Thamnophis sirtalis fitchi - Valley 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

Adults of this species measure 18 - 55 inches in length (46 - 140 cm), but the average size is under 36 inches (91 cm).

Appearance

A medium-sized snake with a head barely wider than the neck and keeled dorsal scales.

The ground color is dark gray, black or brown. The dorsal stripe is wide and yellowish, and there is a yellowish stripe along the bottom of each side. The red on the sides of this Common Gartersnake are usually confined to the area just above the lateral stripes, in a single row, alternating with dark markings.The top of the head is dark - black, dark gray, or brownish. There is sometimes a bit of red on the sides of the head. The underside is bluish gray, and it may become darker toward the tail, or may become paler.

The eyes are relatively larged compared with other gartersnake species.

Behavior

Primarily active during daylight. A good swimmer. Often escapes into water when threatened. When first handled, typical of gartersnakes, this snake often releases cloacal contents and musk, and strikes. The species T. sirtalis is capable of activity at lower temperatures than other species of North American snake.

Diet

Eats a wide variety of prey, including amphibians and their larvae, fish, birds, and their eggs, small mammals, reptiles, earthworms, slugs, and leeches. This snake is able to eat adult Pacific newts (Taricha) which are deadly poisonous to most predators.

Reproduction

Mating occurs in the spring (and possibly the fall ) and young are born live, spring to fall.

Range

This subspecies, Thamnophis sirtalis fitchi - Valley Gartersnake, is found throughout northern California, including the coast in Humboldt and Del Norte Counties, south, mostly east of the coast ranges until just south of the Monterey Bay when it extends to the coast until roughly Santa Barbara County, and west of the high Sierras to the southern San Joaquin Valley, and east of the Sierras into the Owens Valley. T. s. fitchi ranges north all the way to extreme southern Alaska, and east into western Nevada, Idaho, western Montana, western Wyoming, and northcentral Utah.

The species Thamnophis sirtalis - Common Gartersnake, has the largest distribution of any gartersnake, ranging from the east coast to the west coast and north into Canada, farther north than any other species of snake in North America.

We are following Rossman et al. for the range of T. s. fitchi along the central coast. (The juvenile snake from the central coast shown above shows T. s. fitchi characteristics.) Stebbins and others show the range of T. s. fitchi remaining east of the coast ranges south of the Bay Area. Here is an alternate map showing this distribution.

Habitat

Utilizes a wide variety of habitats - forests, mixed woodlands, grassland, chaparral, farmlands, often near ponds, marshes, or streams.

Stebbins (2003) lists the elevation record for the species (not specifically this subspecies) as 8,000 ft. (2,438 m). Conservation Issues (Conservation Status) None.