By Tanisha Randhawa
Does a lizard whose blood cures Lyme disease-carrying ticks even exist? Yes! It’s called the Western Fence Lizard and it just so happens that when a young, infected tick feeds on this type of lizard, it grows up to become disease-free.
The Western Fence Lizard can be found sun bathing on paths, rocks, fence posts, and other high areas. This reptile is also known as the ‘blue-belly’ for its characteristically blue abdomen. However, this distinguishing trait is often faint or absent in females and juveniles and more regularly occurs in the adult males.
The general appearances of Western Fence Lizards are sandy or greenish brown to black in color with black stripes on their backs. They tend to have yellow side limbs with blue patches on their throats. Blue-bellies are typically about 8 inches long from their snouts to the tips of their tails and can also be recognized by their sharply overturned scales.
The Western Fence Lizard can also be called by its scientific name, Sceloporus occidentalis. It belongs in the Squamata order, which includes all lizards and snakes as ‘scaled reptiles’. Its suborder is Iguania and its family is still under debate, but it is often classified under Iguanidae.
Although blue-bellies consider California the heart of their home range, they can also be found in eastern and southwestern Oregon and even as north as Seattle, Washington for some populations. Additionally, Western Fence Lizards have formed habitats in southwestern Idaho, Nevada, western Utah, and Arizona. They are found in areas of grassland, broken chaparral, sagebrush, woodland, coniferous forest, and farmland. These reptiles occupy elevations from sea level to 10,800 feet although they usually avoid the harsh desert. Currently, blue-bellies are listed as unprotected and no conservation restrictions apply.
Since Western Fence Lizards spend much time lying freely in the sun, they are easy targets for predators such as birds and mammals, including shrews, relatives of moles that look more like long-nosed mice. For protection, they depend on employing their quick reflexes, which are common in many lizards. Blue-bellies’ diets are comprised of spiders and insects such as beetles, mosquitoes, and various species of grasshoppers.
Similar to the behavior of other lizards, S. occidentalis goes through a period of hibernation during the winter season. Depending on the climate, the length of time and when they emerge varies. Blue-bellies mate during the spring season, and do not breed until their second year. During the mating season, the adult males will defend a home range. Between April and July, the females will lay 1 to 3 clutches of anywhere from 3 to 17 eggs, although the number of eggs is typically around 8. Then in August, the eggs hatch.
Studies have shown that the number of cases of Lyme disease is lower in areas that house Western Fence Lizards. This is due to the fact that ticks carrying the disease feed on the reptiles’ blood, which they usually do, especially around the ears. A protein in their blood kills the bacterium that causes the Lyme disease, which results in the cleansing of blood inside the ticks’ systems so that they no longer carry the disease.
The next time you’re taking a stroll down the Richmond Greenway or enjoying the shade of the trees, keep your eye out for the sun-loving blue-belly.
“Western fence lizard – underside” by Linda Tanner – Flickr: Leapin’ Lizards!. Licensed under CC BY 2.0 via Wikimedia Commons
“Sceloporus occidentalis” by Calibas – Own work. Licensed under CC BY-SA 3.0 via Wikimedia Commons
NW Fence Lizard [Adult female] McCloud River [Siskiyou Co.] Aug, 23, 2008