Reptiles
Butler's Garter Snake
Thamnophis butleri · also called Butler's garter snakes
In a damp patch of prairie remnant near the western Great Lakes, a Butler’s garter snake hunts for earthworms within the same small stretch of ground it has occupied for its entire life, a stationary lifestyle unusual among its far more wide-ranging garter snake relatives.
Overview
Butler’s garter snake, Thamnophis butleri, is a small, earthworm-specialist snake native to damp grassland, prairie remnants, and wetland-edge habitat across a limited range around the western Great Lakes region. Its remarkably small home range, narrow diet, and naturally restricted geographic distribution make it one of the more habitat-specific and behaviourally distinctive garter snakes in North America.
A snake that never wanders far
While many garter snake species roam widely across broad ranges, Butler’s garter snake has settled into a genuinely stationary lifestyle, content to spend its entire life within a strikingly small home range.
Status
Least Concern globally, though declining in parts of its naturally limited western Great Lakes range due to habitat loss from development and agricultural conversion.
Butler's Garter Snake: common questions
Why does Butler's garter snake stay so close to home?
This species maintains a remarkably small home range compared with several other garter snake species, with individuals often remaining within a limited area for their entire lives, a pattern that may relate to its earthworm-heavy diet providing reliable food close by without the need to travel widely in search of more varied prey.
What does Butler's garter snake eat?
This species feeds primarily on earthworms, supplemented by small amphibians and other invertebrates found in damp grassland and wetland-edge habitat, a diet narrower than that of several other garter snake species which often take a wider variety of prey including fish and larger amphibians.
Where is Butler's garter snake found?
This species occupies a naturally limited range centred on the western Great Lakes region of the United States and adjacent Canada, a considerably narrower distribution than the very broad ranges many other North American garter snake species occupy.
Why has Butler's garter snake declined in parts of its range?
This species has declined in parts of its naturally limited western Great Lakes range due to habitat loss from urban development and agricultural conversion of the damp grassland and prairie remnant habitat it depends on, pressures significant enough that it is considered a species of concern in several states despite remaining globally classified as Least Concern.