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Rattlesnakes are primarily associated with the dry, semi-arid grasslands of the southern extremes of British Columbia. Denning sites tend to be at the lower elevations in the hottest valleys of the province (eg. Thompson, Okanagan, etc.), so early in the spring, this is where the animal is most usually encountered. However, recently, radio-tracked rattlesnakes have ventured higher up in the valleys than one would expect, taking them into lower-elevation forests during the hottest part of the summers.

Western rattlesnakes range from British Columbia in the north to Baja California in the south. They can be found as far east as Utah, Idaho and Arizona. The subspecies of rattlesnake which occurs in BC extends south through Oregon state and into northern California.

As mentioned, these animals are found within the hotter, drier valleys of southern BC. They range from Lytton in the west and north to Kamloops. They are found throughout the Okanagan valley from the border to Vernon, and through the Boundary region of Grand Forks and Christina Lake.

Globally, there are many species of rattlesnakes, found primarily in North and Central Americas, although some species extend into the northern half of South America.

Rattlesnakes are an amazing and important part of our native grassland fauna, and the animals should be left alone unless they are clearly posing a threat. As mentioned above, the likelihood of encountering a rattlesnake while hiking is unlikely, but when it occurs, people should simply stop walking, determine where the animal is, and then move away. Rattlesnakes will not pursue people, as is commonly thought. Keeping rattlesnakes (and all native BC fauna) as pets is not permitted. Report any situations of people keeping rattlesnakes in captivity to a local Conservation Officer.

Until recently, the scientific name of these animals was Crotalus viridis oreganus. This meant that rattlesnakes in BC and the prairies of Canada were considered the same species. Molecular research in the early 2000s showed that these two groups of snakes could be traced back to a historic ‘split’ in the rattlesnake clade of the western USA, and this resulted in the Western Rattlesnake being renamed as Crotalus oreganus oreganus. There are other subspecies or ‘races’ of Crotalus oreganus, but only C. o. oreganus is found in BC. This re-labeling of the animal essentially ‘created’ a new species of rattlesnakes in Canada, and in doing so, placed more focus on the status of rattlesnakes in BC.

The Danger of Rattlesnake Bite: Much of the fear and persecution of rattlesnakes is due to the fact they are our only venomous species. Certainly, the animal deserves respect and should never be handled. In the event of a bite, the victim should remain calm (insect bites kill more people each year in North America than snakes), and be transported to a medical facility as quickly as possible. Rattlesnake bites normally show up as two small puncture holes side-by-side (from the two front fangs of the animal). Different opinions exist as to how bites should be treated, so leave this up to a medical professional. The venom of the Western Rattlesnake is not nearly as potent as that of many other venomous snakes, including some other rattlesnake species. The severity of the bite depends on many factors, such as the age, size and health of the victim, and the location of the bite. Again, let medical professionals decide on the best course of action.

Take steps to prevent rattlesnake bites when hiking within the range of the animal, in a fashion analogous to being cautious when in bear country. Stay on trails, and always look where your hands or feet are going. Don’t wear sandals – stick with good footwear, and don’t wear shorts – even light pants have been shown to sometimes reduce the amount of venom that a rattlesnake may inject when biting a person on the leg. Young rattlesnakes do not have more or less toxic venom than adult snakes, and although they may inject relatively less venom than a larger animal, anyone bitten by even the smallest rattlesnake should immediately seek medical attention.

The important thing to remember is that these are timid animals, and with common sense and precaution, we can minimize danger to both humans and snakes.

The Rattle of the Rattlesnake: The rattle of these snakes is one of their more fascinating features. Many snakes vibrate their tail when threatened (like the gopher snake), but only the rattlesnakes have evolved a device that actually makes noise. Why and how this adaptation came about is not clear. We do know that each time an animal sheds it adds another segment to the rattle. But, because snakes do not necessarily shed once per year (it may be more, or less), and because rattles also break off from time to time, the number of segments on a rattle is only a rough guide to the age of the animal.