| Species | Charina bottae (Blaineville, 1835) |
| Family | Boidae (Boas) |
| Status | none |
| State Rank | S4 |
| Global Rank | G5 |
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This is a thick-bodied snake with small eyes, tiny scales and a blunt tail that is similar in appearance to the head. In the Northwest, they rarely exceed 60 cm total length. The dorsal surface is uniformly tan, brown, olive, gray, charcoal or rosy pink. The underside is yellow or cream and may have dark mottling. Scales are smooth with 39 to 53 rows of dorsal scales at mid-body. The ventral scales are reduced in size as compared to most snakes. Pupils are vertical. Vestigial legs are present as external spurs located on both sides of the vent in males and occasionally in females. Females are larger (up to 830 mm) than males and the spurs, when present, are much smaller. Scars are common along the body and tail. Juveniles resemble adults but are pinkish in coloration. See Photos Page.
The Rubber Boa is sometimes confused with the Racer (Coluber constrictor) because both species have similar coloration. Racers differ in having large eyes, large dorsal scales and a tail that tapers to the tip. Racers are fast, aggressive snakes that will strike and bite if cornered or handled whereas Rubber Boas are slow, non-aggressive snakes that are easily captured and handled. See Key Features Page.
Surface activity at overwintering locations starts in March. Activity continues through October. Rubber Boas have not been studied in Washington. Breeding in other areas of the Northwest takes place in April and May. Rubber Boas give birth in the fall to 2 to 8 young.
Rubber Boas are found in all Washington ecoregions. Few records have been submitted for the coastal forests, higher elevations of the Cascade Mountains or the central Columbia Basin. See Distribution Map.
For information on the complete range of this species, see NatureServe Explorer.
Rubber Boas are found in a variety of habitats including prairies, shrub-steppe, grasslands and forests of various types. Their distribution is patchy in Washington. They are common in some areas and apparently absent from others. The wet, dense forests of the Pacific Coast Ecoregion and the dry, shrub-steppe habitats of the central Columbia Basin are not considered typical Rubber Boa habitat, but Rubber Boas have been found in both.
Rubber Boas are active at night and spend much of their time below ground. They are usually found by turning woody debris and rocks or by searching roads at night. It is often possible to return to the same site year after year and find them or their shed skins.
The current rank is based on the assumption that Rubber Boas are more common than current records indicate because 1) it is difficult to find nocturnal, semi-fossorial snakes, 2) the records are primarily from opportunistic encounters and not systematic surveys, and 3) they occupy a variety of habitat types suggesting they are able to adapt to a variety of habitat conditions.
Observations from areas not indicated on the map can be submitted to the WDFW herp database by contacting Lori Salzer by E-mail salzeljs@dfw.wa.gov. Of particular interest are observations from the Columbia Basin and Pacific coastal areas and observations that occur outside the known distribution. Basic life history and habitat information pertaining to Washington occurrences is also needed.
None.
At this time, little is known about factors that may threaten populations. Down woody debris, fractured rock, and loosely compacted rock are generally considered important for maintaining this species. Protection of overwintering sites may be important for sustaining local populations.
Nussbaum et al. (1983)
Hallock, L.A. and McAllister, K.R. 2005. Rubber Boa. Washington Herp Atlas. http://www1.dnr.wa.gov/nhp/refdesk/herp/
Last updated: December 2005