When compared to American Hognose species, the Malagasy or Madagascan hognosed snakes are kept far less frequently than species of Heterodon. This is due largely to the belief that Leioheterodon are more venomous, more difficult to keep, and more expensive. However, if kept properly, the Madagascan hognosed snakes will reproduce in captivity and provide years of enjoyment to their keeper. The inoffensive nature, gentle disposition, and ease of handling of these three species make them a suitable snake for the intermediate herpetoculturist.

BASIC REQUIREMENTS

Madagascan hognosed snakes (Giant, Speckled and Blonde) are found in a variety of habitats from coastal forests and grasslands to montane forests. All three species are found together throughout Madagascar, often competing for resources in the same regions. During the hotter drier periods, Leioheterodon species will remain completely inactive, preferring to stay underground in burrows. They again become active during the rainy season, foraging for amphibians and lizards.

Leioheterodon species generally require higher temperatures and humidity than American Heterodons and due to their larger sizes (4 to 6 feet), larger enclosures. Of the three species, the Malagasy Giant (Leioheterodon madagascariensis) is by far the most commonly seen for sale with the Malagasy speckled (Leioheterodon geayi) and blonde (Leioheterodon modestus) seen less often. If cared for properly, all three species do well in captivity and may even breed.

ENCLOSURES

Virtually any enclosure which is suitable for other colubrids, is suitable for Madagascan hognosed snakes. However, due to their larger sizes, Leioheterodon require larger enclosures than do either North or South American hognosed snakes. Enclosures such as those made by Neodesha, Vision or Cravenhouse, are suitable. Breeders and novice keepers have even used glass aquaria and Tupperware boxes successfully. The main problem with glass aquaria is the tendency for the heat gradient to cause cooler air to settle at the bottom of the cage while the warmer air escapes through the wire top. Glass tops may help reduce heat loss but also poor air circulation.

One of the keys to a successful enclosure for Madagascan hognosed snakes is the kind and depth of substrate. Madagascan hognosed snakes spend much of their time burrowing and remaining underground, coming out during the hotteset part of the day in search of lizards and their eggs. While much more diurnal and active at midday than its American counterpartsLeioheterodon will be much more successful in captivity if provided with the proper type of substrate that will allow for burrowing. Suitable substrates include cypress mulch, dust-free pine shavings, and, my personal preference, CareFresh bedding. Substrates to be avoided include cedar and redwood shavings, bark or mulch, potting soil, and pet litter of any type; these substrates can cause the nares of the snake to become clogged or cause upper respiratory infections. Potting soils may contain phosphates which are lethal to snakes.

It is important to keep these substrates clean and dry to prevent bacterial outbreaks and to keep mold and fungus growth to a minimum. In the case of CareFresh, this substrate can dehydrate snakes so it is important to provide plenty of clean fresh water at all times. This can be accomplished by providing a water dish within the enclosure, large enough for the snake to soak occasionally. Some snakes will not recognize standing water and must be either provided with a drip system, an aquarium bubbler or receive daily mistings. In the wild, hognosed snakes have been observed drinking water droplets from leaves, humus and their own skin.

A hide box is recommended although it may not be used if the substrate is suitable. I prefer an elongate log suitable for the snake to completely conceal itself. Like all snakes, Hognoses are thigmotactic and feel most comfortable when they are in contact with their environment. Therefore, a hidebox or a log which conceals and covers the snake, but which is not too large, is the most suitable for hognosed snakes. A plastic shoebox filled with moist sphagnum moss or shredded coconut provides a suitable hide box favored by these subtropical snakes.

TEMPERATURE

Temperature requirements for the Madagascan Hognose range from a daytime temperature of the mid 80’s to the mid 90’s , and a nighttime temperature of the mid to high 70’s. A basking light in one area of the enclosure should be provided to permit the snake to warm itself at least to the mid 90’s. Although it has yet to be proven, colubrids may benefit from full spectrum (UVA – UVB) lighting. I provide full spectrum illumination in the enclosure based on natural photoperiods.

While some snakes are thigmothermal (require contact with warm surfaces) others absorb warmth from sunlight. To create a warm gradient within the enclosure, I provide an under-surface heat mat at night set on a timer; this permits the snakes to move onto or away from a warmer surface at night. Warm temperatures are important in maintaining optimal health by aiding in digestion, fighting disease, and facilitating growth and hormone development.

A word about heat rocks – don’t use them! More fires and animal injuries occur from these types of heaters than any other product. Snakes lack sensitive nerve endings along their ventral surface and therefore are unable to detect high temperatures on surfaces. Since the heat radiates from a rock surface independent of the air and surrounding temperatures, snakes have difficulty recognizing heated surfaces that might cause injury. Instead, heat pads placed beneath an enclosure with more moderate temperatures will provide a safer environment.

PHOTOPERIOD

As with other reptiles, Madagascan hognosed snakes require regular day and night cyclical periods to function normally. While a day/night photoperiod of 12 and 12 can be provided with effective results, varying the daylight and dark periods to mimic nature provides a more realistic setting and may contribute to a more successful breeding program. Timers which turn lights on and off can be had for very little or, for more precise and more reliable models, quite a bit more.

I have installed digital timers into my herp room to turn on and off lighting, heat pads, and misting systems.

HUMIDITY

Humidity levels for Madagascan hognosed snakes should be higher than for North American Hognoses. A humidity level of 50% to 60% is sufficient for Madgascan Hognoses from the montane forests and coastal areas while those from the grasslands can be kept at 40 to 50%. If you are unsure as to the region your snake is from, it is better to err on the dry side and observe the snake for any skin dryness or dehydration. By misting the cage every other day, you can both increase humidty as well as provide additional drinking water for your captives. Recently, ionizing water falls have been showing up in various stores that produce mist and bubbling water. There is no indication these are harmful in any way to captives but their use should be monitored.

FEEDING

In the wild, Leioheterodon feeds on amphibians, lizards, small snakes, birds and their eggs. Bill Love relates a story where he came upon a Madagascan Giant hognosed snake rooting in the sand for lizard eggs. In captivity, Leioheterodon will readily accept mice and small rats.

While Leioheterodon is known to be rear-fanged and possess a Duvernoy's gland, the level of toxicity remains unclear. According to Henkel, Leioheterodon is not toxic to humans. However, as with some other colubrids (Ramphiophis) Leioheterodon also uses constriction to kill larger prey. On numerous occasions I have noticed my Leioheterodon geayiconstricting a still-moving mouse, holding it firmly in its jaws. It is not unusual for my Leioheterodons to pin the prey item against a log or enclosure wall before beginning the swallowing process.

Neonate Madagascan hognosed snakes may be fed one or two pinkie mice per week; this is sufficient to maintain a healthy weight. Many breeders and herpetoculturists overfeed young snakes in the hopes of having them reach a larger size more rapidly. This can result in obesity problems later on. It is better to feed snakes enough to keep their weight at a steady growth rather than have them grow too fast. By the same token, intentionally stunting animals by feeding them too little (as is done with some boas and pythons) can also cause serious physical damage.

Typically a neonate Madagascan hognosed snake can be started on one or two pinkies each week for the first six months and then two to four pinkies per week for the next 6 months. As the snake grows older and increases in size, you may increase the size of the food item. As an adult, a Madagascan hognosed snake may be offered 2-3 medium sized adult mice, or one juvenile rat every 7-10 days.

Snakes should always be fed mice that, as a minimum, have been prekilled. The reason for this is multifold: snakes that do not immediately attack and eat a prey item may be subject to gnawing by the mouse resulting in serious injury. Also, a live mouse grabbed at midbody may be able to inflict a serious bite on the snake. Lastly, it is much more humane to feed prekilled mice to the snake.

Generally I would suggest feeding mice that have been prekilled, frozen and then thawed. Feeding thawed mice (and amphibians) also reduces the likelihood of parasite transmission. Ensure you COMPLETELY thaw the food item prior to feeding the snake; if you don’t, the partially thawed food item could cause severe gastric distress and kill the snake. Prior to feeding the food item to the snake, pinch the belly of the mouse or other food item ensuring it is at least room temperature.

Using a pair of forceps, offer the snake the thawed food item (A note of caution here: NEVER thaw a mouse in a microwave oven) either in the enclosure or in a special container specifically used for this purpose. Remember to wash your hands prior to and after offering food; this will reduce the chance of a stupid feeding error (SFE). While there have been few instances of envenomation by hognoses, reducing the risk of a feeding-related bite is safest.

When feeding neonates, pinkie mice may be scented with frog or toad scent. Generally captive born Madagascan hognosed snakes will take unscented mice. Rubbing a pinkie mouse with toad paratoid gland mucous or toad urine will usually be enough to get the snake to feed. WARNING: only American Bufonids, Ranids or Scaphiophis should be used; other frogs and toads (such as firebelly toads and dendrobatid frogs) may cause death or injury. Along the same vein, Plethodontid salamanders may be consumed.

If the young hognosed snake refuses to eat toad or lizard scented mice, the pinkie can be split-brained; this smell sometimes entices reluctant snakes to feed. Occasionally young snakes can be placed in a small container with the food item in a dark quiet place and they will feed on their own.

You may also create frog or toad slurry to use as a scenting material for pinky mice. While this has been shown to be most effective with Eastern hognosed snakes, the procedure works well for any hognose that refuses food. Take a couple of toads or frogs that have been prekilled and then frozen for two weeks to kill parasites, place them in a blender with a little water, and blend away! (Be sure to get your parent’s or spouse’s permission first – and don’t tell any houseguests). Pour the mixture into ice cube trays and freeze. Next time you feed your hognose, thaw out a cube, soak the pinky mouse in the mixture and then try to feed the snake. As a substitute, the mixture can also be poured into a water dish. This process can also be performed with lizards.

As a last resort, you may have to force-feed your charge until it begins feeding on its own. This can be a potentially dangerous maneuver and if you feel uncomfortable attempting to force feed the snake, have a qualified veterinarian perform the procedure.

Initially, a vitamin supplement such as Nutrical can be used to build strength and provide necessary nutrients. For a neonate, 5cc of Nutrical every two days is sufficient to maintain health. This can be supplemented with mouse legs and lizard (Anolis) legs coated with Nutrical to facilitate the feedings. Do not use metal tweezers or forceps to force the snake’s mouth open; this can result in severe damage to the snake’s mouth, glottis, or jaw. Instead, use a flat toothpick to gently pry open the young snake’s mouth, slowly insert the syringe (without the needle) approximately a third of the way down the throat of the snake, expelling the Nutrical into the snake’s stomach.

A pinkie pump, which liquefies pinkie mice, can also be used to introduce complete animals into a snake’s stomach.

Force-feeding adult snakes generally requires two people. Coating the food item in Nutrical will also facilitate the feeding procedure. Using a wooden nail file or Popsicle stick, gently pry the snake’s mouth open. Insert the food item, head first, into the snake’s mouth. The snake’s head will have to be held very carefully to prevent injury, while gently forcing the mouse farther down the snake’s throat. The snake may initiate a feeding response automatically. Otherwise, you may have to continue to apply slight pressure to the snake’s jaws while massaging the snake’s neck so the mouse proceeds down the snake’s throat. If you are unable to move the food item far enough down the throat, the snake may regurgitate the item and potentially risk injury.

Of course, you as a keeper should understand that there are some snakes that simply fail to thrive and never take food in captivity. In the wild, these snakes would simply wither and die. In captivity, you may be forced to force feed these snakes for many years. In the end, only you can decide if keeping the snake merits the risks, or if the risk to the health if the snake outweigh the benefits.

BREEDING

Hognosed snakes reach sexual maturity at two years of age in captivity. At this point, a female can be introduced into a male’s enclosure for breeding. By introducing the female into the male’s enclosure, it will be easier for the male to follow the pheromones (sexually induced scent gland chemicals) and locate the female. Again, many snakes have bred successfully despite being kept together year round.

Wild caught Madagascan snakes generally adapt to a captive environment within six months to a year. Although younger snakes will adapt more readily and more quickly, some wild caught adults may never adapt at all. The comfort level of the snakes is critical to successful captive propagation.

Madagascan hognosed snakes breed in August and lay eggs during the months of November and December. Male Madagascan hognosed snakes may engage in ritualized combat, the loser retreating from the successful male. The successful male will then pursue the female initiate ritualistic chin rubbing along her back. Once accepted by the female, the mail will insert one of his hemipenes into the female's cloaca. Mating may last several minutes or several hours. After 60 to 80 days of gestation, the female hognose will lay the eggs in a shallow pit or under detritus. Although the number of eggs laid may number in the 20's, it is more common for an adult female to lay from eight to twelve.

Prior to the female laying her eggs, you should prepare a suitable nesting box with a vermiculite/water mix. A plastic shoebox half-filled with moist vermiculite, on a 1:1 ratio of water to vermiculite, measured by weight is most commonly used. To increase the likelihood the female will enter the box, cut a hole in the top of the box through which the female can enter and exit easily. Be careful not to leave any sharp edges that may result in cuts. Place the shoebox in the portion of the enclosure that has the most constant temperature, preferably away from the basking light. With any luck, the female will seek out her nesting site and lay eggs just after a pre-parturition shed.

INCUBATION

Once the eggs are laid the box should be placed in an incubator. Our “incubator” consists of a melamine cabinet with very strict moisture and temperature controls. A temperature range of 73 to 88 degrees Fahrenheit (23 –31 degrees Celsius) appears to be sufficient. Depending on the temperature, hognose eggs may hatch in a shorter or longer period of time.

There are many types of incubators available on the market, or you can manufacture your own. The HOVA-BATOR was originally designed to hatch chicken eggs but it can be modified to serve as an incubator for snake eggs. Most backyard breeders simply make their own incubators out of old refrigerators, cabinets, or aquaria. As long as there is little temperature or humidity variance, the eggs should do well.

Occasionally if eggs are not transferred soon enough or become desiccated (dried out) they may seem to cave in. Once the humidity levels are elevated the egg may regain its shape and hatch normally. Other eggs, due to mishandling, infertility, or rapid temperature changes may collapse, develop mold and turn yellowish. These eggs should be separated from viable eggs and discarded.

During the course of incubation, you may carefully examine the eggs, using a process known as “candling.” When candling eggs, be sure not to rotate the eggs because the embryo may become detached from the wall of the egg or the yolk may rupture or smother the embryo. To candle an egg, hold the egg with the thumb and forefinger of one hand while shining a flashlight from behind the egg with the other hand. If the egg is fertile, you should be able to see blood vessels developing within the yolk and the dark eye spot of the embryonic snake.

Check the eggs periodically to ensure they are not rotting or covered with fungus or mold. Because the shells are permeable and exchange moisture and oxygen vital to the survival of the embryo, no chemicals or toxic substances should be used on the eggs during development.

Typical incubation for Madagascan hognosed snakes is from 60 to 80 days depending on temperature and humidity.

BRUMATION

It is generally agreed that Madagascan hognosed snakes must undergo a short period of inactivity during the cooler winter months to rebuild their strength and prepare for the upcoming mating season. In Madagascar, hognosed snakes remain active and may seek food or water on warmer days. According to Bill Love, Madagascan hognosed snakes can be observed basking on warmer days during the mild Madagascan winters.

To brumate Madagascan hognosed snakes, feed them heavily a month ahead of time. This will prepare them for the two to three month period when they do not have access to food. After you observe that the snakes have defecated, do not feed them for another two weeks, this will allow them to completely clear their bowels. If the snakes are brumated with undigested food in their guts, the food will decay and cause death.

Brumating snakes at the appropriate temperature is extremely important. If kept too warm, bacteria and parasites in the snake’s system could remain active. Since the snake will have been placed in a state where its immune systems have been lowered, it may fall victim to disease or infection that they would normally be able to fight. If a snake is kept too cold, they may unable to recover from their state of torpor.

The suggested brumation temperature for Madagascan hognosed snakes is between 55 and 60 degrees Fahrenheit. While some keepers suggest gradually dropping the temperature over several days, there is evidence to suggest that this may result in respiratory infections and an overall reduction in the immune system of the snake. Instead, once the snake’s digestive system has cleared, it can be placed into a container at the appropriate hibernating temperature.

A suitable container may include Styrofoam boxes, Tupperware containers or the snake’s normal enclosure. A substrate such as newspaper or CareFresh bedding should be placed in the “hibernaculum.” You should also provide a hide box and a water dish filled with fresh water. Snakes will seek water during their brumation period. Since you have already been altering the photoperiod (as discussed earlier) to coincide with the seasons, the snakes will be ready for full brumation.

SUMMARY

When compared to American Hognose species, the Malagasy or Madagascan hognosed snakes are kept far less frequently than species of Heterodon. This is due largely to the belief that Leioheterodon are more venomous, more difficult to keep, and more expensive. However, if kept properly, the Madagascan hognosed snakes will reproduce in captivity and provide years of enjoyment to their keeper. The inoffensive nature, gentle disposition, and ease of handling of these three species make them a suitable snake for the intermediate herpetoculturist

Material copyright 2006 by Dennis Desmond, HerpTech Associates.