Crotalus ravus

Image Credit : Matthieu Berroneau

Crotalus ravus is a small sized venomous pit viper species. There are 3 described subspecies, C.r.ravus, C.r.brunneus and C.r.exiguus.

The basic coloration of Crotalus ravus is usually brown or gray with a drawing of dark or rust brown spots on the back, which are bordered by narrow black scaly rows and are usually brighter to the center. The head is unmarked and on the neck there is a striking patch.

  • Scientific name : Crotalus ravus
  • Distribution : Mexico (Puebla, Veracruz, Morelos, Tlaxcala, Guerrero, Oaxaca, Hidalgo)
  • Average Size : 0.5 m (1.6 ft)
  • Life Span : 12 years or more
  • Difficulty : Advanced


Crotalus ravus are small species so large housing is not that necessary. An enclosure of 0.9 meters long, 0.45 meters width and 0.45 meters high (3 x 1.5 x 1.5 feet) is considered as appropriate. A slide-door or Lanzo type terrarium is a good choice for this species.

Hide box

This species prefer large and dark hideaways so you can use paperboard boxes or large tree bark as an example. I keep one hide spot on the cold side of the enclosure.


You can choose between a big variety of substrates such as aspen, tree bark (small), peat moss and coconut fiber but you should avoid using sand or garden dirt as they can get dusty and can damage the snake’s respiratory tract. My personal recommendation would be a mix of peat moss and tree bark with leaf litter on top.

Lighting – Heating

Crotalus ravus is a high mountain species so it depends on the place you live if you’re using extra heating or not. Temps should be between 23-27 °C (73-80 °F) during the day and around 18 °C (64 °F) at night. If you live in a very cold place you can help yourself using a spotlight or a thermal plate so that temps will never drop under 16 °C (60 °F).
My light cycles are different according to the season. For late half of fall – winter I keep 8/16 hours (day/night) and for spring – summer – first half of fall I keep 12/12 hours (day/night). This will work for both breeding and maintenance purposes.


Always keep clean water in a large container but not too tall. It’s a good practice to change the water every 2-3 days or whenever the snake defecates in the water bowl.


I keep my Crotalus ravus at the humidity level of 60-80%.


Crotalus ravus feed primarily on mice. Prey must be offered according to the snake’s size. Some herpetologists say that they feed on insects as neonates but I have never seen that personally since I have always fed these snakes with mice and never encountered any major problem.
I feed my juveniles once a week and my adults every 2 weeks.


Crotalus ravus are usually easy to handle compared to other species. They tend to be calm and easy going when lifted with hooks but of course that’s not always the case so you should always be careful. No tongs are needed even with the most aggressive individuals. Use of tubes must be only for medical purposes such as probe test, tube-feeding or applying drugs.


Depends on the type of substrate you are using. If using peat moss, coconut fiber, tree bark or aspen, spot cleaning of feces will work but try to change the whole substrate every 1 or 2 months (depending on the size of the enclosure). If using newspaper you must change it every week.


They shed their skin 2-6 months, depending on the age and size. During shedding period is recommended to raise the humidity a bit.

Potential Health Problems

No specific potential health problems to mention for this species beyond those affecting reptiles and/or snakes in general. They seem to be a relatively hardy animal when kept properly.

Bite Protocol

It’s highly recommended for every venomous species that you keep or interested to keep to have the bite protocol. Each species has a dedicated bite protocol that includes general information regarding the species, information about their venom and signs and symptoms of envenomation if bitten. It also includes a detailed information about first aid (what to do and what not to do), specific treatment recommendations for medical personnel to provide appropriate care including information about the antivenom or antivenoms required for treatment. Finally it includes a list of people who specialize in snakebites and their contact information so they can be consulted to assist with the care if needed and a list of all the references used for the create the protocol.

Recommended Book


Zlayer Drawhold

The information contained in this care sheet reflect the opinions and methods of the mentioned breeder, based on their expertise and long-established experience.