Narrow-headed Garter Snake
Thamnophis rufipunctatus
A highly aquatic, fish-eating garter snake of clear mountain streams, notable for its unusually narrow head.
- Venomous?
- Mildly venomous
- Adult length
- 0.5-1.0 m (1.6-3.3 ft)
- Range
- Mountain streams of Arizona, New Mexico, and northern Mexico
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Overview
The narrow-headed garter snake is a specialized aquatic predator restricted to clear, rocky mountain streams in the southwestern United States and northern Mexico.
Its elongated, narrow head is an adaptation for catching fish underwater, and the species has declined in parts of its range due to stream degradation and non-native predators.
How to identify it
- Gray to brown background with small dark spots scattered across the back
- Dorsal stripe usually faint or absent
- Distinctively narrow, elongated head compared to other garter snakes
- Keeled scales
- Round pupils
- Distinguished from other Thamnophis species by its unusually slender head shape and spotted pattern
Habitat & range
Restricted to clear, cold, rocky mountain streams and rivers in the Mogollon Rim region of Arizona, adjacent New Mexico, and the Sierra Madre Occidental of Mexico.
Behavior, diet & reproduction
Almost entirely aquatic, feeding primarily on native fish species caught underwater. Rarely strays far from streams. Populations have declined due to water diversion, stream degradation, and predation by introduced fish and bullfrogs. Considered a species of conservation concern.
Frequently asked questions
Why is it called narrow-headed?
It has an unusually elongated, slender head compared to other garter snakes, an adaptation for catching fish.
Is this species threatened?
Yes, it has declined in parts of its range due to stream habitat degradation and invasive predators.
Where does it live?
It is restricted to clear mountain streams in Arizona, New Mexico, and northern Mexico.
What does it eat?
It feeds almost exclusively on native fish caught in flowing water.
Narrow-headed Garter Snake guides
In-depth guides for identifying and understanding Narrow-headed Garter Snake.
