Common Name(s): Bull Snake
Latin Name: Pituophis catenifer sayi
Ease of Care: Moderate
Native To: Southern Canada, Central United States, and Northern Mexico
Adult Size: 5-7 feet
Life Span: 15-20 years
Clutch Size: 10-16 eggs
Appearance: Bull snakes are quite interesting looking and impressive Colubrids, with most having a cream colored background with brown or reddish-brown blotches along their backs. Their appearance and coloration can very quite a bit within different localities and ranges depending on what color the soil is so that they have a better natural camouflage. Bulls grow quite large for a colubrid with most maxing out around 6.5 feet and some growing larger. They are often confused with their cousins in the Pituophis genus, the gopher snake and the pine snake and it can take a good eye to see the general differences between these snakes.
Temperament: This is why we’ve given this snake a “moderate” rating. Bull snakes are known for their ability to let out a very loud and intimidating hiss as a defensive measure and it can be quite off-setting to most first-time owners. They can be very quick, hyperactive snakes as juveniles, but tend to calm down with age and proper handling. We always try to be weary of our bulls and give them the respect they deserve. These are great snakes for MOST people, and make great pets with the proper amount of gentle human interaction and attention.
In The Wild: In the wild this fossorial species spends most of its time in burrows and has developed a truly impressive way of digging. Bull snakes tend to live in areas with shortgrasses or prairie lands that have loose soil that is easy to dig in. Once they find a place for a burrow, they will dig in with their snout and hook the loose dirt with their neck and pull it back out of the hole. It is truly amazing to see in the wild, and we suggest you try and do a quick search on YouTube to find this awesome behavior. Other than being fossorial, Bull snakes are solitary creatures, like almost all snakes, and tend to move between different burrows of the small mammals that they hunt in the wild. Bull snakes feed on small mammals, birds, lizards, and even other snakes in the wild and younger snakes will be semi-insectivorous as well. They breed in the early spring months after they have emerged from brumation, and eggs will normally hatch in mid-July and August, giving the newborns a few months to feed before they go back into brumation again.
Caging: Bull snakes are on the larger side of the colubrids, and are fossorial snakes that require a sufficient amount of floor space in order to remain comfortable. Most breeders will keep Bulls in rack systems that utilize tubs approximately the size of the larger under-bed tubs that you can buy at a Target or a Bed, Bath, and Beyond. We like to use display cages that are approximately 4’x2’x2’ and find that this gives our Bull snake plenty of room to move around and find a good temperature gradient across the cage. The bedding should be loose enough that the snake can burrow. We suggest using aspen, coconut husk, or ground walnut shells with our favorite being the ground walnut shells. This medium is loose enough for the snake and doesn’t absorb the moisture that coconut husk is known to absorb and maintain. These snakes need drier conditions to make sure that blisters or other skin infections don’t occur due to too much moisture.
Lighting: No special lighting is required, although it has been shown that lighting cycles that mimic the normal sunlight hours of the different seasons (shorter hours in the winters, longer in the summers) can be beneficial when trying create breeding cycles for your snakes. But, since these snakes are mostly fossorial and crepuscular, a UVB lighting system is not needed but can be used for your pet Bull snake.
Temperature & Humidity: Another reason why Bull Snakes can be such great pets for most people is because of their ability to handle semi-fluctuating temperature and humidity conditions. The ideal conditions for your Bull snake are to have a hot side and cool side of the cage with a floor temperature of 85-87F on the hot side and 75-78F on the cool side during the day. The cage temperature can be maintained with heating pads, heat tape, or bulbs but should be measured continuously to make sure the proper heating gradient is being maintained. We suggest using heat tape under the cage, coupled with a thermostat for heat regulation. This temperature differential allows the snake to choose a comfortable set point to regulate it body temperature. At night, a 5-degree temperature drop on both sides is best. Finally, humidity levels should hover right around the normal levels of a home (40-55%) and should be monitored as well to make sure the snake doesn’t develop a skin irritation or respiratory infection from being in too humid an environment. These levels should be elevated, however, or a shed box that is more humid should be provided for the snake as it goes in to shed in order to make sure the snake sheds correctly and remains healthy.
Feeding: As always, we recommend that you feed your Bull snakes frozen-thawed food items in order to make sure that the snake is not harmed while feeding or that if the snake is uninterested in the food item, that the mouse or rat does not chew on the snake. We also suggest that the rule-of-thumb be followed to offer your Bull snake a food item that is no more than 125% the width of the snake’s body at its widest place. This normally means feeding fuzzy or hopper mice for younger snakes and medium rats for adults. We feed our babies every 4-5 days and adults every 7-10 to maintain a healthy girth and length. Following these general rules will keep your snake healthy and its growth at a standard, healthy rate.
Sexing: Sexing Bull snakes is much like any other snake and there are many different ways to sex your snake, but the only 100% reliably way is to have somebody who knows what they’re doing probe the snake. Other ways to sex the snake include the length of the tail with males having longer, thicker tails from vent to tip in order to store the inverted hemipenes that are absent in females. Females will have a shorter, more quickly tapered tail than males. Another way to sex young Bulls, and this should be performed by somebody who knows what they’re doing in order to make sure the snake is unharmed, is to “pop” the snake in order to invert the hemipenes on a male or nothing on the female. This method is used by most breeders for young bulls, and the tail length method is normally used for adults. But, as stated at the beginning, probing is the only 100% reliable way to sex any snake.
Breeding: Breeding Bull snakes is a very much like breeding any North American Colubrid, and very rewarding endeavor for any Bull snake owner. Bulls normally reach sexual maturity by their 2nd year. When the snakes are at sexual maturity, it is safe to breed the females by putting them through a full breeding season. The most important parts of the breeding process include brumation which is the period during the fall and winter months that a artificial winter is created for the snakes by lowering the temperature and shortening the daylight cycles to put the snakes in to a brumating state much like hibernation. The snakes should not be fed during this period and should be eased into brumation by dropping the daytime and nighttime temperatures slowly over the course of about a month and taking the snakes off of their feeding cycle in order to insure that the snakes don’t have undigested food that could rot in their stomachs. Brumation should last for about 2 months before the snakes are slowly brought out of brumation by raising the temperature and lengthening the daylight period over the course of two weeks. The snakes should then be fed a few food items before they go into their first post-brumation shed. After the shed, the males should be introduced to the females’ cages for mating over the course of a few weeks. This can be a very exciting time and there are few thing more interesting to a snake owner than watching the courting rituals of these beautiful animals and seeing them lock up to produce the next generation. After pairings have occurred over about 2 weeks, the males should be removed and continue to feed the animals weekly as normal. Some snakes will refuse to eat during this time and this is not uncommon, so don’t stress too much about it if your snakes don’t eat during the breeding season. If a female has been fertilized she will go into a pre-lay shed approximately 2 weeks after copulation and you should be able to see the ovum’s developing towards the rear half of her body. When she goes into this pre-lay shed, we normally like to put a plastic shoebox full of damp sphagnum moss in her cage with a hole cut in the front of it to allow her to enter and leave the box. She should lay her eggs in here and it is good to check her cage every 1-2 days to make sure you don’t miss the eggs. After the eggs are discovered, it is best to remove the eggs gently, making sure you don’t roll them or flip them because the snake inside can drown based on the orientation of the egg. We like to place a pencil mark on the top of the eggs to let us know which side is up. After the eggs are removed safely, they can be carefully separated and placed in a lidded container filled approximately 2/3 of the way with Hatchrite, Vermiculite, or Sphagnum moss medium that is damp enough to keep the eggs hydrated, but not so damp that mold will grow on the outside of the eggs. At this point, some people use a incubator to keep the eggs at the proper temperature, but our favorite and most reliable way is to find a dark, warm corner of a closet and place the eggs here. The temperatures need to remain in the upper 70s or lower 80s for proper egg development. The eggs should hatch in approximately 10 weeks depending on the incubation temperatures, bringing the next beautiful generation of Bulls into the world!
Care of Young: Young Bull snakes can be kept at conditions very similar to adults. Always provide fresh water and a hide for the young snakes, and keep the cage temperatures at approximately 85 on the warm side and 75 on the cool side. We recommend using a shoe-box sized tub in a rack system for newborn Bull snakes, and maintaining a 4-5 day feeding regiment after the snakes cycle through their first shed. Caring for newborns is a busy and fulfilling task, but care should be taken to make sure their conditions are maintained at a stricter level than adults, and snakes should always have eaten 2-3 meals before being sold into the snake trade if that is your ultimate goal with your newborn snakes. If you’re keeping them or raising your first, you should always move the snake up to a larger cage as is grows to give it ample room to move around and exercise, and make sure you increase the size of their food item as needed for each snake.
We hope that we’ve helped you get a good initial grasp on what it means to care for these awesome animals! We have fallen in love with this species, and although they may not be for everybody, these impressive snakes are awesome and we are more than happy to help you make the decision on what snake is best for you. If you have any further questions, comments, or caught something in here you’d like explained or you don’t agree with, please feel free to contact us at our Contact Page. Thanks and Enjoy!