It is quite common to mistake a lizard that has just lost its tail for dead! While unfortunately the lizard is now tail-less, it isn't dying, far from it actually. It is very much still alive. Lizards utilize caudal autotomy (tail dropping) as a survival strategy for predatory response! When being chased or spotted by a predator a lizard may drop his or her tail and speed away while the piece of tail continues to wriggle and squirm, mimicking another lizard. If a lizard is bit by a venomous snake it may drop its tail as well, to ensure that the toxin does not reach the rest of the lizard’s body. In some cases, the tail will even grow back, however the regenerated tail does have less function.
While helping out a volunteer planting event at Wunderlich Park, it was impossible not to turn over every piece of dried bark or large stone to inspect what was hidden below. Reptiles and lots of other critters love to hide underneath objects, especially in dry open areas like the one we were working in. While planting, another volunteer next to me lifted a small piece of wood and quickly dropped it, stunned by the squirming tail and tail-less lizard that he had found. After further observation, the small, dark brown, chunky lizard with yellow stripes down its body was identified as Plestiodon skiltonianus, or more commonly known as the Western Skink! While this lizard can sometimes be confused with a large Western Fence lizard (Sceloporus Occidentalis) or Southern Alligator lizard (Elgaria multicarinata) One of the distinguishing features on a juvenile Western Skink is it’s elongated bright blue tail! As the skink ages, the color usually turns to brown however some, retain the blue.
The skink we were observing had most likely dropped its tail in fear that we were predators. As we crouched down studying the skink, suddenly a smaller Sceloporus lizard skidded by, it was a great teaching moment to point out the significant differences between the two native lizard species. Sceloporus occidentatlis has the nick name “blue belly” because of the bright blue patches that line its underside. Springtime is a wonderful time to seek out your favorite reptiles and amphibians in San Mateo County, Happy Herping!
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