infernalis) are two distinct subspecies of the common garter snake (Thamnophis sirtalis).Both of these subspecies are found on the San Francisco Peninsula. The California red-sided garter snake or red-sided garter is a subspecies of common garter snakes found in North America. They are an endangered subspecies of garter snake. The San Francisco garter snake, considered “the most beautiful snake in North America,” is an absolute treasure residing within our very own San Mateo County. One can easily imagine that quite a few animals have been smuggled illegally into Europe over the last decade captive stock that was apparently sorely inbred for blue and red individuales. Flashing a bright teal underside, red and black stripes, and a notable red head, the snake is famous for its beautiful coloration. Garter snakes are the snakes usually found in the pockets of schoolchildren as well as in the schoolroom terrarium. Keeping a garter snake as a pet is not recommended because of its speed and specific diet. These are the native and well-established alien herps that inhabit the Bay Area, which for our purposes includes the land surrounding most of the San Francisco Bay including parts of Alameda, Contra Costa, San Francisco, San Mateo, Santa Clara, Santa Cruz, Solano, Napa and Marin counties. The San Francisco garter snake has been dubbed “the most beautiful serpent in North America,” and it's arguably one of the most endangered species, too. Despite having enlarged teeth, the garter snakes lack an efficient means of delivering venom since their gums are comparatively … have a wide diversity of colors and patterns. That is a lovely San Francisco Garter, aka Red-Sided Garter Thamnophis sirtalis infernalis. San Mateo California.Wild populations of San Francisco Garter Snake Thamnophis sirtalis tetrataenia SFG. 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. San Mateo Park Stewardship intern. The San Francisco garter snake is considered by many the most beautiful snake in … SAN FRANCISCO GARTER SNAKE Thamnophis sirtalis tetrataenia . tetrataenia) and red-sided garter snake (T.s. They need a humidity of at least 60 percent to thrive, so provide a large water bowl that will be used for bathing and often feeding as … The San Francisco garter snake (T.s. FOOD. They may hunt after dark on warm evenings. Not Dangerous (Non-poisonous) - This snake does not have venom that is dangerous to most humans. (These are listed as … Summary 5 The San Francisco garter snake (Thamnophis sirtalis tetrataenia) is a slender multi-colored subspecies of the common garter snake.Designated as an endangered subspecies since the year 1967, it is endemic to San Mateo County and the extreme northern part of … The color is a little oversaturated, but not much. These colorful, medium-sized snakes are considered harmless since their mild neurotoxic venom is not deadly to humans. SF garter snakes are active during the day. All known populations of this fantastically colored snake occur in scarce coastal and bayside wetlands in San Mateo County. In California, only rattlesnakes have venom that is dangerous to humans. Garter snakes are not dangerous. Similar to other garter snakes, San Francisco garter snakes can be housed in 20-gallon terraria with a substrate of shredded aspen, loamy soil or coconut fibers. Adults mainly eat small frogs such as the CA red-legged frog (143 KB PDF).