Reptiles of the Lowland Pacific Northwest

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Garter snakes

These snakes are a variable group, with  3 species and a couple of subspecies.  The best way to sort them requires counting the upper lip scales.  The lip scales are the row of scales just below the eye and above the mouth.  Obviously to do this requires actually holding the snake, something you might not want to go to the trouble of. To pick up a snake and avoid the snakes stinky secretion  you need to grab the snake in two places: towards the tail and behind the head. If you can accomplish this you will keep the snake from coiling itself around you and smearing its stinky defense. 

   

Puget Sound Garter Snake  Thamnphis sirtalis pickeringii

Identifying features:  Cream colored stripes, 7 upper lip scales.

There are two subspecies of T. sirtalis  more or less separated by the Columbia River. The northern subspecies, the Puget sound garter snake has cream colored stripes  The southern subspecies, the Red-spotted garter snake, Ts concinnus,  has a white upper stripe, reddish side spots and a dull reddish head.  It is found primarily in western Oregon.

These snakes are often found along grassy ponds or stream sides and they  readily take to water to escape. The young are born live in late summer, about a dozen are common, although a large female can have more than 50 young.  The young snakes eat mostly small invertebrates and worms, the larger snakes will eat frogs and other amphibians including the deadly poisonous Rough-skinned newt.  The snakes will spend the winter in groups called hibernacula, sometimes with other species of snakes.  They emerge in late March and often breed just as they emerge.  When threatened they emit a bad smelling acrid secretion which you do not want to rub in your eyes.

   
Northwestern Garter Snake  Thamnphis  ordinoides

Identifying Features:  Red stripes with 7 lip scales, the head is not much bigger than the body.

This snake has a wide variety of color patterns, and can be the most colorful of our garters. It can have side stripes of yellow, dark blue, green or with red flecks.  It is not often found around water which can help distinguish it from the Puget Sound garter snake. It is found in gardens, forest edges, clear cuts and roadside ditches.  Its diet is mostly slug, worms and beetles.  Up to 20 Young are born in the summer, and it will spend the winter in an underground den with a group of other snakes.

   

Western Terrestrial Garter Snake  Thamnphis elegans

Identifying features:  Often with a white or yellow upper stripe with dark vertical bars or spots on the sides.  8 upper lip scales.

This is snake most often found near water, especially in tall grass meadows near ponds.  It has a wide variety of color patterns so counting the lip scales is required to separate it from the other two species.  It eats whatever it can subdue, mostly invertebrates, occasionally eating small animals such as mice. It has a toxic secretion which it uses when it bites although it does not have fangs so a bite typically does not break the skin although it can cause a slight reaction.   It has similar habits of birth and hibernating as the other two species of garter snakes.

 

   
Rubber Boa  Charina bottae

Identifying features:  Olive green or greenish-brown snake with lighter underside, blunt tail.

This is our miniature version of the large tropical boas and it hunts small mice, nestling rabbits and nestling chipmunks which is subdues by constriction. It hunts mostly at dusk or at night.  It is found in a variety of habitats with cover but not too much shade, and often will burrow under leaves to spend the day.  It can be found under board piles or logs.  When threatened it will coil into a tight ball exposing its blunt tail which looks very much like its head, even striking out with its tail.  When it encounters a mouse nest the snake will use its blunt tail to strike at the defending mother mouse and often the tails of these snakes will show scars from these encounters.  Up to 6 Young are born live in the fall.

The rubber boa is not a commonly seen snake and may be declining in our area.

   
Northern Alligator Lizard  Elgaria coerulea

Identifying features:  Brown  to grayish lizard with dark bars or patterns on the side.

This lizard prefers open rocky habitats near forests such as rock piles in clear cuts, roadsides and old homesteads.  Occasionally they will inhabit wood piles. Young are born live during the summer, 4-8 young per female.  These lizards tend to stay under rocks or logs and forage in rock piles. They eat slugs, worms and almost any small invertebrate they can subdue. 

   
Western Fence Lizard  Sceloporus occidentalis

Identifying Features:  Long fingers on hind toes,  gray brown with triangular pattern on back, blue patch on throat and two blue patches on belly.

This is a lizard typically found in rocky open areas but can also inhabits rocky forest edges. In the Puget sound region it is found mostly on sunny south facing sandy hills or beaches. It is a predator, running and catching its prey mostly insects, with some worms and other small invertebrates.  The males have an interesting habit of doing "push ups", raising and lowering the upper part of their body to show off the blue underside, especially in April and May during breeding.

During early summer females lay 8-17 eggs in a shallow trench in loose soil. Eggs hatch in August and young of the year hunt until the weather cools enough to force them underground to hibernate.
   
Western Pond Turtle  Clemmys marmorata

Identifying features:  Dark green, brown or almost black turtle with fine yellow lines and spots on its head, larger yellow spots on the legs.

This turtle was once common and is now on the edge of extinction.  It is known from only a few locations in our area and recovery efforts have expanded its population slightly.  It is impacted by habitat displacement and diseases from introduced pet turtles, bull frogs eat the young and water quality declines. Basking sites, such as near shore logs are used  in early spring and are the most common place to see this turtle.   It is found on mud bottomed ponds, most often those surrounded by woods.  During the heat of summer the turtles will move into the cooler woods and often spend considerable time under old logs to stay cool.  Nests of up to a dozen eggs are dug in June and July on sunny south facing slopes, sometimes several hundred yards from the pond. Hatchlings emerge from the nest in the following spring, spending the winter in the nest.

   
Red-eared slider  Trachemy scripta

Identifying features:  Shell segments outlined in white,  Yellow stripes on head, red line behind ear.

This is the most common pet store turtle and it has been widely released into local lakes and ponds.  It is most often seen basking on near shore logs, sometimes in large groups, sometimes even stacked on top of each other in prime haul out sites.  They eat a wide variety of plants and the occasional insect or tadpole,  the young eat more invertebrates than plants.  Up to 30 Eggs are laid in sunny protected locations on lake shores in April and May.  Young hatch in July and August.  Other  introduced turtles include the Spiny Soft Shell and Painted Turtle.