common garter snake

(Thamnophis sirtalis)

Conservation Status
common garter snake
Photo by Luciearl
  IUCN Red List

LC - Least Concern

 
  NatureServe

N5 - Secure

S5 - Secure

 
  Minnesota

not listed

 
           
           
           
 
Description
 
 

Common garter snake is a medium-sized, typical snake. It is the most common snake in Minnesota.

Adults can be from 14 to 48 long at maturity, though they are usually no more than 16 in length. Females are slightly longer and significantly heavier than males.

The background color is variable and may be light brown to black or olive green. There are three pale stripes that run the length of the body. The central stripe is light yellow. The lateral stripes are cream-colored to pale yellowish, and are on the second and third scale rows counting up from the belly (ventral) scales. There are two rows of alternating black spots on each side between the central and lateral stripes. The spots may be prominent and invade the stripes, or may be obscured on dark colored individuals. The upper (dorsal) and lateral scales have a narrow raised ridge (keel) along the centerline. At mid-body there are 19 to 21 rows of scales. On the eastern garter snake red skin may be visible between the scales when it stretched over recently consumed prey, but there are no red scales. On the red-sided garter snake there are bold red bars or spots between the central and lateral stripes.

The belly is white and may be tinted yellowish or bluish. There is usually a row of small black spots at the ends of the ventral scales. These spots are partially hidden by overlapping ventral scales. The anal plate is not divided. Underneath the tail there are two rows of scales (subcaudal scales).

The head and neck are uniformly dark usually with a pair of yellow spots. The scales above the mouth (labial scales) are the same color as the lateral stripe. Usually only one or two labial scales have a bold black border.

The subspecies red-sided garter snake (Thamnophis sirtalis parietalis) has bold red bars or spots on the side between the dorsal and lateral scales.

 
     
 

Size

 
 

14 to 48

 
     
 

Similar Species

 
 

Plains garter snake (Thamnophis radix) lateral pale stripes are on the third and fourth scale rows counting up from the ventral scales. Usually all labial scales have a bold black border.

Lined snake (Tropidoclonion lineatum) is much shorter, only 8 to 12 long at maturity. The 3 stripes are off-white. There are 2 rows of dark, half-moon marks on the belly. In Minnesota it has been found only in Blue Mounds State Park.

 
     
 
Habitat
 
 

Wide variety of habitats. Moist, grassy places. Forests, forest edges, prairies, meadows, and other areas near water.

 
     
 
Ecology
 
 

Behavior

 
 

 

 
     
 

Lifespan

 
 

5 to 10 years

 
     
 

Life Cycle

 
 

Overwintering common garter snakes emerge from their overwintering sites in March. Females reach sexual maturity in 2 or 3 years. Breeding takes place in April or May. Gestation takes 83 to 102 days. In July to September the female gives birth to a litter of 4¾ to 9½ long, live young. The litter size is usually 10 to 20 but may be as few as 5 or as many as 60. The young are on their own from the day of their birth.

In late October they gather in large numbers, sometimes with other species of snakes, in rodent burrows, abandoned ant mounds, or under sidewalks, to overwinter. As the temperature drops they enter a state of sluggishness, inactivity, and torpor (brumation). It is similar to hibernation in mammals, but they stir occasionally to drink water.

 
     
 

Food

 
 

Earthworms, amphibians, leeches, slugs, snails, insects, crayfish, small fish, bird eggs, mice, other snakes, and carrion.

 
     
 

Toxicity

 
 

Common garter snakes are venomous but their venom is not strong enough to cause serious harm to humans. Allergic reactions to a bite from a common garter snake are rare. Reaction to a bite is normally little more than swelling and irritation around the puncture wound. However, like a bite from any animal, bacteria from the mouth of the snake can cause an infection.

 
     
 
Distribution
 
 

Distribution Map

 

Sources

4, 7, 14, 24, 29, 30, 74, 76, 78.

 
  9/7/2022      
         
 

Occurrence

 
 

Common

 
         
 
Taxonomy
 
  Class Reptilia (reptiles)  
  Superorder Lepidosauria  
  Order Squamata (snakes and lizards)  
  Suborder Serpentes (snakes)  
  Infraorder Alethinophidia  
  Superfamily Colubroidea  
 

Family

Colubridae (colubrid snakes)  
 

Subfamily

Natricinae  
 

Genus

Thamnophis (garter snakes)  
       
 

Subordinate Taxa

 
 

bluestripe garter snake (Thamnophis sirtalis similis)

California Red-sided garter snake (Thamnophis sirtalis infernalis)

Chicago garter snake (Thamnophis sirtalis semifasciatus)

common garter snake (Thamnophis sirtalis lowei)

eastern garter snake (Thamnophis sirtalis sirtalis)

maritime garter snake (Thamnophis sirtalis pallidulus)

New Mexico garter snake (Thamnophis sirtalis dorsalis)

Puget Sound garter snake (Thamnophis sirtalis pickeringii)

red-sided garter snake (Thamnophis sirtalis parietalis)

red-spotted garter snake (Thamnophis sirtalis concinnus)

San Francisco garter snake (Thamnophis sirtalis tetrataenia)

Texas garter snake (Thamnophis sirtalis annectens)

valley garter snake (Thamnophis sirtalis fitchi)

 
       
 

Synonyms

 
 

Coluber sirtalis

 
       
 

Common Names

 
 

common garter snake

 

 

 

 

 

 

 

 

Glossary

Anal plate

In snakes: the large scale in front of and covering the anus. In turtles: one of the posterior plates of the lower shell (plastron). In Lepidoptera: the often hardened shield on the dorsal surface of the last (10th) segment of the abdomen.

 

Brumation

Winter dormancy in reptiles. A cold-induced period of sluggishness, inactivity, and torpor in reptiles, akin to hibernation in mammals, but they stir occasionally to drink water.

 

Ventral scales

On snakes, the row of enlarged, elongated scales extending on the belly from the neck to the anal plate.

 

 
 
Visitor Photos
 
           
 

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Lane Keller

 
 

This snake was hiding in the rocks next to the river where it was basking in the sun to start of the day off with hunting leopard frogs that were everywhere in the state park.

  common garter snake  
           
    common garter snake      
 

Alfredo Colon

 
    common garter snake   common garter snake  
 

Theodore Loftsgard

 
 

Red sided garter snake

near my house in a trench under sod pieces. Relocated to Quarry Hill.

  common garter snake  
 

Margot Avey

 
 

This guy was big!

 
    common garter snake   common garter snake  
 

Kirk Nelson

 
 

Red-sided Garter Snake

 
    common garter snake      
 

Luciearl

 
  This garter sat very still so "I couldn't see it". Actually saw it very well and was able to take several photos. About 2 ft. long.   common garter snake  
           
        common garter snake  
 

Jimmy Hultgren

 
    common garter snake      
 

Chris H.

 
  After a record cold week, the sunshine finally warmed things up enough for some springtime sightings like pasque flowers and this little garter.   common garter snake  
 

Robert Briggs

 
  I'm fairly certain this is a common rather than plains. Didn't get close enough with this picture - I had a wide angle lens on at the time.   common garter snake  
 

Ida Marie

 
  I was in the bee balm photographing that red spotted purple butterfly yesterday and 4 and 1/2 feet off the ground this snake appears and scared the living day lights out of me....he had to be at least 3 feet long.   common garter snake  
           
 
MinnesotaSeasons.com Photos
 
 

eastern garter snake (Thamnophis sirtalis sirtalis)

 
    common garter snake   common garter snake  
           
    common garter snake   common garter snake  
           
    common garter snake   common garter snake  
           
 

red-sided garter snake (Thamnophis sirtalis parietalis)

 
    common garter snake      

 

Camera

     
 
Slideshows
 
Common Garter Snake (Thamnophis sirtalis)
Andree Reno Sanborn
  Common Garter Snake (Thamnophis sirtalis)  
 
About

NH Conservation Status: Not listed

State Rank Status: Widespread and secure

Distribution: Throughout NH

Description: A small striped snake measuring 18-26 inches. Has variable color patterns but typically has 2-3 yellow, brownish, or greenish stripes running vertically down the top and sides of the snake. May also have variable black spots between the stripes.

Commonly Confused Species: Eastern ribbon snake; Brown snake

Habitat: Found in a variety of habitats including woodlands, hillsides, wetlands, backyards, and even urban areas. Will use a variety of cover objects for shelter including rocks, logs, stumps and other debris such as trash piles and sheet metal.

Life History: Breeding may occur in spring or fall. Ten to 40 live young are born from July to September. Hibernation may be solitary or communal in rock crevices, holes, stumps, or foundations.

Conservation Threats: Species is secur

from: http://www.wildlife.state.nh.us/Wildlife/Nongame/snakes/profile_garter_snake.htm

 
Thamnophis sirtalis (Eastern Garter Snake)
Allen Chartier
  Thamnophis sirtalis (Eastern Garter Snake)  

 

slideshow

       
 
Visitor Videos
 
       
 

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Other Videos
 
  Wild Thamnophis sirtalis sirtalis eating Bufo americanus!! 1 June 2013
FlapsMemoir
 
   
 
About

Published on Sep 20, 2013

This is actually six (6) varying, but related—save an adorable, happy ending—videos pasted together, but the feeding segment starts at the 2:04 mark and is most of the video. I strongly encourage You to read my notes below, too; some are just short clarifications of my lazy articulation or when I can't be heard well, while others—such as the 3:37 and 5:34 notes—detail elaborations, knowledge and trivia. I am nervous when on camera, even just speaking and not seen, especially when something as exciting or a first-time event like this is going on, so I cannot think clearly and leave a lot out and am not able to utilize my technical terminology well. Thanks, and enjoy!!

1:26 -- '...a good reference to my knee, my hand...' and fat *near* the tail; not 'fat tail', haha. Having watched this video a few times now, this specimen may have just been inflated/flattened to appear more threatening (defensive), and thus, either gender is possible (and therefore not necessarily a gravid female).

3:37 -- Where I talk about the rear fangs (and the Duvernoy's gland essentially, I just didn't mention per se), and in particular: the misbelief of "puncturing and deflating toads", I would like to provide an excerpt of greater elaboration, from Linda Krulikowski's amazing book: Snakes of New England:

"The [Duvernoy's] gland is composed of branched tubules rather than simple groupings of cells, and is situated immediately under the skin, above and near the angle of the jaw. It is derived from the same tissue as tooth enamel. The Duvernoy's gland opens by a duct at the base of the posterior, enlarged teeth. The secretions from the glands flow down the enlarged, rear teeth and into the prey, by the chewing motions of the snake. The secretions are introduced slowly into the victim, by indirect pressure from the nearby jaw-closing muscles (Green. 1997: 78-95). The secretions of Duvernoy's glands are colorless, whereas true [= Viperidae, Elapidae] venom glands secretions are typically some shade of yellow. These clear secretions immobilize the victim and help the snakes digest the prey."

"The secretions are introduced slowly into the victim, by indirect pressure from the nearby jaw-closing muscles (Green. 1997: 78-95)." This is where it looks like not just Heterodon, but also Thamnophis and Nerodia, as can be seen at the 5:09-10 mark (starts opening at 5:06), are "puncturing and deflating toads."

"These clear secretions immobilize the victim and help the snakes digest the prey." As stated in my video, this jaw-closing action is trying to immobilize the prey via injecting venom, but also to expedite/aid the digestion process.

Trivia Bit #1: Rear-fanged serpents are technically called opisthoglyphous, or in the case of a few genera such as Leioheterodon, aglyphous.

Trivia Bit #2: Nerodia spp. don't inject venom; they possess an anti-coagulant instead, which induces bleeding/prevents the wounds from clotting. Thus, the prey bleeds, and consequently 'faints', faster. Id est, it is still being immobilized.

5:34 -- Where I talk about the white [milky] substance, a toxin, produced by toads' parotoid glands to distaste, sicken or even kill would-be predators, which many other amphibians (including some newts) produce via different means, it is technically called Bufotoxin with Bufo spp., such as this B. americanus was producing against this Thamnophis sirtalis sirtalis.

Parotoid [alternatively, paratoid] vs. Parotid. It is technically the former with toads and other amphibians, but many sources will speak "parotid" which is actually a salivary gland in humans. This is an ongoing funny mistake by many authors and sources. Just a little trivia for You. And please excuse my mispronunciation; being a musician, I utilize "artistic license" on many words in Life. ;)

Thamnophis complex = North American Garter and Ribbon Snakes
Heterodon complex = North American Hognose Snakes
Nerodia complex = North American Water Snakes
(There are different genera of hognose and water snakes around the world, such as Madagascar Hognose Snakes (Leioheterodon) and South American Hognose Snakes (Lystrophis), and Eurasian Water Snakes (Natrix). There may be other Water and Garter/Ribbon Snake genera...?)

8:38 -- 'She is definitely on-guard.'

8:44 -- 'Wo, hey, [just] trying to get some footage of You, Girl.'

9:43/9:46 -- The white powdery substance on my (left) hand was the serpent's feces/musk.

10:18 -- 'Head scales' is quite commonly used; however, "plates", which consist of many differently-named groups around the head, is more proper. In Hognose Snakes of all three genera, they also have azygous scales which are situated immediately behind the rostral scale (the one which gives them their "Hog" nose), and which separate the internasals and prefrontals.

10:34 -- [Thamnophis] sirtalis sirtalis (shame on me for leaving out the actual genus name :P)

 
  Garter Snake Foreplay (Colubridae: Thamnophis sirtalis sirtalis)
Carl Barrentine
 
   
 
About

Published on Apr 14, 2012

Three smaller male Eastern garter snakes compete to seduce a larger, unresponsive female during an unseasonably warm and humid mid-April day. Photographed at Fisher, Minnesota (14 April 2012).

 

 

Camcorder

 
 
Visitor Sightings
 
           
 

Report a sighting of this reptile.

 
  This button not working for you?
Simply email us at info@MinnesotaSeasons.com.
Be sure to include a location.
 
  Lane Keller
9/12/2022

Location: Buffalo River State Park

This snake was hiding in the rocks next to the river where it was basking in the sun to start of the day off with hunting leopard frogs that were everywhere in the state park.

common garter snake

 
  Alfredo Colon
8/28/2022

Location: Albany, NY

common garter snake

 
  Alfredo Colon
8/11/2022

Location: Albany, NY

common garter snake

 
  Theodore Loftsgard
7/1/2021

Location: Rochester, MN

near my house in a trench under sod pieces. Relocated to Quarry Hill.

common garter snake  
  Marvin Gerald
6/15/2021

Location: Kandi Chippewa Line SE, Raymon, MN 56282

Sighting around 09:30AM with a live frog in its mouth among some cut tree branches on the ground. I startled it and it escaped into some nearby tall grass.

 
  Margot Avey
9/20/2020

Location: Westwood Nature Center, St. Louis Park, MN

This guy was big!

common garter snake  
  Kirk Nelson
5/23/2020

Location: Lebanon Hills Regional Park

common garter snake  
  Luciearl
5/8/2020

Location: Fairview Twp, Cass County

This garter sat very still so "I couldn't see it". Actually saw it very well and was able to take several photos. About 2 ft. long.

common garter snake  
  Jimmy Hultgren
4/27/2020

Location: Austin Minnesota, Mower County

common garter snake  
  Chris H.
4/19/2020

Location: Brainerd Northland Arboretum, Brainerd, MN 56401

After a record cold week, the sunshine finally warmed things up enough for some springtime sightings like pasque flowers and this little garter.

common garter snake  
  Robert Briggs
10/22/2016

I'm fairly certain this is a common rather than plains. Didn't get close enough with this picture - I had a wide angle lens on at the time.

common garter snake  
  Ida Marie
7/29/2016

I was in the bee balm photographing that red spotted purple butterfly yesterday and 4 and 1/2 feet off the ground this snake appears and scared the living day lights out of me....he had to be at least 3 feet long.

common garter snake  
           
 
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