We have two predominant lizard species here at Curbstone Valley, California (Southern) Alligator Lizards, and Coast Range (Western) Fence Lizards.
The Southern, or California Alligator Lizard (Elgaria multicarinata multicarinata) is the less common of the two species observed here, but still sighted relatively frequently during the warmer months.
This subspecies is endemic to California, ranging along the coast from Humbolt to Ventura county, and extending inland in the northern part of the range. They are found in grasslands, open forests and chaparral.
Alligator lizards have slender grey-brown colored bodies, ranging from 7-18 cm in length, with large heads and powerful jaws, with which they can inflict a nasty, and painful bite. Their limbs are short, but alligator lizards have long tails, sometimes as much as twice the body length. As with most lizards, they may detach their tail deliberately (caudal autonomy) as a defensive tactic. The tail will grow back, although generally not as perfectly as the original, and this is not without consequence. Tail regeneration is energetically expensive, and during regeneration, reproductive fitness and survival have been shown to be decreased.
Alligator lizards will hibernate in underground dens during cold winter months, emerging in early spring. Mating is thought to generally occur between April and May. Unlike some lizard species that engage in elaborate mating displays, alligator lizard males are more succinct. They simply pursue a female of interest, and mating ensues. As you can see below, I accidentally disturbed a mating pair this weekend seeking some privacy in one of our woodpiles.
We did apologize for the intrusion after capturing these photographs, covered them back up, and left them alone, as we’d love to see more of this species here on the property. This species is believed to lay eggs between May and July, with eggs hatching in late summer to early fall.
The diet of alligator lizards includes various invertebrate species, and occasionally young small mammals and birds.
On the farm, alligator lizards are also prey. I caught sight recently of this red-shouldered hawk (Buteo lineatus) outside the office window with the remains of an alligator lizard.
Just like snakes, alligator lizards shed their skin. As you can see below from another exciting wood pile find, they shed their skin in a single intact piece by essentially turning it inside out as they crawl out of it.
Proteins in the blood of both Southern Alligator and Western Fence Lizards have been shown to have a bactericidal effect on Borrelia burgdorferi, the causative agent of Lyme borreliosis (Lyme disease). As you can see from the pictures of the head of this male alligator lizard, we have no shortage of ticks, especially Western black-legged ticks (Ixodes pacificus), on this property during the spring months.
It has been shown that there is a lower proportion of adult Lyme-infected Ixodes pacificus than nymphal stage ticks in regions where these lizard species reside, and this is thought to be a result of the adult ticks feeding on these lizard species as nymphs.
Lyme bacteria reside in the gut of nymph-stage ticks, and the bacteria are believed to then be destroyed in the gut when the ticks feed on the blood of the lizards. This may help to account for a relatively lower incidence of Lyme disease in humans in regions where alligator and fence lizards are endemic. Just one of many reasons these lizards are valued residents of the farm.
We leave all wild animal species at Curbstone Valley in their natural environments, and are careful not to damage sensitive habitat and hiding places. Note that it is illegal to collect and possess native reptile species in California without the required licenses and/or permits.
 Kuo MM, Lane RS, Giclas PC. A comparative study of mammalian and reptilian alternative pathway of complement-mediated killing of the Lyme disease spirochete (Borrelia burgdorferi). J Parasitol. 2000 Dec; 86(6):1223-8
 Lane RS, Mun J, Eisen L, Eisen RJ. Refractoriness of the western fence lizard (Sceloporus occidentalis) to the Lyme disease group spirochete Borrelia bissettii. J Parasitol. 2006 Aug; 92(4):691-6.