National Wildlife Federation/ San Diego County

Local Reptiles and Amphibians

by Deb Coon, Habitat Steward

Mention the word “reptile” and many people cringe. Yet reptiles and amphibians are fascinating creatures and most are harmless to humans; even the much-maligned rattlesnake has an important role in our local ecosystems. Reptiles help to control populations of rats and mice, other small mammals, and insects, while amphibians help to control insect populations, snails and slugs. Furthermore, reptiles and amphibians are typically shy creatures that avoid human contact when possible. Rattlesnakes, our only local venomous snake, are generally a danger only when threatened or taken by surprise. The best precaution one can take in order to avoid unpleasant encounters with them is alertness to one’s surroundings, which is probably good advice for anyone anywhere. The California Center for Wildlife’s book Living with Wildlife states that fewer than 1 in 34 million people will die of snakebite, which puts the chance of dying from snakebite at less than the chance of dying from a lightning strike (p.255).

Browse some of the websites listed below and learn to recognize the difference between venomous and harmless snakes so you won’t be needlessly fearful of the harmless ones. Rattlesnakes usually have arrowhead-shaped heads that are wide at the jaw, while non-venomous snakes typically have heads the same size as their bodies. We can accommodate lizards and snakes in our yards through plenty of vegetative cover, as well as rock piles for cover and rocks for sunning. While many reptiles are suited to our long dry season, most amphibians require constant sources of water/moisture due to their seasonal need to reproduce in water as well as their skin’s continual need for moisture.

Local Reptiles

The main categories of reptiles in San Diego County are lizards, snakes, turtles, and tortoises. In addition to several varieties of seaturtle, our primary indigenous turtle is the Western Pond Turtle; Snapping Turtles, Red-eared Sliders, and Spiny Softshell Turtles have been introduced. Desert Tortoises are found primarily in the eastern desert portions of the county, as their name suggests.

Among the lizards of our county are the relatively common Western Fence Lizard, Southern Alligator Lizard, and Side-Blotched Lizard. There are seven species of our lizards listed as protected or sensitive: California Legless Lizard, Coastal Banded Gecko, Leaf-Toed Gecko, Coast Horned Lizard (once common), Southern Sagebrush Lizard, Western Skink, Orange-throated Whiptail, Coastal Western Whiptail, and the Granite Night Lizard.

Several local species of snake are federally listed as sensitive or protected. These include the Southern Rubber Boa and Coastal Rosy Boa, the Western Ringneck, Coast Patch-nosed Snake, Two-Striped Garter and California Red-Sided Garter snake, and the Red Diamond Rattlesnake. Of these, only the Red Diamond Rattlesnake is venomous. [Reference for information on reptiles: http://www.werc.usgs.gov/fieldguide/list.htm.] Snakes suffer the greatest danger from automobiles, habitat destruction, and fearful humans who kill them unnecessarily.

The San Diego Natural History Museum sums up the public relations problem for snakes this way: “Because of widespread negative attitudes towards snakes, very few conservation programs, worldwide, have been created. A much higher percentage of snakes are threatened with extinction than is currently recognized. Therefore, snakes are particularly susceptible to being overlooked by conservation-minded biologists” (http://www.sdnhm.org/fieldguide/herps/lich-tri.html).

[Sources for this section included the websites cited above as well as the California Center for Wildlife’s book Living with Wildlife (1994).]

Local Amphibians

Salamanders, newts, frogs, and toads are all found in San Diego County. Several species of salamander dwell in our mountains and riparian areas, where they can find the conditions of constant moisture they require. A small salamander called the Garden Slender Salamander is sometimes found in gardens, but only in very moist conditions. The California Newt is considered a California species of special concern, and the Large-blotched Ensatina (a salamander) is listed as both a federal and California species of special concern.

Among our more common local toads and frogs are the Pacific Treefrog, the California Treefrog, and the Red-Spotted Toad. The Pacific Treefrog is the most common of the three, found in a wide variety of habitats from the sea coast to inland chaparral and grasslands, to mountainous areas. Among the federally protected or sensitive species are the Arroyo Toad, and the Western Spadefoot Toad. The Spadefoot Toad is a fascinating species whose life cycle depends on the brief existence of the vernal pools once found throughout our region. Vernal pools are small pockets of water that form in depressions after our heavy winter rains; they are unique to areas with poorly draining soil due to clay or sandstone substrate. Spadefoot toads mate, lay eggs, hatch into larvae and mature to adults within the short span of ten to twelve days. They then burrow into the mud of the vernal pools and “estivate” during the long dry season until the next winter’s rains penetrate the soil, when they dig their way back out to begin their life cycle anew. [See Ancinec, Radford and Schwenkmeyer’s Natural History of Southern California: A Laboratory Guide, for further information on the vernal pool ecological community as well as other habitat communities found throughout San Diego County]. Habitat loss through urbanization and agriculture is primarily responsible for the decline of these amphibian species.

Web Resources to Learn More about our Reptiles and Amphibians

SD Nat?’l History Museum?’s Field Guide to Reptiles and Amphibians
SDNHM's Checklist of Amphibians in S.D. County
SDNHM's Checklist of Reptiles in S.D. County
Information on CA Reptiles and Amphibians
SDNHM's FAQ page about rattlesnakes
Western Ecological Research Center of the USGS
Frog Watch, run by NWF and US Geol. Survey
Society for the Study of Amphibians and Reptiles
San Diego Turtle and Tortoise Society website
San Diego Herpetological Society