Northern Rubber Boa
Charina bottae • Order: Squamata, Suborder: Serpentes, Family: Boidae, Subfamily: Erycinae, Genus: Charina, Species: Charina bottae
Western North America, spanning from southern British Columbia in Canada, south through Washington, Oregon, Idaho, western Montana, Wyoming, Nevada, Utah, and California in the United States.
Look up Northern Rubber Boa in the Snake Encyclopedia →Family
Order: Squamata, Suborder: Serpentes, Family: Boidae, Subfamily: Erycinae, Genus: Charina, Species: Charina bottae
Conservation
IUCN Red List status is Least Concern. Populations are generally stable, though localized habitat destruction, climate change, and forest management practices pose potential threats.
Physical Description
Characteristics include extremely smooth, small, shiny dorsal scales that give the skin a rubbery look and texture. Coloration is uniform tan, olive, brown, or grayish-brown dorsally, with a pale yellowish or cream-colored belly. The head is blunt and indistinct from the neck, with small eyes featuring vertical pupils. The tail is short, thick, and blunt, closely mimicking the shape of the head.
Size & Dimensions
This specimen appears to be an adult measuring approximately 40 to 50 cm (16-20 inches) in length. Typical adults range from 35 to 84 cm (14 to 33 inches) in total length, with females generally growing larger than males.
Habitat
Fossorial and terrestrial snake found in a wide range of habitats from sea level up to around 3,000 meters (10,000 feet) in elevation. Common habitats include coniferous forests, open woodlands, chaparral, grasslands, and rocky stream banks. They prefer damp microhabitats under rotting logs, flat rocks, and loose soil.
Diet & Feeding
Primarily feeds on small mammals such as young mice, voles, and shrews, as well as lizard eggs, small lizards, and occasionally other snakes. Uses active foraging and constriction to subdues prey.
Reproduction
Viviparous (gives live birth). Females give birth to litters of 2 to 8 young typically in late summer or early autumn (August through October). Females reproduce every two to three years depending on resource availability and thermal conditions.
Look-alikes
Often confused with the Southern Rubber Boa (Charina umbratica), which is smaller and restricted to isolated mountain ranges in Southern California. Also superficially resembles legless lizards (like the Northern Alligator Lizard) or juvenile racer/garter snakes, but distinguished by its smooth rubbery skin, blunt tail, small eyes, and uniform dorsal coloration.
Conservation Status
IUCN Red List status is Least Concern. Populations are generally stable, though localized habitat destruction, climate change, and forest management practices pose potential threats.
Cultural Significance
Plays an important ecological role as a mesopredator controlling rodent populations in western forest ecosystems. Often referred to as 'the double-headed snake' by locals due to its blunt tail.
Notable Features
Famous for its remarkably loose, rubbery skin and blunt, rounded tail that resembles its head. When threatened, it often coils into a ball and raises its tail to distract predators away from its actual head, frequently resulting in scarred or blunt tail tips from predator attacks.