Reptile · GBIF taxon 6161469
Thamnophis sirtalis tetrataenia
Thamnophis sirtalis tetrataeniaAlso known as SF Garter Snake
Draped in brilliant turquoise, coral-red, and black stripes, the San Francisco garter snake ranks among North America's most striking reptiles. Active during warm daylight hours, these secretive hunters slip between dense marsh vegetation and open sunning spots near quiet freshwater ponds. As endemic residents of a narrow coastal corridor, their survival relies directly on healthy wetland ecosystems and abundant native amphibian prey.
Semi-AquaticColorful
Licensed reference(c) j k, some rights reserved (CC BY) · cc-by
—observations
—countries
—peak records
EndangeredConservation statusIUCN Red List categoriesLCNTVUENCREWEXEndangeredRed List categories, explained →
Diet & prey
- California Red-legged Frogs
- Pacific Treefrogs
- Tadpoles
Predators
- Red-tailed Hawks
- Great Blue Herons
- Domestic Cats
ThreatsHabitat loss, wetland degradation, prey decline, illegal collection
HabitatsWetlands, freshwater ponds, coastal marshes, grasslands
Life span6–10 years in the wild
Size / weightNot available
Classification
- FamilyColubridae
- SpeciesThamnophis sirtalis tetrataenia
Range data is not available yet.
Interaction riskLow
- Low
- Moderate
- High
- Very high
- Why interaction risk is low
- Non-venomous and harmless to humans, though capable of a mild defensive bite if wild individuals are handled.
- What to notice
- Distinguished by striking turquoise-blue undersides, coral-red heads, and bold red and black dorsal stripes.
- Support conservation
- Observe strictly from marked trails without disturbing vegetation or handling individuals, as touching or capturing them is illegal.
Responsible observation
- Spotting behavior: Look for sudden bright turquoise flashes along pond edges on sunny spring mornings.
- Trail etiquette: Remain on designated paths in protected preserves to prevent trampling delicate marsh bank burrows.
- Distance rule: Give basking snakes ample room so they can retreat naturally without feeling threatened.
Primary Prey (c) Greg Schechter, some rights reserved (CC BY) · cc-by
Prey The High Fin Sperm Whale / CC BY-SA 3.0 · cc-by-sa
Competitor (c) Steve Jurvetson, some rights reserved (CC BY) · cc-by
Predator Buteo_jamaicensis_1.jpg: Alan Vernon derivative work: Berichard (talk) / CC BY 2.0 · cc-by
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