Thamnophis sirtalis Common Gartersnake
Some other names for this species:
Common Garter Snake
Subspecies I've seen:
T. s. concinnus
Red-spotted Gartersnake
T. s. fitchi
Valley Gartersnake
T. s. infernalis
California Red-sided Gartersnake
T. s. parietalis
Red-sided Gartersnake
T. s. pickingerii
Puget Sound Gartersnake
T. s. sirtalis
Eastern Gartersnake
T. s. tetrataenia
San Francisco Gartersnake
Thamnophis sirtalis concinnus Red-spotted Gartersnake
Tillamook Head trail, Ecola State Park, Clatsop County, OregonJuly 28, 2001
Red-spotted Gartersnake (Thamnophis sirtalis concinnus)
This brightly colored snake was sunning itself in the recently trimmed foliage alongside a steep trail that climbed up to a beautiful ocean lookout. I first saw it loosely coiled, about half covered by foliage, and I started getting my camera out. This must have spooked it into moving, and I was sad to miss a photo opportunity. But it resettled into this more photogenic position just a couple of feet away. Surprisingly, a medium-sized alligator lizard was revealed exactly where this snake had previously been. The lizard showed no signs of stress -- it seemed as if it had just been resting under the snake.

Just a few feet away was a garter snake of a different species. I keep seeing garter snakes of different species hanging out near each other.

Cape Falcon Trail, Oswald West State Park, Tillamook County, OregonJuly 1, 2015
Red-spotted Gartersnake (Thamnophis sirtalis concinnus)
I really should spend more time in the fairly small range of Thamnophis sirtalis concinnus, because they are often really beautiful. This little tyke is only the second one that I've seen.
Thamnophis sirtalis fitchi Valley Gartersnake
Bear Gulch Reservoir, Pinnacles National Park, San Benito County, CaliforniaJuly 7, 1999
Valley Gartersnake (Thamnophis sirtalis fitchi)
July is Sierran Treefrog season at Bear Gulch Reservoir. On this warm day, the water was thick with two- and four-legged tadpoles, and the shore was hopping with little froglets. The local gartersnakes had definitely noticed this frogging frenzy, as I spotted five of them in about an hour, all a quick slither away from the water.

Thanks to Sean Barry for correcting my misclassification of this snake. I had listed it as T. s. infernalis, but east of the Salinas river (as Pinnacles is) the gartersnakes are T. s. fitchi.

Bear Creek Trail, Pinnacles National Park, San Benito County, CaliforniaMarch 31, 2000
Valley Gartersnake (Thamnophis sirtalis fitchi)
This is the biggest gartersnake I've ever seen. I didn't measure it, but I guesstimated afterwards that it was nearly four feet long. The anacondas and pythons aren't impressed, but that's a mighty big gartersnake.

Thanks to Katie of natureid.blogspot.com for correcting my identification of this snake. I had originally misidentified it as Thamnophis elegans terrestris.

New River Area of Critical Environmental Concern, Coos County, OregonJuly 25, 2001
Valley Gartersnake (Thamnophis sirtalis fitchi)
My dog Max found this snake for me. I had walked passed it when Max started acting curious about something on the forest floor. This snake slithered a few feet from its original position and stared down Max, who was curious but not curious enough to get any closer.
Crane Prairie Reservoir, Deschutes County, OregonAugust 3, 2001
Valley Gartersnake (Thamnophis sirtalis fitchi)
This snake was one of three I saw at the same spot along the edge of the reservoir that I also discovered a wondrously large fat Western Toad. This snake had a half-swallowed tadpole or small fish in its mouth. This made swimming difficult for the snake, because its wide-open mouth would run into thin plant stalks, blocking its forward progress. This seemed to confuse the snake, which would push and push against the stalk rather than moving a half-inch to any side and trying again.
Bear Gulch Reservoir, Pinnacles National Park, San Benito County, CaliforniaMay 26, 2007
Valley Gartersnake (Thamnophis sirtalis fitchi)
This was one of several gartersnakes we saw swimming about in Bear Gulch Reservoir on this fine spring afternoon.
Bend/Sunriver Thousand Trails campground, Deschutes County, OregonSeptember 4, 2013
Valley Gartersnake (Thamnophis sirtalis fitchi)
A creek flows alongside this large campground in which we stayed for a few days. I took a couple of opportunities to poke around the creek trying to scare up a few herps. It was easy to scare up bullfrogs, and a little harder to scare up garter snakes. I saw a couple of adults, but only for an instant as they vamoosed. This tiny neonate stayed close enough for a few mediocre photos.
Bear Gulch Reservoir, Pinnacles National Park, San Benito County, CaliforniaJune 5, 2014
Valley Gartersnake (Thamnophis sirtalis fitchi) Valley Gartersnake (Thamnophis sirtalis fitchi) Valley Gartersnake (Thamnophis sirtalis fitchi) Valley Gartersnake (Thamnophis sirtalis fitchi)
I can usually count on finding a lot of Valley Gartersnakes near water at Pinnacles National Monument, but this day was even snakier than usual. In one circumnavigation of the reservoir I counted 50 of them, and I could easily have found more. Most of them were hanging out in the grasses and reeds at the edges of the water. But one large snake was in the shade of a boulder, slowly attempting to devour a reasonably large California Red-legged Frog. I say "attempting", because even though I watched it for nearly an hour, the snake had not yet figured out how to get those pesky front frog legs down its impressive maw.
Lake Como, Ravalli County, MontanaJune 27, 2014
Valley Gartersnake (Thamnophis sirtalis fitchi)
I found two species of gartersnake around this pond very near the campground in which we stayed for a few days with some friends. This was the only Thamnophis sirtalis I saw. I managed to get a few shots before it swam off, and only later when I reviewed my photos did I realize that it wasn't just another Wandering Gartersnake. The prominent stripe and flecks of red on the sides (only visible at higher resolution) give it away.
Lava Lake, Deschutes County, OregonJune 24, 2015
Valley Gartersnake (Thamnophis sirtalis fitchi)
While the rest of our camping group kayaked and paddle-boarded and hung out watching the kayakers and paddle-boarders, I went for a quick shoreline walk to see if any garter snakes would put in an appearance. This fine-looking fellow did so. I detained it long enough to get a few quick iPhone shots and to show it off to the generally-but-not-unanimously admiring group of camping buddies.
Thamnophis sirtalis infernalis California Red-sided Gartersnake
near Asilomar beach, Pacific Grove, Monterey County, CaliforniaFebruary 1, 2000
California Red-sided Gartersnake (Thamnophis sirtalis infernalis)
On sunny winter days just after rainy ones, gartersnakes come out to warm themselves along a path that runs between a creek and one of the famous Pebble Beach golf courses. I often see six or eight of them in a thirty-yard stretch. Most of them are Coast Gartersnakes, but a few of these beautiful red-sided ones are mixed in as well. It's rare to see two closely related snake species living so close together.
Fort Ord Public Lands, Monterey County, CaliforniaMarch 31, 2001
California Red-sided Gartersnake (Thamnophis sirtalis infernalis) California Red-sided Gartersnake (Thamnophis sirtalis infernalis)
The small snake in the first picture was hunting in a shallow pool. It saw or smelled us and lifted its head for a look around, but soon resumed a slow meandering swim.

The snake in the second picture was much larger and was located in the shade of the bushes at the side of a sandy trail where I see Blainville's Horned Lizards. It was a surprisingly long way away from any water. My dog Max was along for the hike and walked within a few inches of this snake without either taking notice of the other.

Cleone Lake, MacKerricher State Park, Mendocino County, CaliforniaJuly 18, 2001
California Red-sided Gartersnake (Thamnophis sirtalis infernalis) California Red-sided Gartersnake (Thamnophis sirtalis infernalis)
In the aquatic plants at a shallow edge of beautiful Cleone lake were a bunch of these small gartersnakes. I counted five in about 15 minutes of looking, but I'm sure I missed some.
Redwood National and State Parks Visitor Center, Orick, Humboldt County, CaliforniaJuly 23, 2001
California Red-sided Gartersnake (Thamnophis sirtalis infernalis)
Just outside the visitor center building is a short boardwalk wetlands trail leading to a lagoon overlook. My wife and I counted 9 gartersnakes along this short trail, though this is the only one that chose to pose rather than slithering off quickly.

This is very close to the border between the range of this subspecies and the range of T. s. fitchi, and the individuals here are most likely intergrades, with some characteristics of both subspecies.

near Aptos, Santa Cruz County, CaliforniaFebruary 17, 2002
California Red-sided Gartersnake (Thamnophis sirtalis infernalis)
This youngster was prowling about close to one of the few remaining breeding ponds of the endangered Santa Cruz Long-toed Salamander. Let us hope that the garter snake was dining on the local frog and common salamander population, and leaving the endangered ones alone.
Eel River, Humboldt County, CaliforniaOctober 19, 2003
California Red-sided Gartersnake (Thamnophis sirtalis infernalis)
I startled this very young snake on the pebbly shores of the Eel River. It slithered quickly into the water and to a nearby rock where it paused for photos. You can see the shed skins of damselfly larvae sharing the rock.
Fort Ord Public Lands, Monterey County, CaliforniaMay 15, 2005
California Red-sided Gartersnake (Thamnophis sirtalis infernalis)
This large California Red-sided Gartersnake had an especially bluish dorsal stripe and belly, reminiscent of the closely-related and highly endangered San Francisco Gartersnake.
Gold Bluffs Beach, Prairie Creek Redwoods State Park, Humboldt County, CaliforniaMarch 25, 2006
California Red-sided Gartersnake (Thamnophis sirtalis infernalis)
After a few rainy days, and a rainy morning in the redwoods, the sun finally snuck through the clouds in the early afternoon just after we arrived on the phenomenal Gold Bluffs Beach. I was off to look for salamanders, and wasn't really expecting to see any reptiles at all. I was pleasantly surprised to find this one snake basking at the edges of the bushes at the side of the road.

This area is apparently in an intergrade zone between T. s. infernalis and T. s. fitchi, and the snake here is probably not a "pure" example of either. The Humboldt Herps website has some discussion about the integrade characteristics gartersnakes in this area. Thanks to Katie of natureid.blogspot.com for pointing out that this individual perhaps looks more like T. s. fitchi than T. s. infernalis.

I never did see any interesting salamanders that day, but I did see one very fine frog.

Fort Ord Public Lands, Monterey County, CaliforniaSeptember 15, 2007
California Red-sided Gartersnake (Thamnophis sirtalis infernalis)
The herp pickings were slim on this not-too-warm late summer day as we took our dogs for a walk, but this one pretty gartersnake was out basking on the trail.
Thamnophis sirtalis parietalis Red-sided Gartersnake
Jackson County, MissouriMay 5, 2017
Red-sided Gartersnake (Thamnophis sirtalis parietalis)
My first Red-sided Gartersnake, and it barely has any red on its sides. What a disappointment! I could barely sleep that night.
Benton County, IowaMay 6, 2017
Red-sided Gartersnake (Thamnophis sirtalis parietalis)
Now that's more like it. This isn't a particularly colorful gartersnake (found crossing a gravel road), but at least it has some red on its sides.
Linn County, IowaMay 6, 2017
Red-sided Gartersnake (Thamnophis sirtalis parietalis)
This is one of a dozen or so gartersnakes our group found under rocks and boards. The boards in question had been placed there for the purpose of finding snakes under them later. So, job well done.
Holt County, MissouriMay 7, 2017
Red-sided Gartersnake (Thamnophis sirtalis parietalis)
My final Red-sided Gartersnake of this trip was also the prettiest.
Thamnophis sirtalis pickingerii Puget Sound Gartersnake
Deception Pass State Park, Island County, WashingtonJuly 6, 2015
Puget Sound Gartersnake (Thamnophis sirtalis pickingerii)
My wife and I and our dogs were in the Puget Sound area for a few days on a long road trip up to the Canadian Rockies and back, so naturally I hoped to see a Puget Sound Gartersnake. I was excited to see this reasonably large adult gartersnake slither across our path one morning, but on closer inspection it didn't look like the Puget Sound Gartersnakes I had seen pictured. The "classic" Thamnophis sirtalis pickeringii is very dark with a bluish or yellow-green vertebral stripe, and has flecking on the sides of the same color as the stripe. Also, this snake has 8 scales on the upper lip, which is normal for some gartersnake species but atypical for T. sirtalis (which usually has 7). So I wasn't really sure what species of gartersnake I had photographed until I put the question to a Facebook group. Thanks to Casey Lazik for assuring me that this is indeed T. s. pickeringii, whose appearance is more variable than I had realized.
Thamnophis sirtalis sirtalis Eastern Gartersnake
Lake Woodruff National Wildlife Refuge, DeLeon Springs, Volusia County, FloridaSeptember 19, 2001
Eastern Gartersnake (Thamnophis sirtalis sirtalis) Eastern Gartersnake (Thamnophis sirtalis sirtalis)
While looking for Dusky Pygmy Rattlesnakes with my friend Peter May and associates, we came across two garter snakes. The first pictured here is a large, old, thin, battle-scarred adult; it was under a palm frond. The second one is a healthy little juvenile; it was under a log. Neither of the two had any intention of sitting still for me to take pictures, and in both pictures here somebody is holding onto the snake's other end.

For more about the wildlife of Lake Woodruff, check out Dr. May's web guide to this refuge.

Janes Scenic Drive, Fakahatchee Strand State Preserve, Collier County, FloridaApril 4, 2004
Eastern Gartersnake (Thamnophis sirtalis sirtalis) Eastern Gartersnake (Thamnophis sirtalis sirtalis)
Janes Scenic Drive is a lovely dirt road winding through Fakahatchee Strand, a wilderness area full of swamp, epiphyte-laden cypress trees, and alligators. I got up early on the day after daylight savings began to drive east from Coral Gables to this natural wonderland. I wasn't sure if it was warm enough to be a good snake day. At the very start of Janes Scenic Drive, immediately adjacent to the Fakahatchee Strand Administrative Office, this charming gartersnake heralded the beginning of a nine-snake morning. I didn't see any other gartersnakes, but I saw two Everglades Racers and six Florida Watersnakes.

Thanks to correspondent Ervin J. "Buck" Kidd III, who taught me a little about the history and spelling of Janes Scenic Drive. He wrote: "Winford Janes (no apostrophes) was an early County Surveyor or County Engineer of Collier County, Florida, which was cleft from DADE County in the 1920's. Back then, the County Seat was at Everglades City. Naples was a remote fishing village and the Tamiami Trail was yet incomplete."

Elkmont Nature Trail, Great Smoky Mountains National Park, Sevier County, TennesseeMay 8, 2004
Eastern Gartersnake (Thamnophis sirtalis sirtalis)
Eastern gartersnakes range through more than a third of the U.S. and a good hunk of Canada too. Unsurprisingly, their colors and patterns can vary quite a bit through that huge range. This one was not particularly colorful, but I was still happy to see it, since I hadn't seen any gartersnake in over a month.
Snake Road, La Rue-Pine Hills Ecological Area, Union County, IllinoisApril 23, 2008
Eastern Gartersnake (Thamnophis sirtalis sirtalis)
This was probably the least interesting snake I saw in a few hours on the legendary Snake Road. At the time, I mistook it for a ribbon snake, but when I was looking through my photos later I realized what it was.
Chekika Day Use Area, Everglades National Park, Miami-Dade County, FloridaMarch 9, 2013
Eastern Gartersnake (Thamnophis sirtalis sirtalis)
Here's an early-morning snake soaking up heat from the sun and from an asphalt road.
near Everglades National Park, Miami-Dade County, FloridaMarch 23, 2013
Eastern Gartersnake (Thamnophis sirtalis sirtalis)
Jake Scott found this large, fat, pretty, and cooperative gartersnake under a board.
Thamnophis sirtalis tetrataenia San Francisco Gartersnake
San Mateo County, CaliforniaAugust 1, 2004
San Francisco Gartersnake (Thamnophis sirtalis tetrataenia) San Francisco Gartersnake (Thamnophis sirtalis tetrataenia)
This is one of the most beautiful of all North American snakes, and also one of the most rare. I had gone out looking for San Francisco gartersnakes to photograph many times, but without any luck. My friend Dan Singer figured out exactly where to look for them and discovered one on July 31. On August 1 he and Don Roberson and I revisited the spot and ended up sighting five. The two pictured above are the two that we got the best looks at; the other three slithered away quickly.
San Mateo County, CaliforniaJuly 31, 2005
San Francisco Gartersnake (Thamnophis sirtalis tetrataenia)
On a return visit to the same spot where I had seen San Francisco Gartersnakes the previous year, I found five adults and three little babies. This is one of the little babies, and it's the only one of the eight snakes that I could get a photo of. These snakes head straight into the water the instant they feel threatened.
San Mateo County, CaliforniaAugust 5, 2006
San Francisco Gartersnake (Thamnophis sirtalis tetrataenia)
Since my wife and I and our four dogs were passing nearby on our way up the coast to the giant South San Francisco dog park that is Fort Funston, I insisted that we stop by my favorite San Francisco gartersnake spot to briefly try our luck. We were not disappointed; we ended up seeing three adults including this one, and one tiny little baby. We also admired a highly defensive gopher snake in the area.
San Mateo County, CaliforniaAugust 19, 2006
San Francisco Gartersnake (Thamnophis sirtalis tetrataenia) San Francisco Gartersnake (Thamnophis sirtalis tetrataenia) San Francisco Gartersnake (Thamnophis sirtalis tetrataenia)
On this overcast Saturday my friend Fred Harer, his wife Angie, and I spent a few hours checking out the serpent population at our favorite San Francisco gartersnake hangout. Our reptilian bounty for the day consisted of the three youngsters pictured here, along with an assortment of Coast gartersnakes, numerous fence lizards and a pair of alligator lizards. We also saw the two frog species that San Francisco gartersnakes dine on most frequently, Sierran treefogs and California red-legged frogs.
San Mateo County, CaliforniaJuly 3, 2013
San Francisco Gartersnake (Thamnophis sirtalis tetrataenia)
After having not seen any San Francisco Gartersnakes in several years, I needed to try again. The first place I looked, my old standby, coughed up some Coast Gartersnakes, a Pacific Ring-necked Snake, and a young Western Yellow-bellied Racer, but no SF garters. I visited a second spot, and this young snake crawled across the path right in front of me.
San Mateo County, CaliforniaMay 4, 2014
San Francisco Gartersnake (Thamnophis sirtalis tetrataenia) San Francisco Gartersnake (Thamnophis sirtalis tetrataenia)
Some old and new herping friends were in the area on a gartersnake-targeting quest they called Thamnopalooza. I joined them for a couple of days, the first of which was spent looking for lovely San Francisco Gartersnakes. We found a bunch of them, including this cooperative one that we watched for 15 or 20 minutes as it prowled around looking for tasty snake treats.
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