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Canadian Herpetological Society Société d'Herpétologie du Canada |
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Smooth Greensnake
Opheodrys vernalis
Family: Colubridae
COSEWIC status:- Not Assessed
- No Status
- Least Concern
Description
The Smooth Greensnake is a bright emerald green colour with a creamy white or yellowish belly. The dorsal scales of this species are smooth, and it has a divided anal plate. Hatchlings are blue-grey to dark green at birth. This snake can grow to 79 cm in length but most adults are less than 50 cm.
Similar Species
No other snakes in Canada are a uniform bright green. Dead Smooth Greensnakes sometimes turn blue from loss of pigmentation and are commonly misidentified as Blue Racers. In Canada, however, Blue Racers occur only on Pelee Island.
Distribution
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In Canada, the Smooth Greensnake occurs from southeastern Saskatchewan to Nova Scotia, but it is absent from eastern Manitoba and western Ontario north of Lake Superior. In the United States, this species is most prevalent in the Great Lakes region and northeastern Atlantic states, though some scattered populations occur as far southwest as New Mexico.
Habitat
The Smooth Greensnake is found in a variety of open habitats, including prairies, meadows, fields, wetland edges, forest clearings and open woodlands. It can often be found under cover, such as logs, rocks and boards. This species is most often found in habitats with grass and other dense vegetation, in which its green coloration provides excellent camouflage, protecting this snake from predators. It hibernates underground, often communally, in small mammal burrows, rock crevices, ant mounds and other features that allow it to get below the frost line. Females lay their eggs in rotting logs or stumps, under rocks, in mammal burrows or in rotting vegetation.
Biology
Smooth Greensnakes breed in spring or early summer and the female lays an average of seven cylindrical eggs in late summer. The eggs hatch in one to three weeks, depending on the temperature. The hatchlings are 9–16 cm in length and mature in about two years. Little is known about the longevity of this species. The Smooth Greensnake is an insectivore and eats caterpillars, spiders, crickets and other insects. This species may burrow into soil and decaying woody debris in search of food and can climb shrubs, tall grasses and small trees. The lifespan of the Smooth Greensnake in the wild is unknown, but individuals of this species caught as adults have lived for over six years in captivity.
Threats
Habitat loss and degradation may threaten some populations of this species. Predators include other snakes, birds and mammals, including housecats. As with all of Canada’s snake species, road mortality is a threat, especially in southern parts of the country where road density is high.