Rubber Boa

Charina bottae

Rubber Boa. Photo:David Green

The only member of the family Boidae in Canada, this "little" 73 centimetre boa contrasts greatly with the other more highly publicized members, like the anaconda, the boa constrictor and the pythons, all reaching up to or over 6 meters in length. Like its larger relatives, the rubber boa also kills its prey by constriction. This involves squeezing prey so that it is unable to inhale, and with each exhalation, the snake tightens its grip a little more so that eventually, the prey's chest can no longer expand to take in air and it quickly suffocates. This method of killing its food is particularly well suited to this snake's diet, considering its prey typically have sharp beaks, or claws and teeth. Wrapping its body around the animal thus prevents the hunted from bringing its potent defenses to bear against the hunter. Typically slow and sluggish compared with other snakes, the secretive and nocturnal rubber boa is nevertheless a competent burrower, swimmer and climber, performing either with ease. This range of talents serves it well in the wild, as its range extends through grasslands and forests, interspersed with brooks, streams and ponds. Its name of rubber boa comes from the fact that its smooth scales and wrinkly skin give it a rubbery appearance. Because of its habit of rolling into a ball with its featureless head tucked in and its blunt tail sticking out, the rubber boa has acquired another common name, that of "two-headed snake". Like other members of the Boidae, it retains a vestige of a pelvic girdle and hind limbs, little more than tiny claws on its "flanks". These are larger in males and serve a role during courtship, which if successful, eventually results in liveborn young.

Distribution of Rubber Boa in Canada