Western Fence Lizard

The western fence lizard (Sceloporus occidentalis) is a successful reptile, readily adapting to human-altered environments and ranging over most of the American West.  It is perhaps the most well-known and commonly encountered lizard in California.  Western fence lizards, affectionately known as "blue bellies," are at home in a variety of habitats, from grasslands and woodlands, to farms and backyards, from sea level to over 10,000 feet.  They tend to favor habitats with access to water, and avoid deserts.

Western Fence Lizard (Sceloporus occidentalis) on a fence in the Central Valley
 A healthy population of curious western fence lizards resides in our garden, and we are happy to have them, as they prey on insects and spiders and are always entertaining to watch.

Being ectothermic, or "cold blooded," western fence lizards, like all reptiles, rely on energy from the sun to regulate their internal body temperature.  It is for this reason lizards are often seen sunning or basking on flat surfaces in the sun, such as rocks, logs, even the sides of buildings. 
Basking on a rock, near the Clark Fork of the Stanislaus River
                California's wide variety of habitats support six distinct subspecies of western fence lizard :

·         San Joaquin Fence Lizard (S.o. biseriatus) - Southern San Joaquin Valley

·         Northwestern Fence Lizard (S.o. occidentalis) - Northern Central Valley & Northwest

·         Coast Range Fence Lizard (S.o. bocourtii) - Central coast

·         Great Basin Fence Lizard (S.o. longipes) - Modoc Plateau, east of the Sierra, Transverse & Peninsular ranges

·         Sierra Fence Lizard (S.o. taylori) - southern Sierra

·         Island Fence Lizard (S.o. becki) - Channel Islands

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