Updated 2023

Let’s be honest, most people visit Bolsa Chica for the birds.  Don’t get me wrong, birds are great, I even studied them in school.  But Bolsa Chica is home to much more, and another group that usually gets ignored (unless it’s two males battling it out on the trail in front of photographers) are the reptiles.  

Some of the most common reptiles at Bolsa Chica that you might encounter are lizards and snakes.  Great Basin Fence Lizards (Sceloporus occidentalis longipes), also called blue-bellies, and Western Side-blotched Lizards (Uta stansburiana elegans) are the lizards that you see darting around the trails in front of you. The fence lizards are likely the ones you will see doing pushups on the fences, rocks, benches, you name it.  Side-blotched male lizards do it too but are usually found on the ground compared to the fence lizards.  There is some interesting research happening between fence lizards and Lyme disease carrying black-legged ticks or deer ticks.  One study shows that a protein the lizard’s blood kills the bacterium that causes Lyme disease, but when the lizard population is removed from a location the population of deer ticks also plummets.  So, is Lyme disease in human low in CA because of these Lyme disease fighting lizards, or do we still have Lyme disease in the state because the lizards are so common?  Kind of a chicken and the egg situation for human health. 

Side-blotched lizards have a dark spot right behind their elbows and their scales are smoother than the fence lizards. One neat factoid about side-blotched lizards is their mating strategies. Males ‘play a game of rock-paper-scissors.’ There are three different throat-colored types, and each type has a different method of getting the ladies. The orange throated males are the tough guys who defend territories and mate with any female they can get their claws on. The blue throated males form strong bonds with their females and defend the females against yellow throated males. They will also cooperate with other local blue throated males to defend their females from both other types of males. Yellow throated males mimic females to sneak in mating with females while the orange throated males are distracted fighting each other.  Orange-blue-yellow, rock-paper-scissors, each color has the advantage over one other color but not both.  

We’ve also started seeing more San Diego Alligator lizards (Elgaria multicarinata webbii) lately.  These lizards have super long tails and rather pointy heads. When it is mating season, males will bite down on a female’s head and hold on for hours at a time!  There is a citizen science project taking place at the LA Natural History Museum studying this interesting mating behavior.  You can learn more and contribute to their project by visiting ‘Look Out for Amorous Alligator Lizards.”

The Southern Pacific Rattlesnakes (Crotalus oreganus helleri) are the snakes that get the most publicity, but we also have San Diego Gopher Snakes (Pituophis catenifer annectens) and even CA Kingsnakes (Lampropeltis californiae).  Kingsnakes are known for actually eating rattlesnakes.  They are black with white or sometimes brown and white banded in coloration.  The rattlesnakes are the only pitviper at Bolsa Chica and uses special pits near their mouth to sense heat.  This helps them find their warm-blooded prey like rats and rabbits.  Interestingly, adult CA ground squirrels, like our Beechey ground squirrel, is actually immune to the venom.  Even though the gopher snake is not venomous, it will mimic the rattlesnake by curling up in the same and even rattle their tails in vegetation to make rattle-like sounds.

On occasion, another reptile, the East Pacific green sea turtle (Chelonia mydas), visits the waters of Bolsa Chica.  It’s rarer, but not unheard of and has become increasingly more frequently seen these last few years. This species is listed as threatened under the Endangered Species Act and is topic of important research and conservation efforts through NOAA Fisheries and other collaborating organizations.  If you see one, please report the sighting on their survey found on their Green Turtle Research and Conservation in Southern California webpage.

One lizard we are practically ‘fond’ of is the Southern CA Legless Lizards (Anniella stebbinsi) because they are so unique and a listed species.  These lizards are found on the mesa in the soil.  Most of the time when people see these lizards it is during our restoration events. Volunteers think the lizard is a small snake because, as the name implies, they do not have legs.  How do you tell the difference between this lizard and a snake?  Legless lizards have eyelids while snakes do not.  Subtle we know, but there you go.

Other reptiles that have been spotted in the area at one time or another are: Blainville’s Horned Lizards (Phrynosoma blainvillii), and Southern Western Pond Turtles (Actinemys pallida*).

To learn more about these reptiles visit: www.californiaherps.com

To learn which reptiles have special status in CA (updated July 2023) visit: https://nrm.dfg.ca.gov/FileHandler.ashx?DocumentID=109406&inline

*some differences between subspecies vs. species level acknowledgment between CDFW and californiaherps.com; see “Conservation Status” on California herps’ website for more details.

~Erin Chin

Video by Morgen Hansen