Creature Feature: Northwestern fence lizard

June, 2017

Sceloporus occidentalis occidentalis

Did you know that we have lizards that live in the redwoods? It’s true! The northwestern fence lizard (Sceloporus occidentalis occidentalis), a subspecies of the western fence lizard (Sceloporus occidentalis), roams the forests of the West Coast from Washington’s Puget Sound to the Mendocino Coast in California. Here in the redwoods, you may be able to find them in rocky outcroppings where the lizard can warm its body in the sun. 

The northwestern fence lizard is often called the “blue-belly lizard” because of the sparkling blue bellies on males. The blue color ranges from turquoise to a deep, almost navy, blue. Looking at the lizard from the top, you wouldn’t expect it to have a gem-like underside. The lizard is well-camouflaged, with sandy brown to black scales. Males are territorial and show off their bright blue bellies in a push-up like display to attract mates. They are not trying to build up their biceps!

Western fence lizard

Blue-bellies feed on insects such as crickets, ticks, and spiders, as well as other small lizards—including members of their own species! Blue-bellies have many predators, including spiders, snakes, and small mammals like feral cats and martens. 

Many kids have tried to catch a northwesten fence lizard; few have succeeded. The keen lizard is able to sense approaching threats thanks to a “third eye” on the top of its head that can sense changes in light, such as the shadow of an approaching child. If the lizard is caught by its tail, the tail may pop off and muscles in the tail will contract, causing the tail to flop around, thus distracting the predator (or kiddo) until the lizard can escape with a bobbed-behind. The tail will eventually regrow, but doing so takes a lot of energy. Remember, wildlife is best left wild! Don’t attempt to capture or catch wildlife, even if it is as cute as a blue-belly lizard.

A special protein in the lizard’s blood has been shown to cure Lyme disease. In California, deer ticks are responsible for the spread of Lyme disease and baby ticks are more likely to carry the disease than adults. When these baby, or nymphal, ticks suck the blood of a northwestern fence lizard, the bacterium that causes Lyme disease dies. Some have hypothesized that California has fewer reported cases of Lyme disease than the Northeast United States because of our healthy northwestern lizard population! 

How many other species like the blue-belly lizard contain life-saving secrets that we don’t know about yet? Preserving biodiversity is one means of preserving nature’s medicine.

Thankfully, neither the western or the northwestern fence lizard is threatened with extinction. If you look in the right places, we are practically rife with them. Their playful antics are worthy of a watch!