BASIC REQUIREMENTS
North American Hognose snakes are found in temperate zones that range from a low of well below zero in winter to highs over 100 degrees Fahrenheit during the summer. In spite of these extremes of temperature, Heterodon has been able to function quite effectively throughout its range.
Heterodon’s reputation for adaptability is well known to herpetoculturists who keep and breed them. Of the Heterodon group, the Western Hognose is by far the easiest to maintain, breed and raise, much more so than other species of Heterodon, and can be kept as easily by the novice as well as the expert herpetoculturist.
ENCLOSURE
Virtually any enclosure, which is suitable for other colubrids, is suitable for Western 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 cause higher humidity levels and allow for poor ventilation.
One of the keys to providing a successful enclosure for hognosed snakes is the kind and depth of substrate. hognosed snakes are natural burrowers and 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.
It is important to keep these substrates clean and dry to prevent bacterial outbreaks and 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 or receive daily mistings.
Mexican hognosed snakes (Heterodon n. kennerlyi) may require less water due to the desert environment they inhabit in the wild. However, they should be monitored for dehydration and provided with a shed box if difficulty with shedding (ecdysis) is observed.
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, hognosed snakes 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 hognoses.
Temperature requirements for both the plains hognose and the Mexican hognose range from a daytime temperature of the mid 70’s to the mid 80’s respectively, with a nighttime temperature of the mid to high 60’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
hognosed snakes, like other animals, 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.
Digital timers can also be built into a room to turn on and off lighting, heat pads, and misting systems. This type of system will allow for variable photoperiods during the course of the year. Prior to brumation, photoperiods should be adjusted to coincide with the natural light cycle.
HUMIDITY
Humidity levels for Western hognosed snakes need not be as high as that for Southern or Eastern hognosed snakes. A humidity level of 40% is sufficient for Plains hognosed snakes while 20% to 40% sufficient for Mexican hognosed snakes.
FEEDING
While Western hognosed snakes are the only species of hognoses that can be fed almost exclusively rodents, all members of Heterodon, Leioheterodon, and Lystrophis can be trained to accept rodents through prey-scenting. However, feeding Eastern, Southern and possibly South American hognosed snakes a strict diet of mice may result in premature death from complications arising from fatty liver disease. This subject warrants further study to determine the other deleterious effects from prolonged feeding of mice to Hognoses.
In the wild, Western hognosed snakes feed on a diet of lizards, mice, amphibians, birds’ eggs, and, as youngsters, crickets and other small insects. There have even been recorded cases of Western Hognosed snakes attacking and attempting to eat Ornate Box Turtles. This is especially true of the Mexican Hognose.
Neonate Western hognosed snakes may be fed one or two small 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 Western Hognose should be fed one pinkie each week for the first six months and then 2 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 Western Hognose may be offered 2-3 adult mice 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. By prekilling mice and freezing them, the keeper can ensure that any bacterial infections, mites, lice or other zoonoses are eliminated. 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 also reduces the likelihood of parasite transmission. Ensure you COMPLETELY thaw the mice 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 ensuring it is at least room temperature.
Using a pair of forceps, offer the snake the thawed mouse (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 lizard or toad scent. This is especially important with Mexican hognosed snakes that feed on lizards, toads, and small rodents. Generally Plains 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 should be used; other frogs and toads (such as firebelly toads and dendrobatid frogs) may cause death or injury.
If the young hognose refuses to eat toad or lizard, 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 create a 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, all keepers know 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 risks 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 snakes generally require two years to completely adapt to a captive environment. 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.
Western hognosed snakes lay eggs from June through July and while some may double clutch, this appears to be a rather rare event. According to Degenhardt et al., hognoses may lay anywhere from four to 23 eggs. Depending on whether or not you brumate your charges, your snakes may lay eggs at any time during the spring or summer.
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, coolers, 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 Western hognoses is from 60 to 80 days depending on temperature and humidity. Cranston suggests that eggs kept at a constant temperature of 82 degrees Fahrenheit may hatch in as little as 54 days.
BRUMATION
It is generally agreed that most snakes must undergo a period of inactivity during the colder winter months to rebuild their strength and prepare for the upcoming mating season. Brumation is the period of inactivity snakes in northern temperate regions undergo prior to mating. While brumating, snakes experience limited activity and may not be completely unconscious.
While some keepers insist that snakes must be brumated for them to breed successfully, others have successfully bred hognoses with no brumation whatsoever. In fact, it is unlikely Mexican hognoses from the more southern portions of its range brumate at all. If brumation does occur, this is due more to the drier conditions than temperature changes.
To brumate Western hognoses, 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 the snake 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 North American hognosed snakes is between 50 and 55 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
Of all of the hognose species, the Western Hognose group is by far the easiest to keep and maintain in captivity. Thanks to the work done by many of the U.S. and South American Herpetoculturists, our knowledge of Heterodon in captivity has increased dramatically in the last twenty years. Various color phases, morphs and pattern variants have flooded the markets in the last ten years making Western hognoses affordable to most collectors. Small enclosures with suitable substrate will often suffice for most adults. Tricolors readilly feed on domestically produced mice from birth and rarely need prey scenting. The temperament of tricolors is such that they will often do well in captivity over their lifespan. Moreover, if kept properly, the Western Hognose will reproduce and provide years of enjoyment to its keeper. Its inoffensive nature, gentle disposition, and ease of handling make it both a popular pet and a suitable snake for the beginning herpetoculturist.
Material copyright 2006 by Dennis Desmond, HerpTech Associates.
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