Thursday, June 4, 2015

Grassland Snakes of the Santa Cruz Mountains

Special guest at today's volunteer project    
Today at a volunteer project, I am making a lunchtime presentation about snakes commonly found in grasslands of our local Santa Cruz Mountains in the central coast of California.

Western yellow-bellied racers demonstrating the periscope and the laid-back techniques for
finding prey in dense litter.   
Here's my notes. I'll let you know how the project and the presentation went.

Blotchy coloration of a juvenile western yellow-bellied racer on Skyline Ridge Open Space Preserve.
Has the large racer eyes.   
Western yellow-bellied racers are the quintessential grassland snake in our area. They are the sorta-brown sorta-green streak you see dashing between the grass stems. They have large eyes and often "stand up" to look around.  If you are lucky enough to get close, you might see the soft butter yellow color of their underside. Young yellow-bellied racers start out with brown blotches on their back and sides - it's unusual for juvenile snakes to have a different coloration than the adults (The Curiosity of Racers).  I occasionally see racers swimming among the branches of coyote brush, the most common shrubs that pop up in our grasslands.

Gopher snake on Skyline Ridge Open Space Preserve   
Pacific gopher snakes are the most common brown-blotched snake in our grasslands. They can get to be several feet long but still retain an overall slender body shape with glossy color. Often hunting rodents, you might see them slipping in and out of burrows or sunning on a dirt trail. I've notice many gopher snakes on the Dipper Ranch have peach-colored bellies. You can distinguish them from rattlesnakes by the narrow sharp-pointed tail, head only slightly wider than neck, and round pupil (see more details with photos comparing gopher snakes to rattlesnakes at Buzzer Gets Its Color).

Northern Pacific rattlesnake on Russian Ridge Open Space Preserve   
Northern Pacific rattlesnakes are the only venomous snakes in our region that can be harmful to humans. They have brown blotches narrowly outlined by white and the last few inches of the tail have dark rings before the rattle. Their head is broadly triangular and much wider than the narrow neck. Their pupils are slits. Today, as at every volunteer project in grasslands, we will review how to be careful around rattlesnakes.

Any snake you see in the grasslands with long stripes down its length is probably one of the many species of gartersnakes.  Not "garden" snake, but "garter" snake because their long stripes reminded someone of the old-fashioned striped garters or suspenders used to hold up pants or socks. Gartersnakes are often seen in or near water.

Santa Cruz gartersnake at Monte Bello Open Space Preserve   
Santa Cruz gartersnakes are blackish with one long yellow stripe down the middle of the back.

Coast gartersnake on Skyline Ridge Open Space Preserve   
Coast gartersnakes also have a blackish background and a dark head but with more stripes - one wide yellow stripe down the middle of the back, another light stripe along each side, and red and black checkerboard blotches on the sides between the stripes.

Kingsnakes are banded - with wide rings going around their body rather than down its length.

California kingsnake on Los Trancos Open Space Preserve.
This juvenile snake was being harassed by a Stellar jay.  
The California kingsnake is two-toned.  Bands of white separated by bands of black or brown. They eat a wide variety of prey including snakes and are immune to rattlesnake venom. I don't see California kingsnakes very often in the Santa Cruz Mountains but others do.

California mountain kingsnake on Skyline Ridge Open Space Preserve   
California mountain kingsnakes have bands in three colors - black, white and red. Despite these bright colors that one might assume mean danger, they are not venomous. Field guides usually describe California mountain kingsnakes as occurring in rocky areas of forests and brushy habitat, however, I find them in grasslands of the Dipper Ranch, so I've included them in this local grassland snake primer. Earlier adventures with California mountain kingsnakes can be found here: Scales on My Sleeve,  A Cheerful Disposition, and Vote for the 2013 Walnut Label.

There are other snakes that can be found in grasslands of the Santa Cruz Mountains, but these are the ones most commonly seen.

A California mountain kingsnake will be making a guest appearance with me today at my lunchtime presentation for the volunteer day at Los Trancos Open Space Preserve.  We will be spending a few hours pulling the few remaining invasive yellow starthistle plants out of the Los Trancos grasslands. At Midpeninsula Regional Open Space District, we believe that volunteer projects are just as much about the experience of being outdoors as they are about getting work done. Since I just rescued this lovely snake from the Dipper Ranch springbox, I figure it can teach the volunteers about some of the local wildlife species and thank them with its colorful loveliness for restoring the native grassland.

If you are interested in other unique volunteer experiences in local preserves, check out the upcoming volunteer projects on the newly designed Midpen website here. I can't promise a friendly snake guest at every Midpen volunteer event, but there's always something interesting and fun to learn outdoors.


The volunteer day went great. We pulled widely scattered yellow starthistle plants in two meadows of Los Trancos. The quiet task of weed pulling provides the chance to strike up a conversation with a new friend and gives one intimate glances of the small critters that live in grasslands. The volunteers seemed to enjoy the lunchtime stories and photos of grassland snakes and, after some initial surprised responses, everyone enjoyed meeting the calm and handsome California mountain kingsnake. We are starting to test the new Weed Manager tool on Calflora - reports of our work on these two meadows can be found here as poe 2574 (plant observation entry) and poe 2575.



Western Yellow-bellied Racer,  Coluber constrictor mormon

Pacific Gopher SnakePituophis catenifer catenifer

Northern Pacific RattlesnakeCrotalus oreganus oreganus

Santa Cruz Gartersnake, Thamnophis atratus atratus

Coast Gartersnake, Thamnophis elegans terrestris

California Kingsnake, Lampropeltis californiae

California Mountain Kingsnake, Lampropeltis zonata


  1. Lovely. I'm envious of your audience. =)

    This is probably too obscure for your talk, but it can be fun to talk about the variability of patterns in herps (& other things), including the striped morphs of kingsnakes (v. banded):

    Also, are you going to teach the peeps the "Red touches black, good for Jack, red touches yellow, dangerous fellow" thing? =) Makes me feel like a pirate every time I go over it in my head. V. handy, though. You've got some LOVELY shots of some beautiful snakes. Nice work. =)


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