Zoo-pedia > Corn snakes and other ratsnakes - Natural...

Corn snakes and other ratsnakes - Natural History, captive husbandry and breeding.

By Kevin Stevens

A note from the author; This guide was wrote some years ago (approx 1993), intended for publication in a series of booklets. It was placed on the site in around the year 2000, and had not been updated or altered since it was written. In April 2006, a series of criticisms were aimed at this guide from keepers on an internet forum, and it was thought best to update and alter some of the keeping techniques and advice given. Although the author cannot agree with some of the criticisms levelled at the guide (he felt some criticism was a little blinkered and based on experience of too small an amount of snakes), there were some areas that his advice had evolved in that time and had changed. We would always advise that this care sheet (it is the one covered with, and given to all our customers at the time of purchase) be read in addition. We hope this note does not take away your enjoyment and usefulness of the guide.

Introduction... All snakes either create fear or fascination within most people, and perhaps both in some cases! This creates people who carry on their lives being either wary of them or are snake keepers. This book is for the latter.
As with all "exotic" pets, and for that matter any pet at all, ensure adequate thought is given to the amount of commitment required. Some reptiles end up not wanted, this is often due to lack of correct education at the point of purchase. Far too often they are sold by pet shops that do not understand any reptile needs. Our advice is to seek a reptile specialist rather than a general pet shop, and then ask as many questions as you can to ensure they deserve the title of reptile specialist - remember just like any walks of life there are good and bad.
It would be fair to say that realising how to breed species such as Cornsnakes made the hobby what it is today. In the middle of the 1980's there were great advances made in techniques and the understanding of what made them tick. Breeding suddenly became commonplace and the birth of Herpetoculture was made. Since then the art has progressed and enthusiasts are now successful with more difficult species and even producing "man made" colour and pattern morphs of various species. It is now quite rare to purchase Corn snakes and many other Ratsnake species that have been taken from the wild. This can only be a good thing, producing strong healthy specimens without parasites and without depleting wild populations. Captive bred reptiles will always provide the owner with greater satisfaction

Natural History... Corn snakes occur through many of the states of the U.S.A., especially in the south. They occupy a wide range of habitats from prairie, wood land and sometimes even marsh land. They often are found around human habitation. Other ratsnake species are found in similarly varying habitats throughout the areas mentioned above.

Description... The Corn snake in its "wild state" can be quite variable in appearance, depending on geographical variation. The ground colour can be grey, buff, brown or orange with saddle markings ranging from deep red, orange or brown. There is a characteristic checkerboard pattern on the underside. Populations of the above mentioned colour morphs occur, even in the wild. For example there are areas where Anerythristic (lacks in red pigment) Corn snakes occur in the wild in large numbers. Most of the other colour morphs are man made, the hobbyist is likely to encounter Snow (very pale coloured with little pigmentation), Amelanistic (lacks in black, so very bright reds and oranges are left), Ghost (pale grey background, often with lilac saddles), Candy (white background with red saddles), Creamsicle (contrasting shades of creamy orange) amongst many others. This has then been taken further by producing pattern variations of many of these, striped and "motley" (form that has no ventral checkerboard pattern and the saddles fuse together) are available. Man made cross breeds are also on the market, notably the Jungle Corn which is a Corn snake crossed with a Californian Kingsnake. The resulting offspring are quite unique with the best examples having a vivid golden yellow background colour with contrasting beige saddles.

Full size for most Corn snakes is about 1.5 metres. There are brief descriptions for many of the other Ratsnake species in their own accounts further in this care sheet.
Longevity... The author had a Texas Ratsnake that lived for around 27 years. As we gather more information regarding the correct husbandry of reptiles it can only be assumed that the lives of captives will be longer and longer.

Choosing your Corn snake or Ratsnake... We suggest a visit to your local reptile specialist. Try to avoid the pet shops selling everything from cats and dogs to budgies, they are unlikely to have the knowledge and expertise required to make a successful purchase. As mentioned, even so called reptile specialists vary. Put them to the test, chat to them, ask questions, look how clean the vivariums are, have the animals got clean water and ample food? Do they take pride in what they sell? Are they only interested in selling you what they want rather than listening to your needs? Do they sell all the necessary specialised heaters and lighting, or are they trying to palm you off with a household bulb? What is their back up service like (own vet, etc.)? Next pay attention to the animals. If you have successfully managed to convince yourself that you have found a reputable reptile specialist they should all be looking very healthy. Are they well rounded or looking like a Toblerone bar of chocolate? Are they alert? When they scent the air with their tongue is it a fork shape or are the ends stuck together? Is the vent region clear? Do the eyes have a build up of unshed skin over and / or around them? Are there records available for the feeding details? Indeed, are they feeding? All these points should give a clear indication of the health status of any prospective purchase.
Housing... Corn snakes and many other species are housed in a similar manner. Any variations will be mentioned in the later section regarding the other species. It is important to keep in mind that snakes are generally quite nervous and relatively easily stressed. For this reason it is important to abide by one of the golden rules, house them in relatively small vivaria. Many new keepers find this fact a little disturbing, they expect snakes to be similar to other pets that require large areas of space. Do this and you risk a new pet disaster, they often will not feed if housed in large cages due to levels of stress.

As a hatchling it is best to house in a container either of the small size plastic tank variety (perhaps measuring approximately 23cm by 15cm by 15cm), or a lunch box with air holes drilled. This tends to suffice until about three to four months of age (at average growth levels), and then the inhabitant can be moved to the next size, usually measuring about 36cm long by 20cm wide and 15cm high. Many manufacturers offer suitable plastic tanks this size and the next - approximately 45cm long x 30cm wide x 15cm high. Juveniles should be ready for this size at about 6 or 7 months of age. Notice how the height has altered little throughout, most species are not particularly arboreal (climbers) so floor space is much more important. Some breeders keep them in this size of tank for the rest of their lives, but most pet keepers prefer something larger. Wooden vivariums are very suitable, often they are of melamine faced chipboard construction with sliding safety glass front doors. Real wood can be utilised, but it must be well varnished with a non-toxic product. Most adult ratsnakes are adequately housed in vivaria measuring 30”x15”x15” (since this care guide was wrote, a swing away from small vivaria by many keepers has been observed, many keepers stating that the snake should equal the length and depth of the vivaria, i.e, a five feet long snake should be housed in around a 36”x24” or a 48”x12”. This author cannot fully agree with this due to the resulting problems often presented to him, problems include fussy feeding or none feeding. Not all snakes are prone to this, but as a result he feels it best to be safe than sorry and provide a vivarium that allows the snake to feel safe, happy and secure). Glass fish tanks are not entirely suitable for housing Corn snakes, amongst other problems are the ease they can usually escape from them. It is important to remember that snakes are the original Houdini!

Heating... For the average pet keeper heat mats are the most suitable. In the wild most species of ratsnake tend to hide during the day, especially during the hot summer months and only bask in the sun in the early spring or late summer. Most of the year they come out in the evening and sit on something that has warmed in the sun, once warmed they go about their lives. This accounts for why heat mats used as "under floor" heating make an excellent source of heat for them.

When using plastic tanks the mat can be placed under them so the heat comes through the bottom of the tank. This is not possible with wooden vivaria, if the mat is placed underneath the heat will not penetrate inside. The most important thing to remember is that with all installations heat no more than 50% of the vivarium. For example, if you intend to heat 60cm x 30cm floor space use a heat mat that is no bigger than 30cm x 30cm. Many keepers do not provide any form of temperature control when using heat mats in this manner but it would be safe to say that it would be advisable.

When using heat mats it can be difficult to raise the air temperature sufficiently. This is because most mats provide infra-red heat which is only efficient at raising the temperature of solid objects. The air temperature is often only raised by about 4C, but your snake's temperature (being a solid object) will be much higher. This is quite acceptable, and as long as your snake feeds and defecates correctly there is very little to worry about. There is no real reason to be using any other form of heating other than heat mats for most Ratsnakes. If you chose to use other methods of heating, say ceramic heaters, the temperature to aim for in the "warm end" of the vivarium is 28C

Lighting... Some keepers prefer to provide lighting in one form or another, whether it be full spectrum or household incandescent. There is no real requirement for most snakes, and many actually settle better in dimly lit vivaria. The author has never provided any form of lighting for all his Corn snakes and various species of Ratsnakes, but has successfully bred them for many years. If the owner intends to use the vivarium for décor and thus needs to provide some form of lighting, household incandescent bulbs are probably the best choice. Use a low wattage of around 25w and these will not get warm enough to burn the snake. It would be advisable to connect them to a thermostat of the dimming variety, thus preventing them over heating the vivarium and to fit a guard to stop the snake making contact. Do not use simple "on/off" thermostats as the constant flashing of a bulb going on and off would be very stressful.

Feeding... Rodents are the staple diet. Hatchlings should take new born mice (known as pinkies) once they have completed their post hatch slough (their first shedding of skin, normally completed no more than a week after hatching). When established hatchlings should feed on two or three pinkies about every four days. The size of food increases with growth of the snake, at the age of about three or four months they should take mice that have started to become furred (these are known as fuzzies or furries). Again, three fuzzies about every four days is an ideal amount to promote a healthy growth rate. If fed correctly your snake should be able to eat small adult mice at about nine months of age, again at about the same rate. After a further three months, to stop obesity, it is best to decrease the amount to one or two small adult mice about every seven days. This author prefers the use of two small adult mice rather than one large mouse, snakes are less prone to regurgitation when given smaller feeds.
There is some discussion regarding the use of vitamin and mineral supplementation, some keepers provide them, others not. The author is of the opinion that it is not required for snakes fed on a healthy diet. This means that all rodents used must have also been fed a good quality diet. Supplementation is only given to snakes that are "under the weather" due to illness or other problems.

The last point to mention is the use of live prey. Nearly all snakes offered should take defrosted dead rodents with little or no problems. The use of "live feeding" should therefore be frowned upon, there is no advantage over dead. Not only is it unnecessary suffering to the rodent, but the snake itself can be severely injured. The author has seen many cases where owners have left a rodent in for their snake to eat only to return to find the tables have been turned and the snake has become the meal. The worst case I have ever seen was an adult Burmese python (Python molurus bivittatus) that had its face and eyes eaten by a rat, the snake obviously did not survive.

Other husbandry considerations... Two distinct methods of keeping these snakes exist. Some keepers prefer to furnish their vivariums very simply, using newspaper as a floor covering, a card board box or washable ceramic hide and a water bowl. Others décor their cages with plastic plants, branches, rocks and use substrates such as beech chip as a floor covering. There is no real reason why you can't take either option, but remember that the latter will require a little more up keep to ensure levels of hygiene are maintained. The most important things to remember are the provision of a hide area and a water bowl, after that (within reason) it is up to the keeper. Keep in mind that it is best to follow some simple guidelines: place the water bowl in the cool end of the vivarium, do not use substrates such as corn cob as this sticks to the food (for hatchlings it is advisable not to use any at all and use kitchen towel instead), do not use damp substrates such as orchid bark, try to provide at least two hide areas (one in the cool area and one in the warm) and do not use live plants - they will invariably die. Many provide a wet box in the form of an empty plastic container (with a hole cut to allow entry) and filled with sphagnum moss, this will help when the snake sloughs its skin. In the authors opinion it is not a good idea to utilise cat litter, this is a desiccant which can literally dry out the lungs of a snake if the powder is breathed in.
One thing to remember regarding any of the mentioned substrates is that if too thick a layer is placed over the heat mat this will cause "thermal blocking". In simple terms this means the heat cannot escape, thus causing a risk of over heating. This may result in burns to the snake, cracking of glass and plastic vivaria, burning out the heater and even a fire hazard. Do use any more than about 10mm in depth of substrates over any heat mat.

Health and Hygiene... By keeping your Corn snake in the manner described you are certainly minimising health problems, but remember, as with all pets the threat of illness can never be eliminated totally. Commonly seen ailments include internal bacteria and parasites such as protozoa (characterised in lack of appetite, runny and smelly stools, lethargic behaviour and dehydration) and nematode worms (large appetite with loss of weight, lethargic behaviour, dehydration and visible worms in the faeces passed), respiratory infections due to cool conditions (excessive mucous from mouth and nostrils, bubbles from nostrils, lethargy, forced breathing), mites (often snake mites or sometimes red mites) and skin conditions (blisters and slough related). Conditions resulting from neglect are often presented, thermal burns from unguarded heaters, noses rubbed raw from the use of abrasive vivarium materials or sharp edged glass and skin infections from poor hygiene. The treatment for most of these conditions is possible, but obviously prevention is better than cure. From our experience it seems that many reptiles' lives can be cut short by up to two thirds when kept incorrectly, we often see snakes that have survived for about two or three years that suddenly succumb to one of the ailments listed. It has to be said, that the most frequently reported ailments are generally down to a misunderstanding of a snakes requirements, poor feeding down to large vivaria, over handling etc etc.

Vivarium hygiene is of utmost importance, ensure that a daily spot clean along with daily water changes happens as matter of course. A full strip down and sterilisation of the contents of the vivarium must occur at least once every ten to fourteen days. Ensure only reptile orientated cleaning products are used, some household detergents can be toxic to reptiles. One question often asked when mentioning hygiene in reptiles is Salmonella. Over recent years there has been some propaganda within the media suggesting that this is a problem. Reptiles can carry Salmonella, but no more than any other pet. Indeed it is often quoted that around 1 in 3-4 humans also carry Salmonella, so you are just as likely to be infected from the guy who has just prepared your pub lunch or take away pizza. The same precautions should be taken that are recommended for all animal handling, that is wash your hands afterwards with an antibacterial hand wash. The author has spent nearly all of his life around reptiles with no ill effects whatsoever.

Sexing... Snakes can be sexed from day one, straight out of the egg. There are three commonly used methods, the only one to be tried by new snake keepers is to have a visual inspection of the tail area. A snakes tail starts from the vent or cloacal opening. If you gently turn your snake so you can view the underside you should clearly see this opening. A male will have a longer tail with long bulges at the base, a female does not have these bulges and also exhibits an obvious taper. Other methods include surgically probing (a special probe is inserted inside the cloaca, this will travel further in a male than a female) and "popping" (a special technique where the hemipenes are inverted) but neither should be attempted by keepers other than an experienced herpetologist.

Other general points and considerations... If you are keeping a youngster be aware that during the growing period they will need to shed (or slough) their skin. At this point in their life they will slough about every three or four weeks. You will first notice the skin becoming very white in appearance, the eyes are also covered in skin and will also take this "milky" appearance. After about seven days the skin will lough, and should come off in one piece. If not they have almost certainly become a little too dry, place them in a damp area (we often use damp pillow cases) and it should all come off. They will now exhibit nice and bright colours. As they become older obviously the growth rate slows and they will not slough their skin as often, perhaps three or four times a year.
Most keepers would like their pet to be "silly tame", and in this case this is easier than many reptiles. Corn snakes are naturally more resilient to handling and therefore easier to tame than many reptile species, but still start slowly, and not too early in life. This is best done by introducing your hand into the vivarium gradually and letting him get used to the idea. Try this for a few days. Next slowly try to touch him whilst still in his vivarium, with a bit of luck he'll let you gently stroke him. After a few days of him getting used to this idea he may even let you gently coax him onto your hand (don't grab or forcibly hold him), and he may even let you remove him from his vivarium (since the writing of this article, this advice has been criticised by other keepers – the author would like to point out that this article was originally intended for a book, and the publisher asked for a section regarding taming a Corn snake. As Corn snakes are a naturally tame species, the author struggled to write a sentence or two with regards on how to tame a generally naturally tame species – hence the slightly silly taming advice!). Adult snakes need to have their bodies supported at least in two places, do not dangle your snake! Do remember that even tame snakes will do best if not out of their vivaria for long periods of time - the conditions they require are in here not in your living room!

Other considerations include what can be housed with your Corn snake. If you decide that you would like a companion for your pet first consider another Corn snake. If you plan to keep them together in the same vivarium you must separate them at feeding time and keep a careful eye on them for an hour or so after reintroducing them. This way you will ensure no accidents happen (in that one tries to eat the other) due to the scent of the rodents. The author suggests it is even better not to house them together at all. If you are to house more than one together other suitable species include many of the North American species of Ratsnakes, but Kingsnakes definitely must not be mixed. These are natural eaters of other snakes.
Corn snakes are easy to breed and will do so in a variety of conditions. The author breeds this species on a relatively large scale and finds the following regime the most productive. Adult breeders must be well fed and in good health. A period of hibernation (cool temperatures of around 10C) is considered vital by this author to ensure the females are "keyed" into the seasons and that males produce viable sperm. Three months at these temperatures is sufficient. Do not feed three weeks prior or during hibernation. Upon resuming normal temperatures ensure females are very well fed. Introduce them to each other about four to six weeks after hibernation, and continue to do so until the female is obviously gravid. The female will slough her skin about ten days before laying the eggs (and again afterwards). Provide a plastic container with a layer of damp material such as sphagnum moss or peat as a laying box. She will produce on average fifteen eggs (twenty six is the largest clutch I have seen a Corn snake produce). The female will need to be very well fed to regain her weight lost. It is possible to "double clutch" (two clutches produced in one year) if the females are very well fed. The eggs should be transferred to another plastic container (with air holes) and half filled with damp vermiculite. Humidity should be at around 95% throughout the incubation, and a constant temperature of 28C is ideal. At these temperatures the eggs should hatch in about sixty days. Corn snakes will breed without hibernation, but it can be a little more “hit and miss”, clutches can be more randomly produced and smaller hatching rates due to poor fertility have all been noted.
Other Ratsnake species commonly seen in captivity...

Great Plains Ratsnake (Pantherophis emoryi) – was once considered to be a sub-species of the Cornsnake, but not as commonly kept. This is a shame, as in some respects they are a better choice - they tend to be a bulkier and more robust snake as a hatchling and present few feeding problems. Colours can be variable, the most common being a greyish background with greenish brown saddles. Kept in the same manner as Corn snakes.
Black Ratsnake (Pantherophis obsoleta obsoleta). - This is the nominate form of a wide ranging species which covers several sub-species. The Texas (P. o. lindheimeri), Yellow (P. o. quadrivittata) Everglades Ratsnakes (P. o. rossalleni), Grey (P. o. spiloides) and Black Ratsnakes all make good captives that tend to do well in captivity, but keep in mind they all tend to grow larger (on average around 2 metres) and are often a little more aggressive or temperamental. Colours and patterns vary considerably throughout, one of the more interesting points is that many are blotched as babies and turn striped or patternless as they get older. As with the Corn snake there are various colour and pattern variations, some of the more interesting include Leucistic Texas Ratsnakes which instead of the usual browns and orange are a beautiful alabaster white with blue eyes, Albino Yellow Ratsnakes that are lemon yellow with purple markings and "Bubblegum" Ratsnakes, a man made inter-breed consisting of a gene pool collected from Albino Black Ratsnakes, Albino Everglades Ratsnakes and Albino Yellow Ratsnakes. These are a vivid bubblegum pink colour with yellow heads, not to everyones taste! Keep similar to Corn snake but provide a larger vivarium as an adult, approximately 100 to 150 cm x 50 cm x 50 cm should be ideal.
Bairds Ratsnakes (Pantherophis bairdi) - A lovely well suited snake for the beginner. Each individual scale is a silvery grey colour with the skin underneath being orange. Nearly always an easy snake to live with, rarely biting and on par with the Corn snake.
Trans Pecos Ratsnake (Bogertophis subocularis) - A slender snake with obviously large eyes usually tan in colour with a series of "H" shaped markings along the back. Not an easy snake to keep and best suited to more experienced keepers. If an attempt to breed this species is to be made remember that they copulate and produce eggs much later in the season than most ratsnakes, August and September is the usual norm for egg production.
Fox snake (Pantherophis vulpina) - One of the best choices for beginners, I have never come across a nippy Fox snake. Not the prettiest of snakes but this is amply made up by the wonderful temperament. Does not like high temperatures, keep no warmer than about 25C and you should do very well. Likewise if you intend to breed from your adults hibernation must be cooler than a Corn snake. An ideal temperature would be about 5C for about four months.
Four-lined snake (Elaphe quartuorlineata). - Three subspecies are now current but the only ones commonly seen in captivity include Western Four-lined (Elaphe q. quaruorlineata) and Eastern Four-lined (Elaphe q sauromates). Visually they are very similar when hatchlings, both are grey with black blotches (the Eastern has a tell tale red dot on its head which the Western never has) but as adults the former keeps its pattern but turns a yellow / brown with brown blotches, and the latter a fawn to grey green with four longitudinal dark stripes. Often they are a very placid but larger ratsnake that tends to be a good vivarium subject. For captive care see notes for Elaphe obsoleta. One note - fussy feeders can often be persuaded by the provision of a wet humid area. In the wild they often are seen hunting during wetter conditions.
Leopard and Ladder snakes (Zamenis situla) and (Rhinechis scalaris) - Not very common within collections but sometimes kept . The Leopard snake superficially resembles Carolina Corn snakes, with a grey to fawn background colour and red blotches. The Ladder snake is another species that is visually different as a hatchling, at this age they are an olive green with a ladder pattern (hence the name) running the length of the body - as an adult this fades and becomes two longitudinal stripes. These are definitely not for beginners, the former is nervous and needs delicate care and attention, the latter is easier to maintain but is aggressive and not for the faint hearted.
Russian Ratsnake (Elaphe schrenckii) - Not seen in captivity as often as they where, but do make very good captives. A glossy black snake with dirty white or yellow bands. Usually a good choice as they are often mild mannered and don't grow too large. To successfully breed this species hibernation must be quite severe. Temperatures of around 5C for about four or five months are best suited to successful egg production.

Taiwan Beauty snakes (Orthriophis taenuira friesei) - Can attain a length of almost 3 metres. One of the real beauties, colours are a mixture of yellows and greens and the pattern changes from blotches to stripes along the body. Can be aggressive but a tame placid individual makes an enjoyable and impressive addition to any collection. Vivariums must be spacious for a large adult, the absolute minimum would be around 150 cm x 50 cm x 50 cm. Climbing branches are always appreciated. Radiated Ratsnakes (Coelognathus radiata) - A stunning species, but not easy to cater for and aggressive. A yellow brown colour with longitudinal stripes that run only part of the body. The most impressive thing about this species is the defence posture, they lift their anterior section of the body into the air, from a "S" shape, gape their mouth and flatten their necks. This forms a huge round shape marking on the neck which gives the impression of huge eyes and must go some way to deterring predators. Not an easy snake to keep, general pointers include the provision of wet humid areas and do not hibernate them at low temperatures, a slight cooling to about 20C is sufficient if you wish to attempt breeding.
Other species sometimes seen include Mandarin Ratsnakes (Euprepiophis mandarina), Night snakes (Pseudelaphe flavirufa), Japanese Ratsnakes (Elaphe climacophora) and Red-tail Racers (Gonysoma oxycephalum). Unless in the hands of a very experienced herpetologist they are not a good choice, they are difficult to cater for and most offered for sale are not captive bred. Many wild caught reptiles carry huge parasite burdens and are difficult to acclimatise to captive conditions.