Thamnophis hammondii are members of the garter snake genus (1). Their dorsal color is an olive-brown or brown-gray with a yellow venter (3). They lack the dorsal stripe common in other garter snakes and instead may have two alternating rows of small black dots (2). T. hammondii are relatively, between 61 – 102 cm in length (3). Found south of Monterey county to Baja California, they are also found on Santa Catalina island (2). T. hammondii are highly aquatic, living near permanent or semi-permanent bodies of water (1). While they are a generalist predator they are specialized aquatic feeders, preying upon tadpoles, aquatic insects, and fish (2)(3).
(1) Kucera, T. (n.d.). Two-Striped Gartersnake Thamnophis hammondii (pp. 1-2) (United States of America, California Department of Fish and Wildlife, California Interagency Wildlife Task Group). Sacramento, CA: California Department of Fish and Wildlife
(2) Rossman, Douglas A., Neil B, Ford, & Richard A. Siegel. The Garter Snakes - Evolution and Ecology. University of Oklahoma press, 1996.
(3) Stebbins, R. C. & McGinnis, S. M. (2012). Field Guide to Amphibians and Reptiles of California (Revised ed.). Berkeley, CA: University of California Press.
(Photograph) © Alice Abela