The Giant Garter Snake photo by George Hansen*

[Thamnophis gigas]

Click on snake picture to watch 7 mg video of Giant Garter Snake (with Eric Hansen). Smaller version here (2.7 mg).

A large aquatic snake that can be up to four feet long. It inhabits freshwater marshes, sloughs, canals, ditches and rice fields and eats small fish, tadpoles and frogs. In the historic Central Valley, vast bulrush and cattail marshes provided habitat for Giant Garter Snake and upland areas were used for basking in the sun and hibernation areas during winter floods.

GGS exists only in the Central Valley of California. If we don't protect them, the species disappears forever.

GGS was listed by the State of California as threatened in 1971 and by the federal Fish and Wildlife Service as a threatened species in 1993.

Humans have reduced the snake’s habitat by diking, channeling and draining wetlands in the Central Valley. Habitat loss due to reclamation, grazing, bulldozers and road kill is key to the present vulnerability to extinction. Other enemies include introduced bullfrogs, largemounth bass and catfish.


*George Hansen of Sacramento, California was the most knowledgeable expert on GGS when he died September 22, 1998. His son, Eric, has made available his photographs for this web site. Eric Hansen is carrying on his Dad's work on the biology and protection of Giant Garter Snake.