There are a lot of snakes that fall within the group of colubrids. Below is some information on all of the colubrids, broken down into basic info and then more specific info on the different types of snakes.
The colubrid snakes are a widespread and common group of serpents found around the world. Of these, a few of the constricting species, such as the corn, rat, king, bull, pine, and gopher snakes, are the most popular pet reptiles on today's market. There is a reason for this - these snakes make great pets. They are calm, docile, stay reasonably sized, and are generally easy to take care of. This, in addition to the fine qualities of any pet snake - quiet, low maintenance, non-allergenic, essentially no odor, and no mess outside its cage.
A few of the colubrids are venomous, but all of the constricting colubrids are completely harmless. Even if they bite you, their teeth will not do much more than leave a series of tiny puncture marks. It probably will not even hurt, although it may surprise you. They are far too small to pose a danger to a human by constricting.
These snakes are easy to keep. Most species will do fine in a 20 gallon glass terrarium as adults, although the larger gopher, pine, and bull snakes may need 30, 40, or 50 gallon cages. Whatever size cage you need, make sure it has a top that fits snugly and securely, and preferably one that locks in place. Snakes are excellent escape artists, and a loose lid means you will soon have a missing pet. It is best not to rely on heavy objects to weigh the lid down. These constrictors are very powerfully muscled and many will be able to push off seemingly adequate weights. Of even more danger is the possibility that another member of the household, possibly a cat, dog, a child, or an inattentive adult, will knock the weights off, and the snake will be able to escape.
Most any substrate can be used as long as it is easily changed and will absorb the fluids produced when the snake defecates. Simple stuff, like newspaper, paper towels, or butcher paper is fine, as is Care Fresh, most barks, and most wood shavings. If you use wood shavings, it is best not to feed the snake in its cage, as the shavings may catch on food items and be partially or wholly injested. Substrates to avoid include cedar (in any form), which contains oils that are toxic and can cause skin lesions, and corn cob bedding, which will swell if ingested and can cause intestinal blockages.
The snake should have a place to hide, a spot where it can securely curl up away from prying eyes. A piece of bark placed on the substrate will work, or a box with a hole cut in it just large enough for the snake to completely fit into. A water dish is necessary, and it is best if the snake can curl up and soak itself in it. Other "cage furniture" can be added as desired. The corn and rat snakes in particular may appreciate a branch to climb on, although this last touch is certainly not necessary.
It is important to establish a proper thermal gradient in the cage. One side should be kept at around room temperature (15 to 25 degrees C), the other should be heated to around 30 degrees C. You can heat the hot side by using an under tank heating pad, an electric heating strip, a medical heating pad, an incandescent light bulb, or a ceramic heater. Make sure the snake does not get too hot, snakes can tolerate cool temperatures better than excessively hot temperatures, so always make sure the snake has a place to cool down. Do not use "hot rock" type heaters. These products can (and often do) dangerously overheat and burn your snake.
Special lighting is not really necessary for your pet snake. Although many reptiles need ultraviolet B light to properly metabolize calcium, most snakes (including all the common constricting colubrids in the pet trade) do not. Broad spectrum lighting can help make an attractive display, and will bring out your pet's colors, but is not neccessary for its health.
Feeding these snakes is usually very easy. Place a previously frozen and defrosted mouse in its cage, and most snakes will happily chow down. For the larger bull, gopher and pine snakes, you might want to feed various sizes of rats rather than mice. These snakes can be fed once a week or so. It's important to not allow too much outside stimulation (movement, staring at the snake, visually challenging things) or your snake might not focus on its meal.
Occasionally, however, you may get a pet that gives extra trouble when it comes to the eating department. Young corn, rat, and kingsnakes will sometimes refuse young mice. These snakes can usually be enticed into eating by offering them a treefrog or small lizard such as a young house gecko or anole. These food items are not commonly available for most people, and are generally more expensive and less convenient than frozen mice. You can try various tricks to get a baby to eat mice, such as by rubbing a mouse with a lizard or frog. Other times you get adults (most notably with kingsnakes) that refuse to eat mice, but that will happily eat chicks, lizards, frogs, or maybe only snakes. If you cannot switch these to mice, you will probably have to live with a pet that has expensive dietary preferences. Another problem occasionally encountered is a snake that refuses to eat pre-killed prey. Sometimes these will eat freshly killed food. This is far preferable to feeding live food. Although snakes are powerful predators and can kill a mouse without problems just about every time, sometimes the mouse gets lucky and will deliver a bad bite to the snake. Rodents leave deep bites that can easily become infected. If your snake will only eat food that is still alive and kicking, supervise it while live prey is in its cage. If the snake hasn't eaten in a few minutes, it is probably not hungry, so remove the mouse and try again later. Leaving a rodent in with a snake unsupervised is generally a bad idea. A fear or hunger crazed rodent may attack your pet. When snakes are not in a feeding mode, they will not attack the rodent to kill, and the rodent can deliver terrible wounds to your snake.
Sometimes, a snake will simply go off feed for a while. As long as it is in reasonably good weight, this is not usually a problem. Snakes can fast for several months, sometimes even more than a year, without ill effects. Many times, they begin to fast in the winter, and will not feed again until spring. In this case, you may want to "hibernate" your pet. Simply turn off its heat and drop its temperature down to 5 to 10 degrees C. It is important not to let the temperature fall below freezing, as this will kill your pet. When springtime comes around, you can warm your pet back up again, and is should be eager to feed.
Every so often, your snake will shed its skin. Adults may shed once every several months, young and growing snakes shed more frequently. For a week or so before shedding, its eyes will turn blueish colored and cloudy. The snake will usually be uninterested in eating, and may be more irritable than usual. When it is time, the snake will start rubbing its nose against its cage furnishings, the skin will start to peel back, and the snake will simply crawl out of its old skin. The skin comes off inside out, like when you pull off a sock. When freshly shed, your snake will be extra shiney and colorful. Occasionally, a snake will have trouble shedding, usually because the humidity is too low. If the skin is not all coming off, you can let the snake soak, or even force it to soak, and then try to help it by rubbing its stuck-on skin off with your fingers. **Special note, please make sure that the snake does shed it's eye caps. If the eye caps do not come off, following sheds may result in the caps becoming stuck and may lead to blindness. This can be surgically assisted, but can be risky and quite costly, if you are lucky enough to find a veterinarian in your area that is experience in reptiles, that you trust.
Corn snakes are one of the most common of the colubrids kept as pets. The wild form is attractively marked with red, dark brown, and white. In captivity, however, many color mutations have been found and propagated, so that today it is often difficult to find the wild pattern in pet stores. Corn snakes rarely get more than 1.5 meters in length, and stay slender.
The corn snake is just one member of the rat snake family. These snakes are excellent climbers, and will grip your hand securely with their body or tail when held. In the wild, they eat small mammals, birds, small lizards, and frogs. They are particularly adept at climbing trees to raid bird nests. Other rat snakes occasionally found in the pet trade include black rat snakes, Texas rat snakes, and yellow rat snakes.
The many subspecies of the common kingsnake is probably the second most popular group of snakes in the pet trade, after the corn snake. Of these, the California kingsnake is probably the most commonly seen. Like the corn snake, breeders have found many color and pattern mutations, so now kingsnakes come in all sorts of eye popping colors. Wild common kingsnakes are typically dark colored with light colored rings or chain patterns. They eat small mammals, birds, lizards, frogs and other snakes. This last item on their diet give kingsnakes one extra worry for their owners - they must be kept separate from all other pet snakes. House no more than one kingsnake to a cage, or you may end up with just one big, happy kingsnake in that cage anyway. Wild kingsnakes are famous for eating rattlesnakes, since, apparently, the kingsnakes are immune to rattlesnake venom.
Kingsnakes other than the common kingsnake are also common in the pet trade. There are many tri-colored king snakes available. These coral snake mimics are vividly colored with red, yellow, and black rings. The grey banded kingsnake is also sometimes found for sale, and has something of a cult following among its keepers, who often pursue the breeding of animals they collected from specific localities.
The bull, gopher and pine snakes are a group of closely related large snakes who specialize in eating rodents. In the wild they will also eat birds and their eggs, but they are famous for their ability to consume huge numbers of pestiferous rodents that threaten farmer's grain supplies. These are among the largest snakes in North America, getting close to three meters in length for the really big bull and pine snakes. In captivity, they are famous for their voracious appetites; bull, pine, and gopher snakes rarely refuse food, and they will happily eat many rodents at one sitting. When scared, most constricting colubrids will vibrate their tail, an act that can make them sound like a rattlesnake if the tail is in dry leaves or grass or up against hard rocks, but the bull, pine and gopher snakes take this mimicry to a whole new level. They have a coloration and pattern that closely resembles that of the rattlesnakes, and when disturbed they will coil and strike like an angry rattler, while flattening their head to mimic the triangular head of a rattlesnake. The bull snakes also have a hiss that sounds very close to the rattle of a rattlesnake. All of this may help them fend off coyotes or racoons, but winds up getting many of these magnificent, harmless, and beneficial animals killed by humans who cannot tell the difference. In captivity, the bull, pine, and gopher snakes usually quickly tame down, and once that happens, it is almost impossible to get them to display their rattlesnake act for you.