In Our Backyard: Great Basin Gophersnake
In spring, the largest snake found in BC stirs from its hibernation to mate and forage. The Great Basin gophersnake (Pituophis catenifer deserticola) is found in dry, grassland or forested areas with rocky cliffs or talus slopes suitable for den sites. As they prey on small mammals, gophersnakes play a valuable role in helping protect crops from pests.
They have black or reddish-brown rectangular blotches down the back, contrasted on a creamy-yellow or grayish-yellow background. Individuals usually have a dark mask running from the corners of the mouth and around each eye. The head is small and only marginally wider than the neck with large eyes and round pupils. When threatened, gophersnakes will flatten their head, hiss loudly, and vibrate their tail, creating a convincing rattlesnake imitation. Rattlesnakes however, almost never hiss, and will produce an audible and distinct buzzing sound from their rattle that cannot be imitated by a gophersnake.
Gophersnakes are active hunters mainly seeking out rodent burrows where they will prey on the inhabitants and safely remain to digest their meal. They can also catch prey in trees or shrubs and like to eat mice, voles, and squirrels, and sometimes feast on lizards, birds and their eggs. While they can swallow smaller prey alive, Great Basin gophersnake are true constrictors, squeezing their prey until they die of asphyxiation.
Gophersnakes have large home ranges making their migration between summer foraging grounds, nesting sites and overwintering hibernacula sometimes fatal due to road crossings. Pesticide use to control rodent populations can reduce the availability of their prey. As gophersnakes superficially resemble rattlesnakes, they are sometimes unnecessarily killed by fearful humans.
In BC, gophersnakes are at the northern limit of their range. Harsh winters and their low reproductive capacity reduce their ability to recover from population declines. As a result, the Great Basin gophersnake has been federally listed as threatened. With most of its Canadian population living in the Thompson and Okanagan, it’s important to conserve its habitat in this region to prevent extirpation.