Western Fence Lizards Have Lyme-Fighting Superpowers!


In springtime, western fence lizards to emerge from brumination (winter dormancy). These palm-sized reptiles have spent the colder winter months hiding lethargically under rocks, logs, and soil. They are now ready to gorge themselves on creepy crawlies and find love.

Western fence lizards, also called blue bellies because of the markings on the side of their abdomens, are the most commonly seen lizards in the Bay Area. Keep an eye out while hiking in the East Bay Regional Park District and you will often notice them sunning on paths, rocks, and fence posts. They range from tan to black, have sharply pointed scales, and the males can be seen doing “push-ups” to show off to potential mates.

Despite being inconspicuous, these little lizards have many extraordinary adaptations: they have a “quick release” tail and a third eye on the back of their head to help them escape from hungry predators. And, most notably, western fence lizards can cure ticks of Lyme disease!

This wonderful superpower is good news for California hikers. With the emergence of spring, tick nymphs (or teenagers) are on the prowl and looking for hosts to feed on.

Because they are no bigger than a poppy seed, these tiny parasites are difficult to spot and can spend more time on a human host, increasing the probability of transferring Lyme disease if they are carriers. Luckily, these ticks also love to feed on western fence lizards. If the ticks were infected with the Lyme disease bacterium, a protein in the lizards’ blood will cure the little blood suckers. With more blue bellies around, we see fewer cases of Lyme disease.

Turn Your Yard into a Western Fence Lizard Habitat
Make your outdoor space inviting to blue bellies by providing shelter and food to these helpful little reptiles. Large rocks and broken terracotta pottery can be used to hide and bask in the sun, while native plants and fallen leaves attract tasty insects like caterpillars, beetles, and grasshoppers. And remember to thank a blue belly next time you see one on the trail.

Watch a Western Fence Lizard video on our Digital Learning page.

Jen Vanya, Public Information Specialist