Description: Rubber boas are one of the smaller boa species, adults can be anywhere from 1.25 to 2.76 feet long; newborns are typically 7.5 to 9.1 inches long. The common name is derived from their skin which is often loose and wrinkled and consists of small scales that are smooth and shiny. These characteristics give the snakes a rubber-like look and texture. Colors are typically tan to dark brown with a lighter ventral surface but sometimes olive-green, yellow, or orange. Newborns often appear pink and slightly transparent but darken with age. Rubber boas have small eyes with vertically elliptical pupils and short blunt heads that are no wider than the body. One of the most identifiable characteristics of rubber boas is their short blunt tails that closely resemble the shape of their head. Rubber boas appear quite different visually than any other species that share the same range (except maybe for the southern rubber boa) and thus are usually easy to identify.

Habitat: Rubber boas have been known to inhabit a wide variety of habitat types from grassland, meadows and chaparral to deciduous and conifer forests, to high alpine settings. They can be found at elevations anywhere from sea level to over 10,000 feet. They are not as tolerant of higher temperatures as other snake species and cannot inhabit areas that are too hot and dry, but can live in areas that are surprisingly cold, especially for a snake. Rubber boas also spend a large amount of time under shelter (rocks, logs, leaf litter, burrows, etc.) and thus must live in habitats that can provide this, as well as adequate warmth, moisture, and prey. It is also thought that rubber boas maintain a relatively small home range as many individuals are often captured in the same vicinity year after year, although individuals may occasionally migrate due to competition, lack of prey, or other pressures.

Range: Rubber boas are the most northerly of boa species. The distribution of rubber boas covers a large portion of the western United States, stretching from the Pacific Coast east to western Utah and Montana, as far south as the San Bernardino and San Jacinto Mountains east of Los Angeles in California, and as far north as southern British Columbia. There have also been rare sightings in Colorado and Alberta in addition to the states/provinces that they are known to thrive in: California, Oregon, Washington, Nevada, Utah, Wyoming, Montana, Idaho, and extending to its northernmost range in British Columbia. This is also the highest latitude of any boa, that is to say the closest point to either pole for a boa.

Found in these States: CA | ID | MT | NV | OR | UT | WA

Diet: Rubber boas feed primarily on young mammals such as shrews, voles (such as long-tailed voles), mice (such as deer mice),s etc. When they encounter nestling mammals, they try to consume the entire litter and fend off the mother with their tail. This is why they often have extensive scarring on their tails. Rubber boas have also been known to prey on salamanders, possibly frogs, snake eggs, lizard eggs, lizards, young birds, small birds, young bats, and there have even been instances of them eating other snakes.

Reproduction: Rubber boas are viviparous (give birth to live young) and can have up to 9 young per year, although litters of 1 to 5 are much more common. Rubber boas are less prolific than many snakes found in the US and Canada with females only reproducing on average once every four years. Mating occurs shortly after reemergence from brumation in the spring, and young are born anywhere from August to November later that year.

Status: Listed as Least Concern in view of the wide range, presumed large population, large number of locations, and because it is unlikely to be declining fast enough for listing in a more threatened category.

Taxonomy: