Common Garter Snake

Q: What are the chances of seeing a Common Garter Snake in Isle Royale National Park?

Very likely. About 70% of wildlife watchers report a Common Garter Snake sighting in Isle Royale National Park on a given day, based on 85 verified sightings from GBIF citizen-science data from 2019 to 2026. Over three days the chance rises to over 90%, if each day is a fresh chance.

Q: What time of day is best to see a Common Garter Snake?

Between 2 and 5 pm. Across all the parks we cover, that three-hour window holds the most Common Garter Snake sightings with a recorded time, and about 9 in 10 of them come between 6 am and 6 pm: it is a daytime animal.

Q: Is Isle Royale National Park the best place to see a Common Garter Snake?

3rd of 18. Of the 18 parks where we can rate Common Garter Snake sightings, Isle Royale National Park ranks 3rd at about 70%. The best odds are in Wood Buffalo National Park (Canada, about 80%) and Cape Breton Highlands National Park (Canada, about 70%). All parks ranked.

Q: Where does the Common Garter Snake sighting chance come from?

GBIF citizen-science records. It is estimated from how often the Common Garter Snake is recorded against all the reptiles logged in Isle Royale National Park (85 verified sightings from 2019 to 2026), calibrated against known sighting rates. Figures are rounded to the nearest 10% because citizen-science data supports honest approximations, not decimals, and months with records from fewer than five people show "—". How it works.

Thamnophis sirtalis

Silhouette: Alex Slavenko · PhyloPic

LCLeast ConcernNTVUENCR

KingdomAnimalia (Animals)
PhylumChordata (Chordates)
ClassSquamata
FamilyColubridae (Colubrid Snakes)
GenusThamnophis (Garter Snakes)
SpeciesThamnophis sirtalis (Common Garter Snake)

Daily sighting probability ~70% · Very likely

at Isle Royale National Park

In 3 days >90%

85 Verified sightings at Isle Royale National Park From 2019 to 2026

2,656 In all 18 parks

August Best month

☀️ Diurnal When it's spotted

About the Common Garter Snake

The common garter snake (Thamnophis sirtalis) is a species of snake in the subfamily Natricinae of the family Colubridae. The species is indigenous to North America and found widely across the continent. There are several recognized subspecies. Most common garter snakes have a pattern of yellow stripes on a black, brown or green background, and their average total length (including tail) is about 55 cm (22 in), with a maximum total length of about 137 cm (54 in). The average body mass is 150 g (5.3 oz). The common garter snake is the state reptile of Massachusetts.

The subspecific name fitchi is in honor of the American herpetologist Henry Sheldon Fitch. The subspecific name pickeringii is in honor of the American naturalist Charles E. Pickering. Current scientific classification recognizes 12 subspecies (ordered by date):

A trinomial authority in parentheses indicates that the subspecies was originally described in a genus other than Thamnophis. Common garter snakes are thin snakes. Few grow over about 4 ft (1.2 m) long, and most stay smaller. Most have longitudinal stripes in many different colors. Common... Wikipedia →

Sounds

Recording0:08

Canada · 2021

Recording0:04

Canada · 2024

Global Distribution

Where it is recorded most Known range (GARD, Roll et al. 2017 & Caetano et al. 2022)Our parks where it lives Our cities where it livesIn captivity: 17 zoos & centres

Parks Where Found

#	Park	Country	Daily sighting probability
1	Wood Buffalo National Park	🇨🇦 Canada	~80%
2	Cape Breton Highlands National Park	🇨🇦 Canada	~70%
3	Isle Royale National Park	🇺🇸 United States	~70%
4	Point Pelee National Park	🇨🇦 Canada	~50%
5	Voyageurs National Park	🇺🇸 United States	~50%
6	Acadia National Park	🇺🇸 United States	~50%
7	Shenandoah National Park	🇺🇸 United States	~40%
8	Great Smoky Mountains National Park	🇺🇸 United States	~40%
9	Redwood National Park	🇺🇸 United States	~40%
10	Pacific Rim National Park Reserve	🇨🇦 Canada	~40%
11	Olympic National Park	🇺🇸 United States	~30%
12	Big Cypress National Preserve	🇺🇸 United States	~20%
13	Everglades National Park	🇺🇸 United States	~20%
14	Great Bear Rainforest	🇨🇦 Canada	~20%
15	Congaree National Park	🇺🇸 United States	~10%
16	Merritt Island National Wildlife Refuge	🇺🇸 United States	~10%
17	Glacier National Park	🇺🇸 United States	~10%
18	Grand Teton National Park	🇺🇸 United States	~10%

Cities Where Found

#	City	Country	Daily sighting probability
1	Philadelphia	🇺🇸 United States	~30%
2	Baltimore	🇺🇸 United States	~30%
3	Detroit	🇺🇸 United States	~20%
4	Boston	🇺🇸 United States	~20%
5	Montreal	🇨🇦 Canada	~20%
6	Toronto	🇨🇦 Canada	~20%
7	Washington	🇺🇸 United States	~20%
8	Vancouver	🇨🇦 Canada	~20%
9	Minneapolis [Saint Paul]	🇺🇸 United States	~20%
10	New York City	🇺🇸 United States	~10%

Zoos & Centres Where Found

#	Zoo / Centre	Country
1	Barcelona Zoo	🇪🇸 Spain	In captivity
2	North Carolina Zoo	🇺🇸 United States	In captivity
3	Ecomuseum Zoo	🇨🇦 Canada	In captivity
4	Toledo Zoo	🇺🇸 United States	In captivity
5	Wildlife World Zoo	🇺🇸 United States	In captivity
6	Saint Louis Zoo	🇺🇸 United States	In captivity
7	Dickerson Park Zoo	🇺🇸 United States	In captivity
8	Philadelphia Zoo	🇺🇸 United States	In captivity
9	Riverbanks Zoo	🇺🇸 United States	In captivity
10	Aquarama Barcelona	🇪🇸 Spain	In captivity
11	Western North Carolina Nature Center	🇺🇸 United States	In captivity
12	Trailside Museum & Zoo	🇺🇸 United States	In captivity
13	Cambridge Butterfly Conservatory	🇨🇦 Canada	In captivity
14	North Carolina Aquarium at Pine Knoll Shores	🇺🇸 United States	In captivity
15	Scales Nature Park	🇨🇦 Canada	In captivity
16	FarmHouse Fresh Animal Sanctuary	🇺🇸 United States	In captivity
17	Seattle Marine Aquarium	🇺🇸 United States	In captivity

Show all 17 Show fewer

Closest Relatives at Isle Royale National Park

Storeria occipitomaculata

Daily sighting probability ~30% · Possible

Chrysemys picta

Daily sighting probability ~40% · Likely

Before you go

What are the chances of seeing a Common Garter Snake in Isle Royale National Park?

Very likely

About 70% of wildlife watchers report a Common Garter Snake sighting in Isle Royale National Park on a given day, based on 85 verified sightings from GBIF citizen-science data from 2019 to 2026. Over three days the chance rises to over 90%, if each day is a fresh chance.

What time of day is best to see a Common Garter Snake?

Between 2 and 5 pm

Across all the parks we cover, that three-hour window holds the most Common Garter Snake sightings with a recorded time, and about 9 in 10 of them come between 6 am and 6 pm: it is a daytime animal.

Is Isle Royale National Park the best place to see a Common Garter Snake?

3rd of 18

Of the 18 parks where we can rate Common Garter Snake sightings, Isle Royale National Park ranks 3rd at about 70%. The best odds are in Wood Buffalo National Park (Canada, about 80%) and Cape Breton Highlands National Park (Canada, about 70%). All parks ranked.

Where does the Common Garter Snake sighting chance come from?

GBIF citizen-science records

It is estimated from how often the Common Garter Snake is recorded against all the reptiles logged in Isle Royale National Park (85 verified sightings from 2019 to 2026), calibrated against known sighting rates. Figures are rounded to the nearest 10% because citizen-science data supports honest approximations, not decimals, and months with records from fewer than five people show "—". How it works.

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