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Quick answer
The common garter snake (Thamnophis sirtalis) is North America's most familiar harmless snake, striped and often found in gardens, wetlands, and woodland edges from Canada across most of the United States. Adults average about 0.7 m, eat amphibians, fish, and worms, and are listed Least Concern — including famous Manitoba mating balls.
Top questions about the Common Garter Snake
Common Garter Snake facts at a glance
- Weight 150 g
- Length 70 cm
- Top speed 5 km/h
- Lifespan 8 years
| Scientific name | Thamnophis sirtalis |
|---|---|
| Diet | Carnivore (amphibians, fish, worms) |
| Habitat | Gardens, wetlands, meadows, and woodland edges |
| Lifespan | Around 8 years in the wild (varies by population and captivity). |
| Weight | About 0.15 kg typical adult mass (sex and region vary). |
| Top speed | Up to roughly 5 km/h when moving at speed. |
| Conservation status | Least Concern (IUCN) |
| Kingdom | Animalia |
|---|---|
| Phylum | Chordata |
| Class | Reptilia |
| Order | Squamata |
| Family | Colubridae |
| Genus | Thamnophis |
Where it lives
The common garter snake (Thamnophis sirtalis) is native to Most of the United States and southern Canada, excluding deserts of the Southwest. — recorded across North America in this guide’s range summary.
For occurrence records, see GBIF species search and sources below.
How big is a common garter snake?
An adult common garter snake measures 70 cm long — about 40% of the height of an average adult person (1.73 m) — and weighs around 150 g, a small fraction of an average adult’s body weight (70 kg).
Length vs an average adult’s height (to scale)
What is a group of common garter snakes called?
Group name (collective noun)
A group of Common Garter Snakes is called a bed.
Baby name
A baby Common Garter Snake is called a neonate.
Explore more animal collective nouns and baby animal names .
Stripes and musk defence
Usually three light stripes on a darker body; pattern varies widely by subspecies. When seized they may musk foul-smelling cloacal fluid and rarely bite mildly — they are non-venomous to humans in any medically serious sense (some have mild saliva toxins irrelevant to people).
Amphibians, fish, and earthworms
Diet includes frogs, salamanders, fish, leeches, and earthworms. Coastal populations famously eat toxic newts, sequestering toxins. Across its range it is tied to gardens, wetlands, meadows, and woodland edges, and field accounts emphasise this species’ distinctive ecology rather than generic habitat labels.
Nearly continent-wide near water
Most of the United States and southern Canada except extreme Southwest deserts — gardens, wetlands, meadows, and woodland edges. Across its range it is tied to gardens, wetlands, meadows, and woodland edges, and field accounts emphasise this species’ distinctive ecology rather than generic habitat labels.
Climate and wetland ally
Least Concern and adaptable. Narcisse Wildlife Management Area in Manitoba hosts enormous spring mating aggregations that draw tourists and need habitat protection.
Explore the Common Garter Snake
Related Reptiles
Range & geography
Conservation status of the Common Garter Snake
The common garter snake (Thamnophis sirtalis) is listed as Least Concern on the IUCN Red List. Least Concern (LC) is the IUCN's lowest-risk category, assigned to widespread, abundant species that have been evaluated and found not to be threatened. It does not mean a species faces no pressures — only that it is not currently at risk of extinction.
The common garter snake (Thamnophis sirtalis) is assessed on the IUCN Red List. Look up on the IUCN Red List .
Frequently asked questions about the Common Garter Snake
Are garter snakes poisonous?
They are not dangerous to healthy humans; bites may nick skin but lack medically significant venom for people.
What is a garter snake mating ball?
In spring, dozens of males may swarm a single female emerging from hibernation — spectacular in places like Manitoba.
Do garter snakes make good pest control?
They eat slugs, worms, and amphibians; they help in gardens without threatening people.
Can garter snakes swim?
Yes — they swim well and often hunt in ponds and ditches.
Where do common garter snakes live?
Across most of the United States and southern Canada in moist habitats.
What is a group of common garter snakes called?
A group of Common Garter Snakes is called a bed.
What is a baby common garter snake called?
A baby Common Garter Snake is called a neonate.
Sources & references
This guide is compiled and reviewed against established zoological and conservation references. Key sources for the Common Garter Snake:
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IUCN Red List of Threatened Species
Conservation status (Least Concern) reflects the IUCN Red List category for Thamnophis sirtalis.
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iNaturalist — observations & photos
Search citizen-science observations and community IDs for Thamnophis sirtalis. Useful for range checks and recent sightings — not a substitute for formal Red List status.
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GBIF — occurrence data
Global Biodiversity Information Facility species search for Thamnophis sirtalis. Explore published occurrence records used in range research.
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How we research, source, review, and update every guide for accuracy.
