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Canadian Herpetological Society Société d'Herpétologie du Canada |
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Great Basin Gophersnake
Pituophis catenifer deserticola
Family: Colubridae
The Great Basin Gophersnake is a subspecies of the Gophersnake (Pituophis catenifer).
COSEWIC status:- Threatened
- Threatened
- Least Concern
Description
The Great Basin Gophersnake is a large, heavy-bodied snake which may reach 2 m in total length. It is cream or yellowish with dark black, brown or reddish rectangular blotches down the back alternating with blotches on the sides to form a checkered pattern. On some individuals, the blotches on the back may be fused to those on the sides. A dark line runs across the head in front of the eyes and two lines extend from each eye to the mouth: one straight down from the eye and the other toward the back of the mouth. The belly is cream coloured with brown markings, often forming a checkered pattern. The scales are keeled.
Similar Species
Gophersnakes are often confused with the Western Rattlesnake and small individuals may be confused with the Desert Nightsnake. However, the rattlesnake has a distinctly triangular head, vertical pupils and usually a rattle at the tip of the tail. The Desert Nightsnake has vertical pupils, a large blotche on either side of the neck and another behind the head.
Distribution
Click for larger image
In Canada, the Great Basin Gophersnake is found in the Thompson, Okanagan, Similkameen, Kettle Creek, Fraser and Nicola valleys in southern British Columbia. South of the border this species occurs throughout the western U.S. as far south as Arizona and New Mexico. The seven sub-species of Gophersnake are widely distributed throughout North American and occur in British Columbia, Alberta, Saskatchewan and the western and central U.S. east to Indiana and south northern Mexico.
Habitat
This species inhabits open habitats such as grasslands and fields, woodlands, open pine forests, scrubland, and rocky habitats. Gophersnakes hibernate, often communally with other snake species, in talus slopes and crevices in rocky habitat. This species lays its eggs on south facing slopes in mammal burrows or burrows excavated in loose sand and under rocks or logs. Rocks, deadfall, shrubs and other cover are important microhabitats that are used for shelter and thermoregulation.
Biology
Gophersnakes mate in the spring and females lay two to eight eggs in late June or early July. The young hatch in late August or September and are 20–50 cm in length. Males of this species reach maturity in one to two years and females in three to five years, and mature females may only reproduce once every two years. Individuals can live for more than 30 years. Gophersnakes primarily eat small mammals, especially rodents, and in doing so they provide excellent pest control around farms and human settlements. They also eat birds, birds' eggs, lizards and invertebrates. They are primarily active during the day but during very hot weather they may seek out underground retreat sites and become more active at night. Gophersnakes often travel large distances (> 1 km) between their hibernation site and summer habitat. When threatened, Gophersnakes may hiss loudly, vibrate their tail and rear up.
Threats
Significant habitat loss, largely as a result of agricultural development, has occurred throughout this species’ Canadian range. The expansion of the road network and associated road mortality is also a significant threat to this species, especially in the most developed parts of its range. Like many snakes, Gophersnakes are often killed by misinformed people who either think they are dangerous or simply don't like snakes.