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Value Vivariums would like to thank Robert D. Gilbert, and www.reptilekeeper.co.uk, for the following information:
Habit
The western hognose snake, Heterodon nasicus nasicus, is a small Colubrid snake from North America. Heterodon means variable teeth while nasicus means nasal or nose. Thus we have a snake that is rear fanged with a funny (upturned) nose or snout. These snakes average between one and a half to two feet long with a record length of just under three feet. These snakes are quite chunky, being much heavier than most other colubrids of comparable length. They have a sharply upturned snout used for digging and keeled scales. The ground colour is generally buff or tan with darker blotches. The ventral surface (belly) is marked with large areas of black as is the tail. The ventral background colour is tan or buff, but may also include varying amounts of orange. In the Southern hognose snake (Heterodon simus), the belly and tail are both the same colour and lack masses of black pigment. In Eastern hognose (Heterodon platyrhinos), the tail is much lighter than that of the belly. Neonates look like the adults and average 5.5 to 7.75 inches long at hatching.
When first encountered in the field, they will often spread their necks horizontally while hissing loudly. They will also curl their tails, reminiscent of a rattlesnake, and may also strike; but with a closed mouth. The overall stocky, blotched appearance of the hognose snake and the loud hissing and tail curling is thought to mimic the Prairie rattlesnake. The hissing does sound somewhat similar to the rattling of a rattlesnake. If this aggressive bluff does not scare the attacker away, the hognose will suddenly undergo convulsions with much twisting and contorting. The mouth will hang open and the snake will roll belly up as if dead. If the snake is turned over, it will quickly roll onto its back again. This may be due to the fact that many predators will not eat carrion. In captivity, hognose snakes will still hiss and spread their hoods at times, but will usually not perform the death act. However, some hatchlings may exhibit this behaviour.
Western hognose snakes are diurnal (active mostly during the day). They generally occupy prairie and savanna types of habitat; especially areas with dry, well drained soils suitable for digging. The hognose snake's major natural prey consists of toads, frogs, lizards, small snakes, and reptile eggs, but will also take small rodents and birds. These snakes generally do not strike at their prey, but rather chase it down while holding their mouths agape in anticipation! Once grabbed, the prey may be held down with a body coil but these snakes are not constrictors.
Hognose snakes are rear fanged. These fangs are described as being used for the "popping" of toads that are swollen with air (a defensive adaptation of toads and some frogs which is meant to make them look bigger and to make them harder to swallow) similar to popping a balloon with a needle. However, western hognose snakes have been shown to produce mild venom, which seems to be specific to amphibians. A few people have reported mild pain and swelling as a result of being bitten by these snakes, but it is very difficult for the snake to bite a human using these fangs as they are set well back in the snake's mouth. Only a few areas of the adult human body are susceptible to these fangs such as the area between the fingers and finger tips as these snakes are too small to effectively envenomate an arm or hand. In addition, these snakes are generally very well mannered and gentle. If severely provoked, they may strike at a person, but most times they do so with a closed mouth as part of an aggressive bluff act they may perform. Feeding bites are more of a worry, but the snake would have to be allowed to chew on you in order to bring these fangs into position to penetrate a human. Due to the extreme unlikelihood of a person being envenomated, coupled with the mildness of the venom, these snakes are generally considered nonvenomous
Subspecies and Mutations
Plains Hognose Snake (Heterodon nasicus nasicus): This subspecies has distinct dorsal blotches in high contrast with the background colour. Males have greater than 35 dorsal blotches while females have greater than 40 such blotches as measured from snout to just above the vent (cloaca). Colour is usually buff to buff-green with darker brown to olive green blotches. This subspecies ranges from Minnesota to southeast Alberta and south to New Mexico. Isolated colonies also occur in Manitoba and Iowa.
There are two main colour mutations known for the plains hognose snake; a beautiful albino morph and a very nice axanthic morph. Both mutations are single recessive traits. The albino hognoses are yellow with bright orange blotches, while the axanthics are silver with black to gray blotches. Both colour mutations yield very nice looking snakes. A second albino line exists where the snakes are more whitish with pinkish markings.
Dusty Hognose Snake (Heterodon nasicus gloydi): This is separated from the above subspecies mainly by blotch counts. Dorsal blotches in males are less than 32 and less than 37 in females. These dorsal blotches are also in less contrast (usually rather obscure) with the background colour than in the plains hognose. This subspecies ranges from southeast Kansas to most of Texas. Isolated colonies occur in southeast Missouri and southwest Illinois. The dusty hognose integrates commonly with the plains hognose in areas where their ranges overlap. Some gloydi can be very attractive as they contain increased amounts of red coloration.
Mexican Hognose Snake (Heterodon nasicus kennerlyi): This subspecies resembles gloydi in color and pattern, but has less than seven azygous scales while both gloydi and nasicus have greater than nine. This snake ranges from extreme southern Texas and southeast Arizona into northern Mexico. A patternless mutation in Mexican hognoses exists which is called "Blonde".
Vivarium Setup
Minimum Vivarium size for an adult hognose snake would be a 24" long x 12" wide X 12" high, but preferably larger. The glass doors should fit snugly and be made specifically for reptiles as snakes are notorious escape artists. The vivarium requires a temperature gradient in order to allow the snake to regulate its body temperature by moving to either the warm or cool end of the vivarium. There are different ways to achieve a good temperature gradient. One way is to use a heat mat. Place the heat mat under the vivarium, and measure the temperature. This area should be approximately 82F to 85F. Now, measure the temperature at the cool end of the vivarium. This area should be in the high 70's. Use the heat mat in conjunction with a thermostat to control the amount of heat given off. Thermostats measure the temperature inside the vivarium and automatically adjust the heat output of the heating device to maintain the correct temperature. No specific light requirements are needed. However, a fluorescent light will allow you to see your new pet.
Vivarium furnishings can be kept simple. For substrate use newspaper, wood shavings, or cypress mulch. The vivarium will also need a sturdy water bowl large enough for your snake to completely submerse itself in. Snakes will often soak prior to shedding their skin or after eating. A rock large enough to be difficult for the snake to move should also be provided to allow the snake to rub against in starting a shed. Lastly, two hideaways need to be placed in the vivarium: One on the warm side and one on the cool side to allow the snake to feel comfortable when inactive. A good hide away has just enough room for the snake to squeeze into after a meal. The tighter it is the more secure the snake will feel.
Feeding
Western hognose snakes will do very well on a diet consisting solely of domestic rodents. Baby hognose snakes will often start out eating a newborn mouse pink without trouble. If not, then split brain pinks will usually work for their first meal. Sometimes it will be necessary to use toad or frog scented pinks as hognose snakes are voracious amphibian feeders. As the snake grows, you can feed increasingly larger mice. Baby snakes should be fed every 4 to 6 days while adults will do well on fuzzies or dead hoppers fed every 7 to 10 days. The size of the prey item should be no larger than the maximum diameter of the snake. Feed until satiated, feed prekilled prey for hognose snakes as these snakes do not constrict their prey. They will often grab the mouse by a foot or by the rump. If the mouse is a live hopper or larger mouse, the snake will likely be bitten. Hognose snakes do not always take prekilled mice. In these cases, Feed several live fuzzy mice to adults rather than risk a potentially serious rodent bite.
Some owners prefer to buy rodents frozen in bulk to save money, and this can be a very convenient supply of food items. Other keepers prefer to buy live rodents. Rodents can be bred at home, but unless you have a number of snakes to feed this is probably more trouble than it is worth.
Several things can be tried to induce a troublesome neonate to eat its first meal. First, place a newborn mouse pink inside the snakes enclosure overnight. If the snake does not eat it, then take the snake and the pink and place them both in a much smaller container overnight. If this still does not work, give the snake a couple days of rest then try a split brain pink. This involves taking a DEAD pink and cutting into the head to expose the brain. Place the split brain pink and the snake into a small enclosure overnight. This will often work. If not, try a toad or frog scented pink. Thaw a pinky and rinse it with water. Take the pink and rub it against either the vent of the toad or the glands on the side of the head. You can use either a live toad for this, or you can freeze one. Lizards are often used for scenting as well. Cut open the abdominal cavity of a frozen lizard and rub a thawed pink into this cut and place this scented pink and the snake into a mall enclosure overnight. Anoles and house geckos work well. This can also be tried using a small piece of toad, frog or lizard skin dried onto the head of the pinky. These techniques and a lot of patience should get a troublesome hatchling to eat. However, it is the breeder's responsibility to make sure that any snake that they sell is eating unscented mice before selling it.
Another thing that will sometimes work to get a troublesome baby to eat is to try a different food item. If available, a pink deer mouse will often elicit a very strong feeding response in most North American snakes of the genera Lampropeltis, Elaphe, and Pituophis, and may be useful for Heterodon too. Although the information above is a bit frightening and at times gruesome, do not be discouraged as most pet owners will never have to deal with these problems. However, if you intend to breed your snakes then you will need to be familiar with these techniques.
Breeding
Prebreeding Conditioning: Before beginning to breed or brumate your snakes, inspect them closely. They should be in optimal health and have good weight. They should have a minimum size of 16 inches and have good weight. If your snakes are smaller than this or are thin or otherwise not in optimal health, then wait until the following year to breed them. Otherwise, you may end up with a dead snake or experience problems like egg binding. The generally accepted method of breeding hognose snakes involves a period of cooling called brumation which is similar to hibernation but the snakes still remain active to some extent. This involves first stopping feeding two weeks before the cooling period is to begin. This is to eliminate any remaining food still inside the snake, which could rot inside the snake during cooling and potentially kill it. After the two weeks are over, slowly decrease the temperature over several days until a temperature of about 55F to 60F is reached. Keep the snakes at this temperature for two to three months usually from December through February. Check on the snake's health frequently, and change their water weekly. If any signs of respiratory infections are seen, then warm the snake up and treat the infection. Do not feed the snakes during this time. At the end of the cooling period, slowly warm the snakes up to the normal maintenance temperatures and begin feeding. Feed the females as much as they will eat in order to fatten them up before breeding.
Breeding: After her first or sometimes second shed, the female will be ready to breed. Start to introduce the female into the male's cage. Watch the pair closely, if the female is ready for breeding she will produce pheromones from her skin which will attract the male. The male will start to chase the female and rub his "chin" along her back. Actual breeding usually lasts about 20 minutes or so, but could last an hour or more. If they do not breed after an hour or two, separate them and try again in a day or two. If they do breed, then separate them afterward and reintroduce them every couple of days until she has been bred at least three times. This should ensure the fertility of the eggs. After the female has been bred, again start an accelerated feeding schedule. Feed the female smaller, easily digested food items every few days. She will need these nutrient reserves to produce the eggs. About six weeks after breeding, the female will undergo a shed cycle. At this time you will need to give her a nest box to lay her eggs in. This box should contain moist but not wet sphagnum moss in a closed dark container. Use plastic storage box with a hole cut in the lid. Remember to cut the hole larger than normal, as she will be swollen with eggs. About 10 days after shedding, the female will become very active as she searches for the best place to lay her eggs. She will usually settle down inside the nest box and lay her eggs, from 5 to 30 depending on the size of the female, sometime over the next couple of days. If she settles into the water dish, you may want to replace it with one that is too small for her to enter and without a lid. This will encourage her to look for another place to lay her eggs. After she lays her eggs, feed her a smaller than normal prey item for the next couple of feedings. She will be weak from her pregnancy and small prey items will be easier for her to eat and digest. If a second mating and egg clutch are to be attempted, than again feed her on the accelerated feeding schedule. After her next shed, start to reintroduce the male as before. Remember though that a second clutch of fertile eggs is possible without a second breeding due to stored sperm. After the second clutch is laid, it will be even more important for the female to regain her lost weight. Feed her as much as she will eat until she has regained good weight
Care for the eggs and babies: The eggs should be placed inside a container (plastic food containers without the lid work well) of coarse, damp vermiculite. The vermiculite should be mixed with water 1:1 by weight. This should make the vermiculite damp enough to just clump when squeezed together. The container should then be placed inside an incubator of some kind that will maintain a temperature of around 82F. Watch the eggs closely, if they begin to dimple or cave in, then add a little more water. The eggs should hatch in 6 to 8 weeks.
When the eggs start to hatch, the baby (neonate) snake will slit open the leathery egg by means of a temporary egg tooth located on the tip of their snouts. They will often remain inside the slit egg for a day or two with just their heads sticking out of the slit. Do NOT try to force the baby out of its egg before it is ready, as it will be attached to an umbilicus and yolk sac. Forcing it out of its protective egg may result in killing the snake due to dehydration as water will be quickly lost through the yolk sac and umbilicus. Also, do not cut the umbilicus as it will cause the snake to bleed to death. The umbilicus will fall off on its own in a day or two so wait until the snake leaves its egg on its own. Set up each neonate into its own separate enclosure. Use plastic boxes with many very small holes drilled into all the sides. Use paper towels as substrate and keep careful records of sheds and feedings. Unlike most other North American snakes, the baby hognoses will usually shed their skin the same day they hatch. The baby snakes will usually start eating sometime over the next week or so. Start them off on a live newborn pink mouse, but they may want a toad scented mouse or a split brain pink mouse for there first feeding. Baby hognose snakes can be fairly reliably sexed by tail length, especially if you have a number of snakes to look at. The males have a much longer tail than do the females. Take two babies and hold them together such that their vents are lined up. The tails of male babies will be around 25% longer than females. Popping is usually done to confirm sex determination by tail length, but often is not necessary.
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