Charina bottae, the rubber boa, is the smaller of the two species of boas native to the United States. It can mostly be found in the Western United States from Washington to California.
Rubber boas have a smooth skin with small scutes. The skin is often wrinkled and loose giving the impression of a rubber tube, hence its common name. One of the most recognizable characteristis of the rubber boa is its blunt tail that looks similar to its head. Rubber boas have a quite uniqe appearance and are rarely confused with other snake species that occur in the Western United States.
Compared to its international relatives, the rubber boa is a comparably small boa. An adult specimen reaches a length of 15-30 inches (40-80 cm). It is slightly smaller than the rosy boa, the only other boa species found in the U.S.
The body of rubber boas is mostly unicolored. Sometimes, they have several darker spots without a specific pattern. The main colors of the upper side are typically dark brown, olive-green or even orange or yellow. The bottom side of the body is unicolored in a lighter color, often yellow or orange.
Ruber boas use two different hunting behaviors. If they are preying on small mammals such as mice, they constrict their prey by wrapping their body around them and soffocate them. In addition to adult rodents, they also feed on eggs or the offspring of reptiles and other snake species. In this case, they use their tail to fend off the mother who is trying to protect its offspring while eating them alive. Adult rubber boas often have numerous scars on their tail from such encounters with lizards.
Rubber boas are nonvenomous and one of the most docile snake species in the world. Even if they are threatened, they never bite humans or appear aggressive. Thanks to this characteristic, rubber boas are often used to help people overcome their fear of snakes. When they feel threatened, however, the sometimes release a very strong smelling-substance to deter attackers. Rubber boas post absolutely no threat to humans or pets.
Charina bottae can live and thrive in a wide variety of habitats. They occur anywhere from sea level to mountainous areas up to 10,000 feet a.s.l. (3,000 meters). They spend a large portion of their lives in hiding in cracks of rocks or similar spots. Therefore, they need a habitat that can support this behavior. Generally, rubber boas are less heat resistant than other snake species. They can rarely be found in very hot environments. Most often, they are found in forest areas, rocky, moutainous areas as well as in grasslands.
Rubber boa range in the USA
The range of the rubber boa stretches along the Western United States from south of Los Angeles in California up to British Columbia in Canada. The fact that it can be found so far up north makes the rubber boa the most northerly boa species in the world. It can be found in these states of the United States: California, Oregon, Washington, Nevada, Utah, Wyoming, Montana, Eastern Colorado and Idaho.
Scientific classification of Charina bottae
- Kingdom: Animalia
- Phylum: Chordata
- Class: Reptilia
- Order: Squamata
- Suborder: Serpentes
- Family: Boidae
- Genus: Charina
- Species: Charina bottae
Other common names
Next to its most popular common name “rubber boa”, Charina bottae is also known under the common names coastal rubber boa, northern rubber boa and two-headed snake.