California Garter Snakes

Garter snakes are some our most common snakes, but in some parts of the state they can be a bit tricky to tell apart, particularly in the SF Bay Area. This guide should introduce you to the cast of characters and give you some tips on telling them apart.

Taxonomy
11 Garter Snakes Genus Thamnophis

Aquatic Garter Snake ¹
Thamnophis atratus

Western Aquatic Garter Snake ²
Thamnophis couchii

Western Terrestrial Garter Snake ³
Thamnophis elegans

Mountain Garter Snake ⁴
Thamnophis elegans elegans

Giant Garter Snake ⁵
Thamnophis gigas

Two-striped Gartersnake ⁶
Thamnophis hammondii

Checkered Garter Snake ⁷
Thamnophis marcianus

Northwestern Garter Snake ⁸
Thamnophis ordinoides

Valley Garter Snake ⁹
Thamnophis sirtalis ssp. fitchi

California Red-sided Garter Snake ¹⁰
Thamnophis sirtalis ssp. infernalis

San Francisco Garter Snake ¹⁰
Thamnophis sirtalis tetrataenia

Edited by Ken-ichi Ueda, some rights reserved (CC BY-SA)

Photo Credits

1. (c) James Gaither, some rights reserved (CC BY-NC-ND)
2. (c) randomtruth, some rights reserved (CC BY-NC-SA)
3. (c) Todd Pierson, some rights reserved (CC BY-NC-SA)
4. (c) 1999 California Academy of Sciences, some rights reserved (CC BY-NC-SA)
5. (c) Yolodave, some rights reserved (CC BY-SA)
6. (c) Bill Bouton, some rights reserved (CC BY-NC)
7. (c) Jerry Oldenettel, some rights reserved (CC BY-NC-SA)
8. (c) benet2006, some rights reserved (CC BY)
9. (c) C.V. Vick, some rights reserved (CC BY-NC-ND)
10. (c) Natalie McNear, some rights reserved (CC BY-NC)

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