British Columbia is full of snakes. There, I said it. Some of you, mostly nature-minded people, will eagerly continue reading to learn something about one of the least understood—and most threatened—animal groups worldwide. Others will stop reading here, or at least want to. But some of those folks—maybe even most—will continue anyway for much the same reason we read news about airline crashes and tsunamis: our fascination with low-probability threats overrules our fear of them. At least from the safety of the couch.
The reality, of course, is that snakes aren’t really a threat except to the worms, frogs and mice they feed on. And I’m also exaggerating their ubiquity. Given its northerly location, BC is hardly full of serpents, though at least one of our nine species can be found in abundance almost everywhere except the province’s extreme northern reaches. The rest—which also reach the northern limit of their ranges here—populate areas of the southern tier, discontinuously distributed because of the labyrinthine nature of BC’s range-and-valley geography.
The Lower Mainland (five species) and warm, southern Interior valleys (six species) harbour most of this modest diversity. But what our snake fauna lacks in variety is offset by uniqueness: three species of gartersnake; primitive species like the Northern Rubber Boa; fast, agile hunters like the Great Basin Gophersnake and Western Yellow-bellied Racer; phantoms like the Sharp-tailed Snake and Desert Nightsnake; and yes, even the undeserved bogeyman of every cowboy campfire, the Northern Pacific Rattlesnake.
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Biologically speaking, snakes are fascinating creatures that date to the Jurassic period, about 150 million years ago. Though understood to have evolved through limb-reduction in an ancient lizard lineage, it’s unknown whether this was originally an aquatic or terrestrial adaptation—meaning that the many mysteries and myths about snakes go back to their origins. Perhaps to ours as well—some anthropologists believe that the high visual acuity of our primate ancestors evolved to detect snake strikes in their arboreal habitat. Meaning we might have snakes to thank for the ability to see a frisbee approaching in our peripheral vision.
This article’s purpose isn’t to argue evolutionary theory, but to celebrate the ecological importance of these animals, which provide major control on invertebrate, amphibian, fish and rodent populations in the wild; the latter a de facto ecological service to farmers, most of whom know that the more snakes on their property, the better.
Few who spend time in the outdoors in BC, even in city greenspaces, would not have had occasion to come across a snake crossing or sunning on a trail or road. While this causes consternation in some, others are thrilled with such encounters. But both should view these opportunities as special given the decline of these animals due to habitat destruction, persecution and the inevitable roadkill that comes with increased development. Eight of our snakes are completely harmless, and while the rattlesnake packs a venomous bite, avoiding the danger is far easier than avoiding the danger of wasps or even bears.
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With that in mind, here’s look at a small spectrum of BC snakes. As I like to say, snakes are friends of nature, and any friend of nature is a friend of mine.
Ode to a Gartersnake
With over 25 species, gartersnakes are the reptile most familiar to the North American public, found in virtually every terrestrial and aquatic habitat and at all but the most restrictive latitudes. They also populate children’s books wherever a cute, chirpy snake character is required. Even if you grow up terrified of giant constrictors, skulking vipers and swaying cobras, gartersnakes may still hold a place in your heart as innocent scions of the landscapes of youth. But they also have a more important function. Because most are consummate generalists that spend a lot of time feeding on frogs, tadpoles and fish in or near water, they’re of great utility in the transfer of energy between aquatic and terrestrial ecosystems. All gartersnakes bear live young and tend to den communally for winter—sometimes in high numbers.
Of BC’s three gartersnake species, the most familiar is the Common Gartersnake, which further divides into three subspecies: the Puget Sound Gartersnake of Vancouver Island, the Gulf Islands and southern Lower Mainland sports bold, yellow (or greenish) dorsal and lateral stripes on a black background; the Valley Gartersnake adds prominent red sidebars and a red cheek patch to this combination; and a similar if more subdued look is found in the Red-sided Gartersnake near the province’s eastern border. Although frequent prey to a myriad of critters from hawks to raccoons, Valley Gartersnakes can be up to a metre in length and 20-plus years old.
Those who spend time on the islands of the coast and in the Interior will also be familiar with the Wandering Gartersnake, which has a brown-to-olive ground colour and a weak yellow strip and black dots that can combine to create a checkerboard pattern. These highly aquatic snakes often fill the niche occupied by watersnakes elsewhere, swimming at will in cold freshwater, or the Pacific, and feeding heartily on fish.
Finally, the Northwestern Gartersnake of the islands and Lower Fraser Valley is a species whose variable look is its hallmark, with all manner of ground colour and a dorsal stripe that can be red, orange, cream, blue or even non-existent. Northwestern Gartersnakes are further distinguished from the other two species by a small head and less-prominent neck and feed mostly on the slugs and earthworms common to its moist, foggy habitats.
Northern Rubber Boa
For those who fear snakes, the impressively docile, almost toy-like Rubber Boa might be the ticket out of your own personal Fear Factor. This olive- or chocolate-brown animal,, whose name derives from its playdough appearance, is people-friendly: it’s small (adults rarely exceed 70 centimetres), sleepy and slow-moving (people are often freaked out by other snakes’ jerky, frantic movements) and it never, ever bites. It’s also ancient (males sport vestiges of rear limbs in the form of spurs used for tickling females), nocturnal (hence the cat-like vertical pupils), long-lived (up to 70 years!) and engages in some fascinating behaviours.
The first of these has to do with defence against larger predators: like most snakes they release a fetid combination of feces, uric acid and anal musk. If that doesn’t do the trick, the snake might flatten into a coil and flash a bright yellow belly as a sort of warning. If all else fails they contract into a ball with their head buried and blunt, nondescript tail sticking out. As a result, it is often nicknamed the “two-headed snake.” This last posture has a further utility in the Rubber Boa’s pursuit of food. Curling through the netherworld beneath leaves and logs and rocks, it seeks out the nests of small rodents, preferentially inhaling any babies it might find; when it does happen upon a nest and starts to devour the helpless young, it keeps the mother rodent at bay by fooling her into thinking its tail is its head, which she then attacks. As a result, the tails of most older Rubber boas are heavily scarred from rodent teeth. Female Rubber Boas give birth to one to four live young every few years.
Sharp-tailed Snake
This small, secretive, nocturnal burrowing snake is a ghost that comes and goes from many of the garry oak meadow and open-canopy forest edges where it’s found; it might be encountered annually at a site for a few years in a row, then disappear altogether only to turn up again years later. Common in California and Oregon, there are scattered populations in Washington state and, until recently when a single mainland population was discovered in BC, it was found in this province only on the Gulf Islands and southern tip of Vancouver Island.
The 20- to 30-centimetre snake has a reddish hue with a dusty charcoal band along each flank and a belly uniquely adorned with black crossbands—like the stripes of an old jail outfit. Its head is quite small with no discernable neck, and it’s thought to be a slug specialist. It never bites.
Like racers and gophersnakes, the Sharp-tailed Snake is confined to warm, open habitats because only in such places do ground temperatures rise high enough to incubate its eggs. Unfortunately, humans like these same sunny habitats, which are undergoing rapid destruction by urban development, putting this unique, unassuming creature atop both provincial and federal endangered species lists.
Northern Pacific Rattlesnake
Far from being the demonic desert hazard they’re depicted as, rattlesnakes are actually pretty cool. These wide-bodied animals have dark blotches on a lighter background that can be more like bands toward the tail, where they tend to encircle the body completely. They possess a rattle, of course, a very distinct neck, a wide triangular head, and vertical pupils—a combination of characters that readily distinguishes them from other BC snakes. Sit-and-wait ambush predators, they lurk along routes used by small mammals like ground squirrels and packrats, alerted to the approach of food by heat-sensing pits located between the nostrils and eyes. Like many other BC snakes, they bear a small number of live young in late summer.
Rattlesnakes are also cool in being the most reasonable form of dangerous wildlife given the lengths they go to be left alone: their first line of defence is remaining motionless (a naturalist in the Okanagan told me that for every rattler you see there are 10 you don’t); if that doesn’t work they head for cover; if you surprise, corner or get too close they issue an audio warning; they’re reluctant to bite, and, when they do, often don’t inject venom—around a third of all rattlesnake bites are “dry” because every drop wasted on defence is a drop stolen from food procurement. Thus, the Okanagan, Canada’s fastest-growing region and home to hundreds of thousands of people, averages fewer than two bites a year. And zero deaths.
The issue, at the northern edge of the rattlesnakes’ range, however, is that preferential winter den sites are located in the rocky scree of hillsides that are separated from lower foraging habitat by development such as housing and roads, bringing snakes and humans into increasing contact.
Great Basin Gophersnake
BC’s largest snake at up to 2.5 metres long, the Great Basin Gophersnake—so named for its extensive use of abandoned rodent burrows—was a natural for this list. Another reason is that it is the species that, due to its colouration, blotchy pattern and occasional habit of vibrating its tail, is most readily confused with the Northern Pacific Rattlesnake—a situation compounded by that fact that the ranges of the two species have a 90 percent overlap in the Okanagan, Thompson, Nicola, Similkameen and Fraser River Valleys. This, unfortunately, has led to even greater persecution than the animal would normally encounter.
This large, wide-ranging, egg-laying snake with a checkerboard pattern on its belly may look intimidating but it is completely harmless and the bigger the specimen the more rodent control it can carry out. These animals tend to be solitary, denning in ground squirrel burrows.
Critter Cautions
Most folks stumble upon snakes, but some (mea culpa) actually go looking for them. If you’re the type that wants to understand these animals better, it’s a harder learning curve than, say, birding. Birds are out in the open, draw attention to themselves by vocalizing and aren’t worried about much; snakes, like other small creatures, are into camouflage and hiding. A good place to expect to see these animals, however, are ecotones—areas where one type of habitat meets another—like the edges of fields and forests, along a marshy lakeshore and human-disturbed areas like borrow pits. Such areas tend to concentrate prey.
Snakes should be photographed like other wildlife—at a distance that doesn’t cause discomfort for the animal. Obviously, this is closer with small animals like snakes than it is with large mammals, but the same rules apply. Furthermore, all snakes—including rattlesnakes—are protected under BC’s Wildlife Act: it is illegal to kill, harm or remove them from the wild.
Though many people get worked up about snakebite, it’s not much of a hazard in this part of the world. On average, 20,000 people a year die of snakebite worldwide, most in sub-Saharan Africa and Asia, yet the decade average for the US is 2.1 deaths per 7,000 to 8,000 annual bites—mostly those with pre-existing medical conditions; in Canada the stats are even better—about one death/decade versus 3.3/year from wasp stings.
A large-scale study of snakebite in North America showed two disturbing trends: first, these were overwhelmingly suffered by males ages 15 to 35, and second, the vast majority occurred on the lower arm or hands, indicating the snake was being handled. By not handling venomous snakes you reduce the risk of being bitten by 99 percent; the other one per cent can me meliorated by easily followed cautions.
When travelling in rattlesnake country, stick to clear, open trails and carry a walking stick for sweeping ahead in vegetated areas. If you encounter a rattlesnake sunning on a trail that you can’t safely go around, use a stick longer than a metre to encourage it to move off. When scrambling in rattlesnake-prone areas don’t put hands or feet anywhere you can’t see them—such as reaching up into rocky crevices or stepping over logs. If you hear a rattlesnake, stop and locate the sound. If it’s close, allow the critter to calm down then back off. Once you’re a good body-length away, you can generally go around it. If you encounter a dead rattlesnake don’t touch it—the biting reflex remains intact even after death.
Naturally, there are several great online resources when it comes to snakes. Consult these for more information, range maps, organizations and other links:
Canadian Herpetological Society (CHS): canadianherpetology.ca
Reptiles of BC official website: bcreptiles.ca/snakes.htm
Learn More
Nk’mip Cellars is North America’s first Aboriginal-owned-and-operated winery. Situated on a long bench overlooking Osoyoos Lake, in BC’s south Okanagan, the winery also boasts a Desert Cultural Centre that promotes heritage knowledge and a program to protect and restore habitat for species at risk—particularly snakes. Visitors can learn about the multiyear rattlesnake radio-tracking program and watch snakes being tagged with under-skin microchips or paint applied to rattle segments that enable wildlife managers to monitor populations and work out protection strategies. nkmipdesert.com
