Northwestern Garter Snake (Thamnophis ordinoides)

Created on Tuesday, 22 February 2011 09:57
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Thamnophis ordinoides is a small snake, usually only having a body length of 14 to 36 inches when fully grown. The Northwestern Garter Snake ranges more in body coloring that any other garter snakes. Its color can vary from almost black to olive with most snakes having a dark stripe down their backs. Most Northwestern snakes will also have a bright stripe down their sides that also range in color from white to yellow. You can positively identify them from other garter snakes by looking for a pale upper lip.

Northwestern Garter Snake
Northwestern Garter Snake from Vancouver Island


Northwestern’s, like most snakes, will just about eat anything it’s capable of overpowering. But, they usually prefer to feed on slow moving insects like worms, slugs and snails. Larger adult have also been known to eat smaller amphibians, fish, small rodents and even small eggs. Also, like other snakes, food is swallowed whole.


Northwestern Garter Snakes, along with other garter snakes had been believed not to produce any venom. Now, researchers have found that these snakes do produce a mild neurotoxin. The venom is not strong enough to affect humans and garter snakes have no way to deliver the venom into human tissue. Garter snakes have small teeth, not fangs. The venom is delivered into their prey by a chewing action that breaks the prey’s skin.

Where to find Northwestern Garter Snakes

Northwestern Garter Snakes can be found (as the name implies) in north west regions of the USA and the south western regions of Canada.  They are abundant in coastal areas from Oregon to the middle of British Columbia.

Garter Snakes will den over winter, so they can only be seen from spring to fall. They are usually found in areas with lots of vegetation including forests, fields and meadows and even in urban areas like large parks or over-grown lots.

Observing Northwestern Garter Snakes

On sunny days, you will often find these snakes sunning themselves on gravel roads, paths, large low rocks and on hiking trails. They make great candidates for viewing and photography as most will simply freeze in place as you approach. If you wait long enough, most will eventually start investigating you by turning their heads towards you and using their toque to take a smell. Getting too near will almost always cause them to flee at an amazing rate into the nearest vegetation. Once under cover they are almost impossible to see or find. For taking photos, you should have at least a 200 mm telephoto lens on you DSRL camera or a strong zoom if you’re using a point and shoot camera. This will let you take photographs at a distance that won’t spook the snake you are viewing.


Should you decide to handle these reptiles, be forewarned that most will release a foul smelling liquid from the base of their tails when held. Although not an aggressive snake, some will also try to bite. Although not capable of causing any real harm, large adults can deliver a nasty pinch if they manage to catch you in a sensitive area. Remember to wash your hands after handling them, as with other reptiles, snakes may carry Salmonella bacteria.

Thamnophis ordinoides
Thamnophis ordinoides