Thamnophis elegans elegans - Mountain Gartersnake
Nonvenomous
Gartersnakes have toxins in their saliva which can be deadly to their prey and their bite might produce an unpleasant reaction in humans, but they are not considered dangerous to humans.
Size
Thamnophis elegans measures 18 - 43 inches in length (46 - 109 cm).
Appearance
A medium-sized slender snake with a head barely wider than the neck and keeled dorsal scales. Ground color is a dark olive-brown or black with no red markings. 3 well-defined light stripes on the back and sides. The dorsal stripe is yellow, orange, or white. The lateral stripes may be paler. Underside is pale with few markings, and is sometimes darker in the center.
Behavior
Active in daylight. Chiefly terrestrial - not as dependant on water as other gartersnake species, but more likely to be found near water. When frightened, this species will sometimes seek refuge in vegetation or ground cover, but it will also crawl quickly into water and swim away from trouble.
If frightened when picked up, this snake will often strike repeatedly and release cloacal contents.
Diet
This snake eats a wide range of prey (among the widest of any snake species), including amphibians and their larvae, fish, birds, mice, lizards, snakes, worms, leeches, slugs, and snails.
Reproduction
Breeds primarily in spring, with young born live July - Sepember.
Range
In California, this subspecies, Thamnophis elegans elegans - Mountain Gartersnake, is found throughout the Sierra Nevada Mountains, through most of the northern part of the state except for the outer Coast Ranges south at least as far as Mt. St. Helena. There is an isolated population in the San Bernardino mountains and in the Sacramento Valley. Ranges out of the state north into Oregon and to the edge of northern Nevada..
The species Thamnophis elegans - Western Terrestrial Gartersnake, ranges widely from the California coast north into Canada and east to NewMexico, Colorado, Wyoming, Montana, and South Dakota, with an isolated population in Baja California Norte, Mexico..
Habitat
Inhabits streamsides, springs, mountain lakes, in grassland, meadows, brush, woodland, and coniferous forest.
The species Thamnophis elegans - Western Terrestrial Gartersnake, occurs from sea level to 13,100 ft. (3,990 m) in elevation in Colorado. (Stebbins, 2003)
Taxonomic Notes
T. e. vagrans intergrades with T. e. elegans in northeast California in Modoc and eastern Siskiyou counties and in south central Oregon (this snake was formerly classified as the subspecies Thamnophis elegans biscutatus - Klamath Gartersnake. Intergrades with T. e. elegans also occur along the southern and southeastern edge of the Sierras.
Three subspecies of Thamnophis elegans are found in California - T. e. vagrans - Wandering Gartersnake, T. e. e.egans - Mountain Gartersnake, and T. e. terrestris - Coast Gartersnake.
Rossman, Ford, and Seigel (1996) emphasize that a detailed study of geographic variation throughout the range of Thamnophis elegans is badly needed.
Bronikowski and Arnold (2001, Copeia 2001:508-513) found several clades within T. elegans that do not always follow the subspecies boundaries, and concluded that there was no support for the race terrestris. Presumably, the former T. e. terrestris snakes become T. e. elegans.
Hammerson (1999, Amphibians and Reptiles of Colorado. 2nd ed. Univ. of Colorado Press) synonymized T. e. arizonae and T. e. vascotanneri but retained three subspecies, T. e. vagrans, T. e. elegans, and T. e. terrestris.
Conservation Issues (Conservation Status)
Not known to be threatened, but gartersnakes have been negatively impacted by competition with introduced bullfrogs and non-native fish in some areas. High-altitude populations of this snake may decline if populations of high-altitude frogs continue to decline.
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