue for change and improvement we are invariably making best guesses, and extrapolating from personal speculation, along with what pertinent science may as yet exist. And in some cases, often the most strident insistence on what is “required”—what I have dubbed the “One True Way” proponents—is based on what might be called anthropomorphism and empathy at best, and untethered folklore husbandry at worst, which actually exists at both ends of the husbandry spectrum, both minimal and maximal as well. Those who are insistently unwilling to accept the fact that even with the best intentions we are often navigating a land of guesswork and speculation merely reveal the flaws in their own reasoning process, rational or irrational as it may be.

There are no doubt some who will already hang up the phone on this conversation without further engagement, heading off to rant in another Facebook forum. So be it. My own inclinations fall toward much of the new school of herpetoculture and husbandry thought. I try to look at the testable science first and always, and give that the greatest weight in my decisions. I also look at the experience of longtime firsthand experts. I consider my own firsthand experience as well, including in such subjective matters as trying to read a snake’s internal state. And then I try to bring rational inquiry and critical thinking to all the available information, eventually drawing conclusions and making judgments that, quite consciously and deliberately, remain subject to change. It is a fundamental tenet of the scientific method that all scientific conclusions are provisional.

Without trying to belabor the point, I provide these details of my thought process for the record, for this is how I reach the conclusions and recommendations that I both use myself and provide as a public resource here on this website. Your mileage may differ, but I hope I have made my intentions, and my process, clear.

***

And so now as to the specifics of heating, we can begin with some statements of what we are certain about. Indigos do not tolerate high temperatures, and excessive heat can rapidly lead to death. These aren’t corn snakes or ball pythons, and you must pay close attention to the risks of overheating.

Although we certainly should not accept the Association of Zoos and Aquariums (AZA) manual as the last word on specialty species like Indigos, nevertheless it is worth considering their guidelines in the AZA Indigo Snake Care Manual:

Temperature: Indoor ambient temperatures for Drymarchon couperi should approximate 26.6°C (80°F) during the day and may be allowed to drop slightly during the night. Some D. couperi breeders (Albury, 2001) recommend a thermal gradient of 23-28°C (74-82°F) with lower nighttime temperatures of 18°C (65°F) during winter periods.

These are sound guidelines and keepers are wise to closely adhere to them. The AZA guide continues:

Secondary heat sources (commonly low wattage light bulbs) are only necessary for basking gravid females to offer a thermal gradient. Hot spots for D. couperi should not reach over 35°C (95°F) and should always be evaluated with a thermometer or temperature gun. Testing should be done prior to introducing the snake to the cage to ensure heat parameters are stabilized. The heat source should be located at one end of the cage and the hide box and water bowl at the opposite end to create as much of a thermal gradient as possible. Heat sources should be placed on timers for 8 hours of mid-day exposure in the summer, and reduced to 6 hours during the winter. Hot spots may be eliminated during the winter cycle to achieve winter target temperatures (Kevin Murphy, pers. comm)

Well, let’s unpack that a bit. The recommendation to provide basking heat for gravid females is consistent with observation in the wild. Scientists tracking Indigos in the wild report that basking females become significantly common sights in the gravid season.

However, once we begin to address the notion of basking heat and light, the subject gets complicated and the discussion sometimes, well … heated.

In short, the commonplace claim that many snake species do not bask is increasingly being debunked by observation in the wild. Similarly, the notion that terrestrial species do not climb is increasingly found to be in contradiction with studies in the wild. The rational and increasingly recommended solution to the basking issue is part and parcel of the so-called “light and shade” approach to heating and lighting. In essence this means leaving one end of the enclosure at cooler temperatures and shaded lighting, and concentrating lighting and heating at the other end, including UVB illumination, infrared spectrum lighting/heating source, and optionally daylight lighting for the fullest spectrum that most closely replicates natural sunlight.

A good summary of the light and shade method can be found here: Complete Guide to Heating.

“The light and Shade method allows us, as keepers, to provide a wild-like quantity or index of UV energy over a basking zone in captivity. This zone is then aligned with an equal or greater area of shade. We must seek to provide illumination that is UV- and IR-rich over the entire animal—at least nose-to-vent and across the width (snakes can be illuminated when coiled as long as the projection of light covers the area of mass). The area of provision can be either horizontal across an enclosure or vertical from top to bottom. What we seek to do is provide a ‘per-species,’ ‘wild-like’ basking zone with access to the correct index at the basking point and reducing in power as the animal move away over the horizontal and vertical enclosure space. Full-spectrum light and heat must be provided close together over this basking zone, and should not be split as UV at one end and heat a the other. We must allow our animals to find energy in a natural way and in a way that is most natural to them. We do not have two suns—one for heat and one for visible and Ultra Violet light—and so neither should we have in captivity.” — The Sun: Its Use & Replication within Reptile Keeping by John Courteney-Smith

With regard specifically to heating, there are a large variety of approaches available to provide heating. However, some solutions are far more desirable than others. While it is beyond the scope of this resource to fully explain all available options, more detailed resources about heating and lighting can be found on the Resources page of the website. But here are some succinct takes and summary conclusions.

There is a difference between merely heating the ambient air temperature as opposed to providing heat in a form that penetrates beyond the surface of a reptile’s outer skin and provides deeper heating that reptiles can utilize for greater health benefits, including the ability to warm themselves more quickly and thoroughly. Within the spectrum of infrared radiation there are three gradients, dubbed IR-A, IR-B, and IR-C, also known as near infrared (NIR), medium infrared and far infrared respectively. UVC falls into this range that is not penetrative of the reptile dermis, and this UVC range is what Radiant Heat Panels and Ceramic Heat Emitters provide. Hence these devices should only be used, if at all, for assistance in providing ambient temperature, typically for nighttime heat when required for certain species or in certain climates (i.e. if your home falls to temperatures below the desired nighttime range), providing heat equivalent of natural nighttime heat after the sun goes down and UV-A and UV-B are absent. But RHPs and CHEs should not be relied upon as a primary source of quality heat.

Halogen bulbs provide short wavelength infrared, i.e. near infrared or UVA, which provides the kind of healthy, penetrating heat and light that assists in overall health and metabolism, along with digestion and a long inventory of other health benefits. While halogen lights are considered filament incandescent bulbs that are now outlawed in some states, some of these states still permit their use in bulbs designed for specialty use such as reptile lighting; also, these bulbs can still readily be obtained online from multiple eBay sources. Other alternatives at this end of the heat and light spectrum include Mercury Vapor bulbs.

Unfortunately there is no single silver bullet bulb or device that provides a simple plug-and-play solution to providing proper heating and lighting for reptiles in general and Indigo Snakes in particular. I encourage keepers to delve more deeply into the science and technology of both heating and lighting, taking advantage of the currently available wealth of information about these subjects in the literature and on YouTube. While I do provide a number of recommended sources on the Resources page, as one starting point among countless possibilities I recommend this quite succinct but thorough article by the doyenne of reptile lighting and heating, Dr. Francis Baines, in Reptile Magazine: Reptile Lighting Information.

THERMOSTATS

Continuing to discuss the technology of lighting and heating, you must—absolutely must—utilize these heating devices in concert with a reliable programmable thermostat. Halogen bulbs, mercury vapor lamps, deep heat projectors, ceramic heat emitters, heat radiator panels, under tank heating pads, and under enclosure heating tape are all capable of producing dangerously high temperatures that, in case of a mistake, technical failure, change of your reptile rooms ambient temperature due to weather or equipment failure, etcetera, can suddenly lead to the rapid death of your animals. Do not take chances with heat and the lives of your reptiles!

I recommend (without compensation or benefit) the use of the Herpstat line of digitally programmable thermostats made by Spyder Robotics. These are the priciest versions of digital thermostats on the market, but they are only slightly more expensive than their closest competitor, Vivarium Electronics, and I believe the features of the Herpstats to be far more robust. While the VE thermostats are a bit easier to program, they do not offer the range of features to match the Herpstats, as any quick comparison will demonstrate. First and foremost, currently only two models of the VE thermostats (the VE-200 and VE-300) offer “dimming” (proportional) function, which enables these thermostats to be used to control incandescent bulbs, i.e., halogen lamps, DHPs, and most kinds of basking lamps. This dimming or proportional functionality provides a constant flow of electricity to the heating element until the desired temperature is met. It is the most accurate and consistent form of heating control.

Inexpensive on/off thermostats can be used with CHEs and heat mats, but this is a primitive type of control that will not provide precise results; it’s best to assume they will provide accuracy no better than within five degrees. The result of this is that your enclosure’s temperature may constantly be readjusting, varying up and down within a five-degree range or thereabouts. This is, for example, entirely unacceptable for incubating eggs.

Pulse Proportional thermostats are preferable for use with CHEs, UTHs, and heat tape; basically with any sort of heating element that provides contact heat and that does not emit light. However most of these heat elements can also be used with dimming thermostats, with the exception of fluorescent lighting, mercury vapor lights, or anything that requires a ballast.

While the Herpstat thermostats are frankly a bit more difficult to get the hang of programming at first, once you gain familiarity than usage becomes a simple matter. The Herpstat thermostats also provide two outlet and four outlet models, which I find extremely convenient. Until the recent release of the upgraded Herpstat 4, I used a Herpstat for each of several enclosures, using one outlet for heating (via thermostat) and one outlet for UVB lighting (programming it as a timer).

In addition to these and many other features, the Herpstat 2 and the Herpstat 4 also offer a WiFi function, so that you can program the unit through a phone, tablet, or computer, which is far more handy than using the multi-function buttons of the unit itself (which are similar to programming any computer device that has very few buttons but very many programmable functions; think Casio wristwatch!). Along with this feature, these two models can also be programmed to send scheduled emails providing the status of the unit and its readings, i.e., the actual temperature of the enclosure, any failures, alarms or automated resets, and so forth. Although use of this feature is optional, I like having it very much, especially when I am traveling and I can be notified of anything unusual that I can immediately phone home about and check on.

There are many other less expensive thermostats on the market. I will state here what a specialty reptile shop owner friend told me that he uses as his personal guideline: If a thermostat costs less than $100, don’t trust it, and don’t buy it. Your mileage may vary, but violate this recommendation at your own risk.

In fairness I should mention that if you happen to be using a simple UTH to provide some supplementary heating in addition to other primary heat or lighting sources, you could buy in inexpensive home light dimmer switch to control a UTH. The dimmer is not a thermostat and will not provide any temperature information or control; however, if you carefully monitor the device and the tank for a period of time, using an accurate infrared thermometer (and not just a stick-on or wired ambient temperature thermometer), you can with some experimentation determine a single safe setting for the dimmer and UTH, that you will not further alter or adjust. You must determine this setting reliably before leaving it permanently in place and before introducing any animals to the enclosure! This is not an ideal technology but it can be utilized in some instances so I have included it here. For this and indeed any thermostat or heat-controlling device, you must be certain that the dimmer or thermostat is rated for the wattage commensurate with your heat source. On/off thermostats are typically rated in the low hundreds of watts, and home dimmers can be even less, intended for merely a small desk lamp, so double-check that you don’t risk burning out the dimmer or thermostat. Higher quality pulse and dimming thermostats can commonly be rated for 400W, 600W, and 700W.

USE OF HALOGEN BULBS WITH DIMMING THERMOSTAT

Regarding the use of halogen bulbs along with dimming thermostats, II.com reader Quentin Dishman offers the following succinct explanation:

“Dimming a halogen or other broadly incandescent bulb necessarily changes the tungsten filament’s temperature, which in turn alters both the total output (in W/m^2) and the spectral proportions.

For example, dimming a halogen bulb of given wattage X reduces the total irradiance by about a third. At the same time, the proportion of IR-A decreases even further, to about 60% of the undimmed amount of IR-A. A halogen bulb with a wattage of 0.9X would—at full power—actually provide 50% more IR-A than the dimmed bulb of slightly higher rated wattage in W/m^2.

Therefore, in the interest of maximizing sun-like NIR and IR-A in particular bulbs should generally be chosen such that no dimming is ordinarily required. In effect this also turns the thermostat into a secondary safety device, dimming the bulb only when the baseline room temperature is abnormally high.

Echoing the AZA’s mention of “low wattage bulbs”, Francis Cosquieri—a UK-based rat snake specialist—often uses an array of several 20-35W halogen bulbs for his larger colubrids, as this is a wattage that, in his situation, enables them to run at full power, producing the largest amount of sunlike NIR.” [My thanks to Quentin Dishman for these suggested additions.]

SENSOR PROBE PLACEMENT & THERMOSTAT PROGRAMMING

Frances Baines and Roman Muryn emphasize that probes can only measure themselves. For the same reason that weather stations place their thermometers in Stevenson cages, probes can only measure air temperatures accurately when in the shade, where the probe is physically in a state of equilibrium. With well-chosen bulbs, this effectively allows the thermostat probe to be placed in the shade as well, only dimming the bulb when the air temperature exceeds a given threshold. This is somewhat more reliable than using a probe exposed to direct visible and NIR radiation, as a probe’s physical absorption and emissivity properties are not necessarily useful to us.

Figuring out where to locate the temperature sensors can be a challenging puzzle. If you scroll down on this husbandry web page you will see a diagrammed photo of a 48” PVC enclosure that illustrates much of the best practices discussed here. Here are the nitty-gritty details regarding programming and sensor placement. Give this some time and thought until it makes sense, as it can be a bit hard to follow at first.

On one Herpstat 2 thermostat I program Sensor 1 for daytime basking temperature, connected to the Halogen basking spotlight. The basking location is a dark colored large stone used in building garden structures (you can find such stones at Lowes and Home Depot). Using a 1/2” masonry bit I drilled a channel from one edge of the stone to the very center. The sensor is threaded into this channel so that it rests within the stone at its center.

The halogen lamp programmed to to that sensor is set for a higher temperature than the ambient temperature that is safe for the enclosure. That is to say, I am trying to hit about 81 or 82 degrees as daytime temperature in the enclosure, but I set the thermostat for 88 degrees; if the sensor within the stone reaches that temperature it means that the basking surface will probably be at 90 degrees or thereabouts. The alarm is thus set at 88 because the sensor within the stone will not typically reach this. HOWEVER the important key here is to test and refine the system by using the IR temp gun to frequently read the temperature on the surface of the basking stone; at the same time, watch the ambient temperature sensor, which will show on the second sensor reading, to know the ambient temperature of the enclosure. This way you have sufficient information to know that the halogen setting is (a) keeping the enclosure at 81/82 degrees overall, while (b) keeping the basking surface to about 88/90 degrees. The thermostat temperature (for the sensor within the stone) is therefore set to 88 degrees, because I have learned through these testing procedures that this is the setting that will deliver both the desired enclosure temperature and the desired basking temperature.

Meanwhile, the second sensor, which is connected to the LHP bulb for nighttime ambient heat, is buried about an inch down in the substrate at about the center of the enclosure; it is near but not directly beneath the DHP, which is located several inches rightward from the center of the enclosure. Looking at the readout for this sensor will tell you the ambient temperature of the cage, which would be inaccurate if you position it close to the heating elements or the basking zone. However, the thermostat is programmed at 78 degrees for this sensor, which is the desired nighttime temperature.

For timing, this sensor and the LHP bulb need only be set in only a single constant setting, 24 hours per day. Why? Because during the day, when the halogen bulb raises the temperature above this limit, the LHP will not go on because it’s not needed. Only at night, when the halogen shuts off, will the LHP come on if and when the enclosure falls below 78 degrees. Otherwise, it remains inactive. This clever approach is the idea of Francis Baines. (Although it is unnecessary, I choose to program the LHP for 12 hours, simply to help me to keep tight track of the somewhat complex dawn/dusk lighting and heating I maintain, which is explained further under BEST PRACTICES.)

Note that both heating bulbs are set to “dimming” rather than “pulse” in the thermostat settings. Note also that while the second sensor setting of 78 degrees is in a constant mode, the first sensor tied to the halogen bulb is set for a 10-hour window, from 8:00 am to 6:00 pm. (When breeding Indigos you will want to shorten their “day” light and heat in the fall, to more closely mimic their native environment.)

Finally, the “ramping” feature is engaged with both settings, so that the temperature, and the light produced by either bulb but particularly the halogen, will gradually come on or fade off, somewhat mimicking dawn and dusk, rather than abruptly turning on or off. The ramping time is set two hours before the timing window of the UVB and daylight spectrum fluorescent lights (discussed in the next segment).

UVB LIGHTING

“… I am convinced that natural cycles of light, infrared and UV (i.e. "sunlight") are vital for health, fertility and embryo development for almost all species.”

— Dr. Francis Baines

As we transition from heating to lighting (and the two are closely related in form and function), we need to address UVB lighting, which provides the critically necessary ultraviolet spectrum for the vitamin D3 cycle among other metabolic purposes. Determining the amount of UVB—that is, the power, length, and strength of UV radiation—is not entirely simple to do, but is also not exceptionally complicated with a bit of education about the contributing elements.

Recent advances in UVB bulb technology have actually made the process of determining needs and solutions simpler, if not yet entirely easy. Various UVB bulbs are now available which range in strength of UVB radiation, measure in percentage of the lighting spectrum the bulb provides (and these bulbs also include the necessary UVA spectrum as well). UV radiation also varies rapidly depending on the distance from the animal, to the point that in determining the proper bulb mounted at the appropriate height, we need to take into account the difference between the amount of UVB that reaches the surface of the substrate, to the amount of UVB that reaches the highest point of the basking zone (such as a raised stone or a stone atop a hide), where the UV will be more intense. That variation is useful to offer as it will assist the animal in regulating its own exposure, but the maximum area will need to be carefully considered so as not to present too intense a level that can be come dangerous to the animal.

In 2010, Gary Ferguson (et al) published a landmark paper describing “Studies of voluntary exposure to ultraviolet-B (UVB) radiation from the sun in the field … conducted in the southern US and Jamaica for 15 species of lizards and snakes occupying various habitats. Species were sorted into four zones of UVB exposure ranging from a median UV index of 0.35 for zone 1 to 3.1 for zone 4.” As a result of that paper, the four zones of UVB exposure became known as Ferguson Zones. (You can find the original paper on the Resources page.) What all this means however is that different species that hail from different climates require different ranges of UV radiation, reflecting their natural habitats.

Building on Ferguson’s original work, in 2016, Francis Baines (et al), a collaborator on the original Ferguson paper, published “How much UV-B does my reptile need? The UV-Tool, a guide to the selection of UV lighting for reptiles and amphibians in captivity,” which elaborated significantly on the foundation of Ferguson’s 15 species, expanding the list to include UVB guidelines (using Ferguson Zones) for 254 species, accompanied by “… test reports and UV-index gradient maps for commercially available UV-B lighting products, and a guide to selection of appropriate lamps for use in vivaria and in larger zoo enclosures.” (You can find this paper and the UV-Tool linked on the Resources page.)

Thus desert species require higher levels of UV than forest spaces that are exposed to less direct sunlight in the wild. These needs are reflected in lower Ferguson Zones for the shade-accustomed species, and higher for species accustomed to being exposed to more intense sun and heat.

The Ferguson Zone concept, and subsequent research that has greatly expanded the list of referenced species, combined with advances in bulb and lamp technology, represent inordinate changes in how we think about and are capable of keeping captive reptiles. But it is still early, and no one would claim that this research and guidance is absolutely certain and precise, nor is it the final word. It really represents a starting point, and a safe set of recommendations, with some basic equipment to utilize in service to the latest data available. But it is quite possible that many of the Ferguson Zone limits are too conservative (see my note in (18) Best Practices regarding Todd Goode’s thoughts); and it is also certain that better lighting technology will be developed, that will eventually safely provide full spectrum lighting without using three or four devices, and that will not produce as much unwanted heat. But for the time being, this is the guidance we have, and it is our responsibility as caretakers of our animals to make the very best efforts we can to provide the very best conditions for their health and well-being.

With that brief background information (and related caveats) as context, colubrid snakes in general and Indigo Snakes in particular are recommended to be safely kept with UV lighting that falls in a range from Ferguson Zone 1 to Zone 2. Although Indigos come from the southeast United States where their daytime conditions can reach significant light and heat, Indigos tend to generally avoid the intensity of direct sunlight during the highest midday heat periods. They avoid this by using brush and ground cover as partial shielding from the sun, and can also dig and tunnel through such cover when it is sufficiently loose to be able to nose their way in. For greater coolness and temperature stability they adopt abandoned gopher tortoise dens and tunnels, in which they routinely sleep, and also use as dens to lay and incubate eggs. These dens and tunnels can run as deep as 20 feet and as long as 40 feet underground. The life cycle and survival of the Indigo Snake is thus intimately intertwined with the gopher tortoise; as goes the survival of tortoises, goes the survival of Indigos.

There are guides provided by the manufacturers of UVB lamps, as well as in the literature of herpetoculture, as to what type of bulb to use in order to achieve the desired Ferguson Zone of UVB radiation at the heights available within your enclosures. The leading manufacturers of these lamps are currently Arcadia and ZooMed, and the data and charts they provide for their bulbs is presented in somewhat different ways and can be confusing at first. Seek assistance not only from researching the literature and instructional video, but also from your local specialty reptile shop. Arcadia makes an array of UVB bulbs that range in the percentages of UVB provided, including their Dragon Lamp, Desert Lamp, Forest Lamp, Shadedweller Lamp, and also their Natural Daylight Lamp for daylight spectrum as well as the Jungle Dawn LED strip for the same purpose. ZooMed’s Reptisun bulbs include the NatureSun or ReptiSun fluorescent lamps. Both Arcadia and ZooMed provide various kinds of guides and other information on their respective websites. ZooMed focuses on particular species and while this might simplify matters if you are keeping one of those named species, it does not provide as much depth and context as Arcadias reference and guidance resources in my opinion. Your mileage may vary, and these links will lead you to the respective online guides:

Arcadia UV Index Lighting Guide

ZooMed Lighting Selection Guide

UVB bulbs are notorious for deteriorating with age. Typically UVB bulbs are considered unlikely to last beyond one year, and UVB output will often significantly diminish months ahead of that. However, many users result much longer usable life than this, and the deterioration rates and degrees are gradual, hence for example a somewhat deteriorated bulb can still be perfectly usable if you raise the basking area higher off the substrate surface and closer to the aging bulb. There is no way to determine this change visually however, as the bulbs will continue to produce visible light for a very long time, and can safely be used purely for that purpose. But at very least, keep track of your usage and replace bulbs in a timely fashion. For what it is worth, there appears to be greater confidence in the quality and consistency of the Arcadia bulbs, and these are what I use. (I receive no benefit from this or any other endorsement.)

However, while we can attempt to make best estimates based on manufacturer’s charting of UVB percentage, predicted readings at various distances from light source to the head of the animal at various levels in the enclosure, and the age and quality of bulbs … the real truth of the matter is that the best solution to eliminate the guesswork regarding UVB lighting is to buy a quality meter that precisely measures UVB radiation. Fortunately today we have a notably reliable unit, namely the Solarmeter Model 6.5R Reptile UV Index Meter. While this item is not inexpensive, it is an invaluable tool. This meter lists for $249, however it can sometimes be found on sale for $225 or even at $194 on occasion. I highly encourage its purchase for anyone who keeps reptiles and plans to utilize UVB lighting. Quite simply, many authorities, and I agree, consider the Solarmeter a requirement for successful and effective use of UVB when keeping reptiles. And in the long run it will save you money, because you can closely monitor the output of your bulbs and only replace them when actually necessary, eliminating any guesswork.

Note that Solarmeter tries to encourage customers to also purchase the Model 6.2R “Lamp Meter,” claiming: “Model 6.2R Reptile UVB Lamp Meter is ideally suited to determine if UVB lamps are performing to manufacturer’s specifications, gauge their intensity, and measure their aging over time.” Do not be confused; any difference between these two meters is not sufficiently different to warrant its purchase. You can detect changes in the aging of UVB bulbs with the 6.5R.

Note also that the Model 6.5 is dubbed the “UV Index Meter,” but the technology of this meter is not specially designed for measuring Ferguson Zones for reptile lighting, other than the fact that Solarmeter applies a label to the face of the meter, which serves as a handy reference point. And that similarly, if you see other companies offering a UVB meter for similar price and appearance, it is likely just a Solarmeter 6.5 to which that firm has been permitted to apply their own branded label.

One important note of perspective before moving on to complete the lighting spectrum. Todd Cooke of LightYourReptiles.com (you can find their contact info in the SOURCES section here on the Husbandry page), who has been involved with reptiles and marine aquaria as long as I have (that is, since the 1970s), points out that the Ferguson Zone concept should not be regarded as the final word on lighting guidance. He observes that it is difficult to distinguish, on the basis of basking behavior in the wild, whether an animal is seeking UV radiation, or simply seeking IRA/IRB belly heat from a warm surface, and poses the question of how would we distinguish between these intentions or needs? Hence Todd proposes that the ideal lighting and heating array in captive enclosures should be spread over three or even four distinct zones when possible: That is, heating separate from UVB separate from daylight separate from cool shade. The key justification here is that in this way an animal is afforded the opportunity to simply warm itself without being forced to absorb UV at the same time — and vice versa. Of course, this becomes challenging in smaller enclosures, as for sizable animals like Indigo Snakes, if you were to spread out the lighting/heating array in this fashion, it would be difficult to achieve a shaded/cool zone in anything less than an eight or ten foot-long enclosure. In a four-foot enclosure for sub-adults, I therefore follow conventional wisdom of tightly aligning the light and warm side of the enclosure, in order to achieve a detectable differential for the cooler shade end of the enclosure. However, with smaller animals such as geckos, you could certainly follow Todd’s suggestions and spread out the enclosure into three or even four zones.

I think the important message to be drawn from Todd’s thoughtful comments is that while the current Ferguson Zone guidance is a significant step in the progress of captive reptile husbandry, it should by no means be regarded as the end all of our thinking about UV lighting when considered in the context of trying to integrate IR, daylight, and heating requirements. We have not begun to determine requirements of thousands of reptile species, and there is a significant difference between observing wild behavior and captive behavior and needs. As I have pointed out elsewhere, while we should make every attempt to explore and utilize the very latest scientific data, when attempting to provide the very best captive husbandry, we are still very much in the land of educated guesswork, and anyone who thinks they possess knowledge of the One True Way should take a breath before jumping on line and judging what others are doing as wrong or egregious, simply because it may be somewhat outside the prescribed norm, and especially if it is motivated by a thoughtful and informed approach.

DAYLIGHT SPECTRUM & REPLICATING THE SUN

One additional lighting feature that can be added to this kind of setup is something that provides stronger daylight spectrum, as the rest of the lighting array is not particularly bright, and will also leave the cooler end of the enclosure in relative darkness. This is not merely an aesthetic choice, but rather in the attempt to most closely replicate sunlight conditions within an enclosure, more intense daylight spectrum lighting will bring the environment closer such attempted duplication. Since daylight spectrum provides little or no UVB, depending on the precise source used, it can also be used, if you wish, to extend into the cooler “shade” area to provide attractive overall illumination in the enclosure. Two high quality options to completing the daylight spectrum and adding daylight lighting intensity are the Arcadia Natural Sunlight Lamp versus, or the Arcadia Jungle Dawn LED bar (for which there are other less expensive options available in the marketplace, albeit that likely do not provide the same intensity of light). The Natural Sunlight Lamp, a fluorescent bulb, offers superior spectrum range, including 2% UVB. However you may not wish to add any additional UVB to your enclosure if you have established the desired level entirely with your existing UVB lighting. The Jungle Dawn will provide much higher degree of luminescence, but perhaps surprisingly it will also add more heat to the enclosure because the visible light range it provides is in itself a potent energy source. Also, the LED strip’s beam is highly directional, hence it will warm surfaces directly in its path below. The bottom line in choosing between the two would be that if you want to add very bright daylight, use the LED strip, but confine its range to the basking zone so that its heat is contained therein. Whereas if you are liking to provide a softer lighting across a wider range of the enclosure including part or all of the cooler shaded end, then choose the Natural Sunlight fluorescent.

PROTECTIVE LIGHTING GUARDS Finally, all of these heating and lighting elements get quite hot—the heating bulbs get very hot themselves, the metal fixture parts for the fluorescent and LED fixtures get quite hot as well, easily in excess of 100 degree Fahrenheit. Hence all heating ad lighting fixtures should be contained in protective guards or mesh “cages.” Circular models are readily available for incandescent fixtures. And Arcadia makes the LampGuardPro for enclosing fluorescent fixtures. These accessories are must-have equipment in order to prevent your snake from burning itself when exploring the enclosure and various fixtures, as they are prone to do.

Note that the mesh guard will reduce the fluorescent radiation by approximately 15%, so you must take this into consideration when planning for your desired UVB Ferguson Zone level. On the other hand, if your UVB is too high, you can add some additional mesh in the guard to further reduce some of the radiation.

***

A Single Solar Source

“The sun projects all of the terrestrial wavelengths of light from UV-B to infra-Red-B into our world. This is a single source of energy, supplying us with heat, visible light and UV. It is therefore important that we do not split up heat and light sources within captivity. All heat and light sources should be grouped very closely alongside one another in order for an animal to utilize this energy naturally, self-regulating its own exposure as it has need. Zoning is vital to the correct supply of re-created terrestrial light. This will allow an animal to “self-select” or “self-regulate” its own level of exposure within its own biological cycles, from controlled heat and full-spectrum light to cool and shade, just as it would in the wild. Placing a heater at one end of an enclosure and a lighting system at the opposite end is non-natural, and will therefore not allow the animal to thermo-regulate or photo-regulate properly. This leads to zonal irregularities and incomplete or under-provided for biological cycles. The animal will not be able to lead a natural life and could go on to experience further and avoidable disease.’” — The Sun: Its Use & Replication within Reptile Keeping by John Courteney-Smith

INFRARED GUN

Etekcity Infrared Thermometer Temp Gun

Hand-in-hand with heating and thermostats, another absolutely required tool is an infrared thermometer gun, as also commonly used for cooking, pizza stones, grills, and so forth. A good quality IR gun can be readily had for about $30. This is an invaluable tool for accurately determining temperature at various surface locations within the enclosure. Temperature sensors that are attached to programmable thermostats or other digital thermometer devices can be challenging to utilize accurately, depending on placement location of the sensor. The infrared gun provides an accurate surface temperature that reliably informs you as to what the actual results of your thermostat settings and heating and lighting elements are producing.

PROGRAMMABLE OUTLETS Lighting elements such as UVB and daylight lighting are typically run from timers rather than temperature controlling thermostats. An inexpensive way to provide timing control of these elements of your lighting is the use of either digital or analogy mechanical timers. Either can be used to turn lights on during the day and off at night. Analog electromechanical light timers (aka terrarium controllers) are an old technology that, while reliable, can be annoying to program. Digital power outlets are technically more sophisticated but also often frustratingly arcane to program. However in either case, once the trick is mastered, these devices can inexpensively serve the purpose of controlling daytime lighting. There are many analog timers available within the pet trade. For digital versions, you might want to consider the BK-Link BN-LINK 7 Day Heavy Duty Digital Programmable Timer Outlet, which is available in single outlet and dual outlet versions. I find them extremely economical and handy, sparing some of the inputs on my Herpstat thermostats for use with heating elements rather than pure lighting devices.

SNAKE HOOKS & MORE

A lightweight, 18” hook is ideal for juvenile Indigos and will likely serve until they reach about 48”, at which point you may want to go to 24” and a bit heavier, but not too heavy—there is no reason to risk injuring your snakes accidentally, so I prefer hooks made of synthetic materials rather than metal. The hook is a tool and it is worth watching experts using it—including with venomous species—to learn how to properly “tail” a snake, while getting it to “ride” the hook with front quarter to a third of its body.

HUSBRANDRY.PRO

While there are a number of reptile husbandry software apps available (that I do not have firsthand experience with), I am a big fan of HUSBANDRY.PRO: professional reptile tracking software for your personal or commercial collection. It is incredibly inexpensive — free for up to five animals, $4 a month for up to 50 animals, $9 for up to 200 animals, etc. But the features are extensive and hugely functional. It also syncs across devices, so I can log in, or make entries, from anywhere, including my phone, tablet, or computers. I keep track of all feedings, sheds, weights, feeder inventory and costs, and more. There is lots of ways to configure or look at the data and you can readily see growth charts for example that quickly tell you how each animal is progressing. For breeders you can keep track of genealogy, pairings, and also generate QR codes to keep track of enclosures with significant quantities of hatchlings. I find it invaluable even for a small collection because I’m never wondering what or when I last fed, or when a particular animal last shed. Like I say, it’s free for 5 animals or more, so give it a try and see what you think.

VIDEO CAMERAS

Recently I have installed a Wyze Pancam V3 video cam in a PVC enclosure. It’s easy, inexpensive, and fun, providing live camera feed (including excellent night vision) to my phone via the Wyze app. This is a remote controlled PTZ (pan-tilt-zoom) camera, and with an SD memory card you can save recordings and photos, and you can also set the camera to record when it detects movement. Useful and fun technology!

MORE

There is no shortage of miscellaneous accessories and tools that can come in handy when keeping snakes. Hides, for example, come in a variety of shapes and sizes, and differ from humid hides, whether commercially manufactured or homemade. These are subjects I may expand these materials to include in the future.

HEATING AND LIGHTING SCREEN TOPPED ENCLOSURES

Up until now I have assumed the use of a PVC enclosure or similar enclosure of wood or fiberglass, in which case all of the heating and lighting elements would typically be mounted within the enclosure, suspended from beneath the top or ceiling surface (hence the need for protective guards). However, it’s possible that you might be using some sort of screen-topped enclosure such as a glass aquarium. I don’t particularly recommend these, as all that screening makes it difficult to retain humidity as well as heat, and also provides a dangerous possibility of escape-inclined animals injuring themselves by rubbing their noses against the screening (or other animals like lizards and tarantulas potentially damaging feet and claws by hanging from the screen).

However, if you are using such an enclosure, perhaps for younger snakes until they are large enough for your investing in PVC or similar large enclosures, note that you will not be mounting any of the lighting or heading elements beneath the screen, but rather sitting atop the screen. For this, the incandescent fixtures will require dome reflectors, and the fluorescent lamps will be used in reflectors that can safely sit atop the screen. As with internally mounted heating and lighting, the array should be concentrated at one end, over a basking area, with the other end allowing for a shady area and cooler temperature.

PLASTIC TUBS

I have discussed the use of plastic tubs in section (9) Enclosures. While I do not approve of tubs as permanent homes for adult snakes, we home keepers may require the use of tubs for juvenile animals, until they reach sufficient size that we are able to house them in more substantial enclosures.

With tubs, it is not practical to provide overhead heating. It is conceivable that one can cut out areas of the plastic cover and cement into place wire screening, above which incandescent heating elements could be placed. I may yet experiment with this in the future but as yet I have not done so. Hence for heating purposes I provide admittedly inferior belly heat via the use of heat tape, a remarkable if simple technology that we did not have when I was first in the hobby and industry several decades ago. That said, we generally used conventional incandescent lighting fixtures as a heat source, and so without any full understanding of the implications, we were at least providing some minimal UVB and IR radiation, albeit far from enough, but far better than relying entirely on heat mats or other contact heating sources beneath the enclosure.

Heat tape is readily obtainable from specialty reptile equipment suppliers. Be careful to make certain whether or not you are purchasing wired or unwired heat tape. In the latter case you will also have to purchase wiring and attachment hardware, and learn how to assemble these parts. It is far easier for home hobbyists with small collections to simply purchase wired heat tape, which comes in various widths, and can be ordered to varying lengths and then subsequently easily cut to adjust its length (but not its width).

Some veteran Indigo Snake breeders recommend covering the entire bottom surface of the tub area with heat tape, and have had longtime success maintaining constant temperatures without heat gradients. That said, current conventional wisdom prescribes the importance of providing a heat gradient (as in the light and shad method when heating and lighting from above), thus I choose to cover about one third to a half of the tub’s bottom surface area with appropriately sized heat tape, leaving the balance of the enclosure’s bottom bare and therefore somewhat cooler. This serves to provide a hot end and a cool end of the tub, so that the snakes can control their own thermoregulation. I set the thermostat’s wired temperature sensor in the warm hide that resides over the heat tape area of the tub, and provide a water dish in the opposite, cool end of the tub.

While this system does not provide overhead incandescent heating or lighting, contrary to popular belief, you can and absolutely should provide UVB light suspended above the tub. (You cannot safely set these reflectors directly onto the plastic lid due to the risk of melting the plastic and potential fire hazard.)

While it is widely known that glass and certain acrylics will filter out UV radiation, blocking the UV spectrum from penetrating through a glass or plastic cover, in fact, UV will penetrate polystyrene tubs and lids, albeit some percentage will be filtered out. On the Resources page I provide a brief report of my own basic experiments and testing in this area, but suffice it to say that the containers I use (manufactured by Sterilite and readily available from retail chains like Target and Walmart) filter out a range of UVI from 33% to 50% depending on the distance of the bulb from the plastic. With sufficient experimentation using a Solarmeter and controlling for distance and choice of bulb intensity, one can readily control the UVI that reaches the surface of the substrate and or basking area (for example, the top of the hide) to the precise desired Ferguson Zone range. I do this with all my tubs and readjust accordingly as snakes are gradually shifted through progressively larger tubs.

These arrangements are not ideal but if combined with sufficient enrichment—some branches for climbing, pieces of cork bark for exploring, a variety of foods, introduced items of varied interest and exploration such as the occasional cardboard paper towel tool or widely perforated rubber dog toy, along with regular handling and exercise outside of the enclosure—you can raise animals that are both physically and mentally healthy and stimulated, until such time you can move them to larger enclosures with ideally equipped lighting, heating, basking and hiding features.

See the concluding guidance for tubs and screen tops in section 18 on Best Practices.

This is a useful list of suppliers that I have personally had good success with. It is by no means intended to be complete. These are not blanket endorsements and I receive no benefit with the exceptional case of an affiliate link, in which case if you make a purchase via the referral link I receive a small return that does not add to your cost; however that is not the purpose of this list.

Reptile Basics www.reptilebasics.com

Phone: (336) 308-5767

inquiry@reptilebasics.com

Large varied catalog. I have purchased Connected Heat Tape and Non-Locking Hemostats from them among other items. They also carry the Solarmeter 6.5R Reptile UVB Lamp Meter.

Reptile Supply Co., Inc. www.reptilesupplyco.com

Lugarti Ultralight Matte Black 18" Snake Hook (Also comes in other colors)

1425 Old Ector Rd Bonham, TX 75418

916-226-4089

info@reptilesupplyco.com

Large varied catalog. I have purchased Spyder Robotics Herpstat thermostats from this supplier. They carry the Lugarti reptile product line including a Lugarti Ultralight Matte Black 18" Snake Hook that I like. They also carry the Solarmeter 6.5R Reptile UVB Lamp Meter.

Spyder Robotics www.spyderrobotics.com

sales@spyderrobotics.com

This is the manufacturer of the Herpstat thermostats and they sell directly as well as distribute to other outlets. I have had good experiences with their support.

Venom Life Gear www.venomlifegear.com

407-312-9290

Info@vlg.email

Good selection of snake hooks. Other than that, they cultivate the venomous keeper market (read: YouTube and Instagram wannabees) and so they sell more branded merch than they do useful gear, to people who probably care more about fashion and web views than reptiles. But they do have some nice hooks.

Midwest Tongs, Inc. www.tongs.com

Rubber-Coated Tweezers

14505 S Harris Rd

Greenwood, MO 64034

(816) 537-4444 Free: (877) 87TONGS

info@tongs.com

Good selection of snake hooks and rubber-tipped tweezers

Dragonhaus, LLC www,thedragonhaus.com

(253) 572-0501

custom@thedragonhaus.com

700 E D St, Tacoma, WA, 98421

Good general catalog. Also make enclosures.

Light Your Reptiles, Inc. www.lightyourreptiles.com

207.588.7210

LightYourReptiles@yahoo.com

Excellent source of lighting information and equipment. Email or call with your questions and you will get attentive and expert answers (and tell Todd I sent you!)

RodentPro.com, LLC www.rodentpro.com

P.O. Box 118 Inglefield, IN 47618

(812) 867-7598 Fax: (812) 867-6058 info@rodentpro.com

I’ve had consistently good experience with RodentPro as a mail order supplier for frozen whole prey food . Equally good reports come from longtime customers of other major suppliers including Layne Labs and Perfect Prey. You might try an initial order from each and compare quality and your experience firsthand, but all three are generally considered reputable, and there are other smaller sources as well.

Reptilinks www.reptilinks.com

Reptilinks LLC of Blanchester, Ohio 720-841-8762

Info@reptilinks.com

Reptilinks makes handmade whole prey “sausages” for reptiles. I use their iguana and frog varieties for my Indigos. All my snakes, once they were well established feeders, took Reptilnks off tongs immediately, and now all take them on their own from a dish.

Rare Genetics, Inc. www.raregeneticsinc.com

Rare Genetics, Inc. P.O. Box 1368 Christiansburg, VA 24068

Reptile Genetics provides inexpensive and reliable genetic testing in order to determine the sex of your snakes from sheds, at $15 per shed. Highly recommended and lets you avoid the risks of “popping” or probing.

Cloud Forest Design www.cloudforest.design

1937 Stonewyck Ave.

Kannapolis, NC 28081 cloudfestdesign@gmail.com

This firm makes very professional looking laminated educational labels and signage for many reptile and tarantula species. They have two options for Eastern Indigos as well as labels for Texas and Mexican Redtail Indigos.

Beast Pets & Supplies https://beastpets

9722 Campo Road

Spring Valley, CA 91977

(619) 944-7001

If you are in the San Diego area we have several quality reptile shops. I highly recommend Beast Pets in Spring Valley (tell Shawn I sent you) but there are also animals, supplies and live and frozen foods to be found at SoCal Scales and Pet Kingdom.

And here is an Amazon link for an

Etekcity Infrared Thermometer Temp Gun

Indigos Snakes are members of the Drymarchon genus, which range from the southeastern and southwestern United States, through Mexico, Central, and parts of South America. All of the snakes in this genus share certain traits, including their manner of hunting, their variability of diet, and to a fair degree, their temperaments. And while this website explicitly celebrates Eastern Indigos, all Drymarchon species are fabulous, beautiful animals that make for terrific captive snake species. I love and appreciate them all, I just happen to love the Eastern Indigo most of all. And keep in mind that all of the husbandry information on this site more or less generally applies to all Drymarchon species.

In effect, the entire Drymarchon genus could generically be referred to as Cribos, and the Eastern Indigo considered the Southeast American Cribo, especially considering that these “common names” are routinely avoided in the scientific community, as the only way to be certain of accuracy when considering individual species is to identify them by their latin nomenclature including genus and species, as in Drymarchon couperi.

While there are several claimed species or subspecies of Drymarchon that have been historically identified by rare sightings or a single individual, such taxonomic arcana is beyond the scope of this website. Suffice for our purposes to mention the six common Drymarchon species:

• Yellowtail Cribo (Drymarchon corais)

• Unicolor Cribo (Drymarchon melanurus unicolor)

• Black-Tailed Cribo (Drymarchon melanurus melanurus)

• Eastern Indigo Snake (Drymarchon couperi)

• Texas Indigo Snake (Drymarchon malanurus erebennus)

• Mexican Red-Tailed Indigo Snake (Drymarchon melanurus rubidus)

D. couperi is the only species listed as threatened and protected by federal law. (Erebennus are protected by state law and cannot be removed or killed within the state.) Wild D. couperi specimens cannot be removed from the wild (or even handled) with the exception of specially permitted scientific research.

The other Drymarchon species listed here can be kept legally and indeed can be collected in the wild. Some wild stock continues to be important among the three Cribo species, but all six of these species are now captive bred and can be legally purchased, generally for somewhat less money than the price of an Eastern Indigo, but there are exceptions as some of these varieties are growing increasingly popular with hobbyists.

As mentioned, husbandry requirements are virtually identical for all six species, albeit that the three Cribo varieties get even larger than Indigos and so require appropriately sized large enclosures.

As to temperament, most Drymarchon are disinclined to bite. That said, however, D. couperi consistently remain the most handleable and tractable species. Other Indigo and Cribo varieties can sometimes be a bit more skittish, not necessarily prone to bite but more high strung, less tolerant of handling, and less likely to remain still in your hands. Handling a restless eight or nine-foot Cribo can be a challenge and requires a somewhat skilled and experienced handler, lest you accidentally induce a frustration bite.

The only breeder I know of who has a long history of consistently breeding all six Drymarchon Species is Black Pearl Reptiles in Southern California.

[Please be sure to scroll down the page to see the best practices annotated photo and diagram!]

As I have already noted: There is no single silver bullet bulb or device that provides a simple plug-and-play for reptile heating and lighting. That said, I can attempt to summarize best practices as follows:

Lighting and heating are best provided from above, not below, the enclosure. (I will further address below-heating devices in a moment.) Using the light and shade approach, align your array of heat and light devices at one end of the enclosure, all of which will combine to provide a basking zone for your animals. While Indigos are not particularly prone to basking, the term does not refer to a narrow area beneath a tightly focused spotlight, but rather a surface that will retain heat and will provide maximum lighting spectrum, as contrasted with a cooler and darker area, so that the animal can choose its own preferences regarding thermoregulation. The basking area should be raised somewhat from the bottommost surface of the substrate, to provide maximum UV radiation when the animal is resting on the basking surface, which should preferably be made of some type of dark stone material (darker stone absorbs more heat).

Above this basking zone you should provide:

• A halogen or similar lamp to provide daytime and basking heating

• A DHP (Deep Heat Projector) lamp for nighttime temperature maintenance, which provides important IR radiation without significant light in the visual spectrum. (As an alternative, a CHE can be used, but this provides no useful radiation other than IRC for temperature, whereas the DHP, when it is on, will provide a more realistic spectrum.)

• A UVB bulb and reflector

The UVB should generally be mounted lengthwise, that is, left to right and toward the front of the unit, with the halogen and DHP lamps mounted next to one another and behind the UVB. This array should be located directly above the basking area, and it is wise to provide a dark stone like slate, or a large cement stone used for constructing stone garden structure, which will best absorb and retain heat. Animals will not only bask beneath the UVB and heat lamps from time to time, but in the evening when the visible light is absent they will often position themselves on the warm rock in order to gain “belly” heat, particularly valuable for digestion, but also for deep warming without the direct exposure to the concentrated heat or LED radiation. In the case of Indigo Snakes, these are crepuscular animals that are not particularly known for basking, but virtually all reptiles will bask from time to time, and it is ideal to present the option so that the animal can self regulate its heating and lighting requirements. In my own case I take a commercial plastic hide box, cover the sides with cork bark flats (cut to size and affixed with hot glue), and set the stone or brick on top, or in fact both in order to slightly raise the height of the basking surface so that it is slightly closer to the UVB source and hence provides the high point of UVB radiation within the enclosure. I drilled a channel into this stone with a masonry bit, and the thermostat sensor running the halogen bulb is inserted into the stone through this channel. (Additional details can be found in (12) Heating and Thermostats.)

An electronic thermostat, as previously described, will be relied on to control the heating elements. The pure lighting elements such as the UVB can be controlled through a digital thermostat that provides this option (such as the Herpstats), or separately through a digital or analog lighting timer.

One additional lighting feature that is being increasingly encouraged is something that provides stronger daylight spectrum, as the rest of the lighting array is not particularly bright, and will also leave the cooler end of the enclosure in relative darkness. This is not merely an aesthetic choice, but rather in the attempt to most closely replicate sunlight conditions within an enclosure, more intense daylight spectrum lighting will bring the environment closer such attempted duplication. Since daylight spectrum provides little or no UVB, depending on the precise source used, it can also be used, if you wish, to extend into the cooler “shade” area to provide attractive overall illumination in the enclosure. Bright daylight spectrum also enables reptiles to see better and more naturally, as their visual processing differs from that of human vision.

Two high quality options to completing the daylight spectrum and adding daylight lighting intensity are the Arcadia Natural Sunlight Lamp, or the Arcadia Jungle Dawn LED bar (for which there are other less expensive options available in the marketplace, albeit that likely do not provide the same intensity of light).

The Natural Sunlight Lamp, a fluorescent bulb, offers superior spectrum range, including 2% UVB. However you may not wish to add any additional UVB to your enclosure if you have established the desired level entirely with your existing UVB lighting. The Jungle Dawn will provide much higher degree of luminescence, but perhaps surprisingly it will also add more heat to the enclosure because the visible light range it provides is in itself a potent energy source. Also, the LED strip’s beam is highly directional, hence it will warm surfaces directly in its path below. The bottom line in choosing between the two would be that if you want to add very bright daylight, use the LED strip, but you might wish to confine its range to the basking zone so that its heat is contained therein. Whereas if you are liking to provide a softer lighting across a wider range of the enclosure including part or all of the cooler shaded end, then choose the Natural Sunlight fluorescent. These decisions depend in part on the size of the enclosure and the ability to provide a variance of lighting and heating zones. If, for example, overheating is not a problem, you might want to center the LED strip so that its light is not entirely concentrated in the basking zone, and your reptile can choose to depart the basking zone but still remain in a daylight area that is also perhaps somewhat cooler.

My own system includes not only the above-described Halogen, DHP, UVB and Arcadia Jungle Dawn LED lighting fixtures (all mounted within protective mesh covers), but in fact I provide two UVB bulbs: an Arcadia 6% Forest and an Arcadia 2.5% ShadeDweller Max. The 2.5% bulb comes on first in the morning, and turns off last in the evening, while the 6% bulb overlaps on a midday schedule providing maximum combined UVB for a smaller period of time, along with the Jungle Dawn LED bar. In this way, the 2.5% bulb and graduated lighting and heating schedule is designed to create a dusk and dawn experience, rather than a simple hard on/off schedule for all the fixtures. This dusk/dawn system is what I consider current “best practices” and is gradually being adopted by expert hobbyist and professional (zoo)keepers.

Veteran reptile keeper, breeder and retailer, Todd Goode of LightYourReptiles.com proposes that keepers should provide enclosures with at least three if not four zones of lighting and heating, and that in such a system, we can and should safely exceed the Ferguson Zone guides to some degree, as there is no doubt that wild reptiles often do receive more intense UVB radiation than is provided in the Ferguson Zone guidelines, which is based on a solid theory but still relatively limited data on many species and their natural habits.

ENRICHMENT

On the Resources page you will find links to a number of articles about enrichment. Suffice it to say here that enrichment is a fundamental requirement of best practices in snake husbandry. Size of enclosure does matter, but size is not enough, if you simply provide a water dish and a single hide. Snakes benefit from variety in their environment, and you will benefit from seeing them exhibit more natural behavior, stimulated by the opportunity to explore and investigate their space. Assuming use of the light and shade layout design discussed with regard to heating and lighting, you should provide a warm hide, along with branches, cork bark and the like that provide snakes with security as well as areas of exploration. Humid hides are generally desirable, especially if you have difficulty maintaining sufficient humidity, and provided that you have sufficiently sized enclosures, a cool hide is useful as well, along of course with a large water dish that is replaced or refreshed approximately every other day. These types of enrichment can, at least to some degree, be provided even in smaller enclosures like tubs. Further suggestions can be found on the Resources page, and the introduction of varying and temporary enrichments are also recommended. Snakes will often thoroughly investigate new items introduced to their habitat, providing further stimulation and variety.

HEATING AND LIGHTING SCREEN TOPPED ENCLOSURES

Up until now I have assumed the use of a PVC enclosure or similar enclosure of wood or fiberglass, in which case all of the heating and lighting elements would typically be mounted within the enclosure, suspended from beneath the top or ceiling surface (hence the need for protective guards). However, it’s possible that you might be using some sort of screen-topped enclosure such as a glass aquarium. I don’t particularly recommend these, as all that screening makes it difficult to retain humidity as well as heat, and also provides a dangerous possibility of escape-inclined animals injuring themselves by rubbing their noses against the screening (or other animals like lizards and tarantulas potentially damaging feet and claws by hanging from the screen).

However, if you are using such an enclosure, perhaps for younger snakes until they are large enough for your investing in PVC or similar large enclosures, note that you will not be mounting any of the lighting or heading elements beneath the screen, but rather sitting atop the screen. For this, the incandescent fixtures will require dome reflectors, and the fluorescent lamps will be used in reflectors that can safely sit atop the screen. As with internally mounted heating and lighting, the array should be concentrated at one end, over a basking area, with the other end allowing for a shady area and cooler temperature.

PLASTIC TUBS

I have discussed the use of plastic tubs in the section about enclosures. While I do not approve of tubs as permanent homes for adult Indigo Snakes, we home keepers may require the use of tubs for juvenile animals, until they reach sufficient size that we are able to house them in more substantial enclosures.

With tubs, it is not practical to provide overhead heating. It is conceivable that one can cut out areas of the plastic cover and cement into place wire screening, above which incandescent heating elements could be placed. I may yet experiment with this in the future but as yet I have not done so. Hence for heating purposes I provide admittedly inferior belly heat via the use of heat tape, a remarkable if simple technology that we did not have when I was in the hobby and industry several decades ago. That said, we generally used conventional incandescent lighting fixtures as a heat source, and so without any full understanding of the implications, we were at least providing some minimal UVB radiation, albeit far from enough, but far better than relying entirely on heat mats or other contact heating beneath the enclosure.

Heat tape is readily obtainable from specialty reptile equipment suppliers. Be careful to make certain whether or not you are purchasing wired or unwired heat tape. In the latter case you will also have to purchase wiring and attachment hardware, and learn how to assemble these parts. It is far easier for home hobbyists with small collections to simply purchase wired heat tape, which comes in various widths, and can be ordered to varying lengths and then subsequently easily cut to adjust its length (but not its width).

Some veteran Indigo Snake breeders recommend covering the entire bottom surface of the tub area with heat tape, and have had longtime success maintaining constant temperatures without heat gradients. That said, current conventional wisdom prescribes the importance of providing a heat gradient (as in the light and shad method when heating and lighting from above), thus I choose to cover about half to two thirds of the tub’s bottom surface area with appropriately sized heat tape, leaving about a third of the enclosure bare and therefore somewhat cooler. This serves to provide a hot end and a cool end of the tub, so that the snake can control their own thermoregulation. I set the thermostat’s wired temperature sensor in the warm hide that resides over the heat tape area of the tub, and provide a water dish in the opposite, cool end of the tub.

Here’s an additional tip: In using a Seville brand steel shelving unit, I purchase 2’ x 3’ sheets of 1/4” cork (“Cork Underlayment” available at Lowe’s and other home improvement stores) and cut the cork to serve as shelf liners over the steel wire. This provides an excellent surface for the heat tape which sits between the cork and the bottoms of the plastic tubs.

While this system does not provide overhead incandescent heating or lighting, contrary to popular belief, you can and absolutely should provide UVB light suspended above the tub. (You cannot safely set these reflectors directly onto the plastic lid due to the risk of melting the plastic and potential fire hazard.)

While it is widely known that glass and certain acrylics will filter out UV radiation, blocking the UV spectrum from penetrating through a glass or plastic cover, in fact, UV will penetrate polystyrene tubs and lids, albeit some percentage will be filtered out. On the Resources page I provide a brief report of my own experiments and testing in this area, but suffice it to say that the containers I use (manufactured by Sterilite and readily available from retail chains like Target and Walmart) filter out a range of UVI from 33% to 50% depending on the distance of the bulb from the plastic. With sufficient experimentation using a Solarmeter and controlling for distance and choice of bulb intensity, one can readily control the UVI that reaches the surface of the substrate and or basking area (for example, the top of the hide) to the precise desired Ferguson Zone range. I do this with all my tubs and readjust accordingly as snakes are gradually shifted through progressively larger tubs.

These arrangements are not ideal but if combined with sufficient enrichment—some branches for climbing, pieces of cork bark for exploring, a variety of foods, introduced items of varied interest and exploration such as the occasional cardboard paper towel tool or widely perforated rubber dog toy, along with regular handling and exercise outside of the enclosure—you can raise animals that are both physically and mentally healthy and stimulated, until such time you can move them to larger enclosures with ideally equipped lighting, heating, basking and hiding features.

However, plastic tubs can now be significantly upgraded, presenting the opportunity for economical but quality enclosures for younger Indigo Snakes (and many other reptiles) until they are ready for keepers to invest in “forever homes.” Lori Torrini demonstrates how to install quality heating and lighting in this video:

Heat & Light for Tubs

She uses the Draco Portal sliding doorways and Tub Conversion Kits from Specialty Enclosure Designs HERE.