Rubber Boa: The Pacific Northwest's Native Boa Constrictor

We have garter snakes here in the coastal Pacific Northwest, but boa constrictors?  Yep, it's true!

When I first read about the Rubber Boa on the Northwest Herps page, I was sure it was a prank.  Rubber Boa, sure, you just bought it from a bin alongside rubber spiders and rubber ants, right?  But no, it turns out that the Rubber Boa is a real thing, and surprisingly common in the West.  Its range extends west all the way to the Pacific, and north all the way to southern British Columbia.

The Rubber Boa was once thought to be rare, but researchers now believe that it is actually quite common, although rarely spotted by humans.  Rubber Boas inhabit a wide variety of territory, including meadows and conifer forests, all the way to "high alpine settings" according to Wikipedia.  Rubber Boas cannot tolerate high temperatures, and prefer temperatures that are too cool for most other cold blooded animals.   They are nocturnal, and hibernate through the winter months.  

The Rubber Boa is a very primitive snake compared to its other boa constrictor brethren.  It belongs to the Charina genus, and is considerably smaller than most other boas, ranging from 20 to 26 inches long.  Unlike many other boas, the Rubber Boa is a plain olive brown color, without any camouflage patterning.  (Since the Rubber Boa lives underground and emerges only at night, it has no need for camouflage.)  

They can produce several young at once, but most likely mate only every four years - a slow reproduction rate commensurate with their long lifespan.  One Rubber Boa kept in captivity lived to be between 50 and 70 years old.  Even in the wild, Rubber Boas have been found to live twenty or thirty years.   

Being slow and small, the Rubber Boa preys mainly on baby rodents in the nest.  It spends its time underground, lurking in its own runways or poking about for the nests of voles, mice, and shrews.  It is virtually never found on the surface, even basking below ground in shallow runways or beneath debris.

The Rubber Boa's closest relative is the Rosy Boa, which is a popular pet species.  Rubber Boas are extremely docile, and are virtually never known to bite.  They rely on excreting a musky substance when they feel threatened.  (Good thing they live underground!)  Because of their calm nature, Rubber Boas are often used to help people get over a snake phobia.

You can find Rubber Boas in almost any habitat in the Pacific Northwest, by searching under rocks and other debris once the low temperature is above 50 degrees but below 80 degrees.  65 to 75 degrees seems to be the best temperature to search for Rubber Boas.  They prefer moist habitats, preferably something near a stream, or in a soggy bottom.  Grassy fields near a stream are ideal, and RubberBoas.com has a photo series to help you locate Rubber Boas.

Should you find a Rubber Boa, take a photograph, and let it be!  Remember that it is illegal to take and keep them as pets.