Sonoran Desert Sidewinder

Crotalus cerastes cercobombus 

By Kris Haas

Introduction: Crotalus cerastes is a small desert dwelling rattlesnake indigenous to arid regions of California, Nevada, Arizona, Utah and northern Mexico. There are currently 3 subspecies of C. cerastes: C. cerastes cerastes, C. cerastes cercombombus and C. cerastes lateropens. Unique among rattlesnakes for their method of locomotion (sidewinding), C. cerastes also possess an orbital “horn” above each eye. Natural prey include small desert rodents, desert lizards and (at least in neonates and juveniles) insects.

Caging: Single C. cerastes can live their entire lives in an enclosure the equivalent of a 10 gallon aquarium. For safety concerns, one should not use a glass enclosure, instead opting for a (lockable) wooden enclosure. For enclosures containing 2 C. cerastes, an appropriate size would be approximately 20 gallons. For 3, try an enclosure 40 gallons or so. Again, it is stressed here that ALL enclosures containing C. cerastes should be lockable. This is a basic prerequisite to keeping any venomous reptile. I have had success in keeping C. cerastes in both individual and group enclosures.

Environmental conditions:   Substrate: I keep C. cerastes on a substrate of sand. The sand should be of sufficient depth so as to allow the snake to “pancake” and borrow beneath it. Hidespot: For individual C. cerastes, a single section of PVC pipe cut length-wise and partially buried in the sand will afford the snake a secure hidespot, as it simulates natural burrows that the snake uses in the wild. One may also find success using a section of corkbark to the same effect with one possible benefit being a more “naturalistic” looking enclosure. For enclosures containing multiple (2 or 3 C. cerastes) one can utilize multiple sections of PVC pipe or corkbark. Humidity: Many errors in the keeping of C. cerastes revolve around humidity. Native to an arid environment, many keepers mistakenly believe that the enclosure should be kept as xeric as possible. While this may be true for the exterior, the burrow (PVC pipe or corkbark) should be kept quite a bit more humid than the rest of the enclosure. I keep my hidespots at approximately 60-65% humidity. In the wild, natural burrows are quite a bit more humid than the external environment, and any enclosure housing C. cerastes should reflect this. Temperature: A thermal gradient should be offered, with the warm end of the enclosure in the high 80’s (F) to low 90’s (F) and the cool end in the low to mid 70’s (F). The keeper may find it easier to maintain humidity on the cool end, and therefore the hidespot may be located there. However, one can also include a hidespot on both ends, and allow the snake to choose which one to utilize.

Feeding: In captivity, many C. cerastes will accept either live or pre-killed mice as food. Freshly wild-caught cerastes may initially refuse them, or refuse food altogether. One should always give a newly acquired C. cerastes a “settling in” period, and the snake should be disturbed as little as possible. I have had success getting newly captured cerastes to eat by “scenting” mice with small desert lizards (i.e. Coleonyx). One can take a Coleonyx tail (they will shed them when frightened) and smear some blood on the head of a small mouse. One may find it beneficial to wash the mouse first. I have also had success in “scenting” a washed mouse with a gerbil, as the gerbil more closely smells like the snake’s natural prey. If one is to attempt to feed live prey (not recommended unless the snake will not accept anything else) one must observe the interaction between the snake and prey item in order to avoid injury or death to the snake. One can simulate a live prey item by teasing the snake with the dead mouse utilizing a pair of metal hemostats. Pressed enough, the snake will likely strike at the prey item, thus eliciting a feeding response in most cases. Juvenile cerastes can be difficult to get feeding. One can try the above methods, using a mouse pinkie (or pinkie parts for small neonates). “Braining” mouse pinks has also worked in some cases with stubborn jeveniles and neonates. When possible, it is advisable to get captive cerastes to feed on rodents, as these are much easier (and less expensive) for most keepers to acquire than are lizards. Assuming that the enclosure is set up correctly, most cerastes that I have kept have eventually begun to feed on pre-killed mice on their own, with minimal teasing on my part.

Venom: While generally considered “less dangerous” than many of its larger kin (due to a low venom yield), C. cerastes still has a dangerous bite and should be respected as any venomous snake would be. While fatalities from a cerastes bite are almost unheard of, bites can result in the crippling of fingers and other extremities, and in rare cases amputation becomes necessary. One should never take undue liberties with this species due to its small stature. Treat this snake as you would any other rattlesnake!