California
Reptiles & Amphibians

Non-native Reptiles and Amphibians Introduced Into California

This is a list of non-native reptiles and amphibians which have been introduced into California and which have at one time established breeding populations, or which are suspected to be in the state. (AKA Invasive Species, Introduced Speces, or Exotic Species.) Most of these species have arrived recently, spread by humans either intentionally or accidentally. In some cases these established populations may prove to be only temporary and they will eventually die out. Released or escaped pet herps of almost any species are sometimes found in the wild, especially in heavily-populated areas, but these do not necessarily constitute an established population. The CA Dept. of Fish & Game has an Invasive Species Program. to prevent the spread of Invasive species and to reduce their negative effects. The intent here is to try to keep track of the introduced species which are the most common and widespread. There are no doubt more species which have become established in small areas in California which are not on this list. (An example would be a population of House Geckos I've seen living inside a pet store in Berkeley for many years. It is doubtful these geckos have invaded the rest of the neighborhood.) More species will probably become established in the state in the future, and some introduced populations will disappear due to competition, weather, disease, intentional eradication, or other causes. To see pictures of a few of the non-established non-natives which have been found in the wild, most likely former pets, see our page of Escaped Pet Herps. Please contact me if you find any population of non-native herps in the state that is not included here or is out of the range shown on our distribution maps.
Established and Breeding
Frogs
Rana berlandieri - Rio Grande Leopard Frog	Native to the southeast from the Atlantic to central Texas. Accidenatlly released near Yuma between 1965 - 1971, quickly spreading along the lower Colorado River area and the Imperial Valley. Range continues to expand.
Rana catesbeiana - American Bullfrog	Native to the eastern and midwestern United States and southeast Canada. Introduced for food in the 1920's by commercial frog farmers due to its large meaty legs. Now established throughout most of the western United States and soutwestern Canada.
Rana sphenocephala- Southern Leopard Frog	Most likely first introduced into the Santa Ana River basin in 1929 or 1930, probably as larvae that arrived with other imported Bullfrogs, fish, and crayfish from Louisiana. Now common in the Prado Flood Contro Basin.
Xenopus laevis - African Clawed Frog	Originally native to South Africa. Brought to the US in the 1940's and widely used as a standard amphibian for laboratory study and human pregnancy testing. A popular aquarium pet. Escaped laboratory animals and released pets were introduced into California primarily before being banned in the 1960s.
Salamanders
Ambystoma mavortium (tigrinum) mavortium - Barred Tiger Salamander Ambystoma mavortium (tigrinum) nebulosum - Arizona Tiger Salamander	Introduced into isolated locations in California, most likely through the introduction of released larvae used as fishing bait and expanding irrigation in arid areas.
Lizards
Hemidactylus turcicus - Mediterranean House Gecko	Native to the southern Europe. Spread rapidly throughout world, proabably through human transportation of its eggs in nursery shipments. A recent arrival in California, probably continuing to expand its range.
Tarentola mauritanica - Moorish Wall Gecko	Native to Mediterranean countries, found in isolated localities in California. Released or escaped pets are most likely the cause. Establishment of this species is still questionable.
Chamaeleo jacksonii xantholophus - Yellow-crested Jackson's Chameleon	Native to East Africa. In California, Jackson's Chameleons have been introduced into San Luis Obispo, Los Angeles, and San Diego Counties. (McKeown, 1997 Bull. Chicago Herpetol. Soc. 32:101.) Locations include Morro Bay, Laguna Beach, and possibly the Palos Verde Peninsula.
Snakes
Nerodia fasciata - Southern Watersnake	Native from the southeast west into central Texas. Established in and around Lake Natoma in the city of Folsom, Sacramento County, most likely from escaped or released pets. First documented in 1992 in Folsom. See: Stitt, Balfour, Luckau, Edwards - U.S.Fish and Wildlife Service Report, April 2005.
Nerodia fasciata - Southern Watersnake	According to Michael Fuller of the Nerodia Working Group, a reproducing population of N. fasciata has existed in Harbor City in Los Anageles for several years. While the snakes key out to N. f. pictiventris morphologially, preliminary mDNA results (as of 9/08) suggest that they are Nerodia clarkii, or possibly hybrids of N. clarkii and N. f. pictiventris. The habitat is a freshwater lake, typical of that used by N. fasciata, while N. clarkii typically inhabit brackish waters.
Nerodia sipedon - Northern Watersnake	According to Michael Fuller of the Nerodia Working Group, a population exists in the vicinity of Roseville, Placer County, which is fairly close to the Folsom population of N. fasciata.
*Consult the California Nerodia* website for more information about Nerodia found in California.** If you find a snake you believe to be a non-native watersnake, go to the site to find out where you can send pictures for confirmation.
Turtles
Chelydra serpentina serpentina - Eastern Snapping Turtle	Introduced into a number of isolated localities in the state, probably as a result of the release of pets.
Chrysemys picta bellii - Western Painted Turtle	Established in many locations in ponds throughout the state, especially in the south, probably as a result of the release of pets.
Trachemys scripta elegans - Red-eared Slider	Native to the south, and midwest, from eastern New Mexico, north into Chicago, and south to the Gulf Coast of Alabama and Georgia. Found throughout California. A common pet turtle. Released pets are largely responsible for the wide introduction of this species.
Apalone spinifera emoryi - Texas Spiny Softshell	Probably introduced into the Colorado River system around 1900. Now ranges throughout the Colorado River and the Imperial Valley and in other Isolated populations, including several locations in San Diego County.
Status in Doubt: Formerly Present, Now Unconfirmed
Snakes
Nerodia rhombifer - Diamond-backed Watersnake	This snake, native to the Southeast and farther south in eastern Mexico, was introduced to Lafayette Reservoir in Contra Costa County. First observed in the late 1980's, the population reached high densities in the early 1990's, bringing complaints from fisherman and other visitors who believed the non-native snakes were eating the reservoir's fish, frogs and turtles (which mostly consist of non-native stocked fish, non-native American Bullfrogs, and non-native Red-eared Sliders.) In 1996 contract was awarded to a wildlife control company to begin to control the snake population. Just as efforts were begun to increase the control effort in December, 1997, large numbers of dead watersnakes and turtles were observed. The cause of the die-off is unknown, but dissected snakes were found to contain a resperatory tract fungus. An especially wet and cold El Nino weather system has been suggested as a possible cause for the outbreak. No watersnakes have been confirmed at Lafayette Reservoir since late 1999, but sightings are occasionally reported, and the population may still continue to hang on in low numbers. Source: Stitt, Balfour, Luckau, Edwards - U.S.Fish and Wildlife Service Report, April 2005.
Lizards
Ctenosaura hemilopha - Spiny-tailed Iguana	According to Robert Stebbins in California Amphibians and Reptiles, 1972, this species, native to southern Baja California, was once present in Fullerton, but it's reproductive status was unknown.
Sceloporus cyanogenis (serrifer)- Blue Spiny Lizard	According to Robert Stebbins in California Amphibians and Reptiles, 1972, this species, native to southern Texas and northeastern Mexico, could be found at the base of the Palms to Pines Highway above Palm Springs, but whether or not it was established and breedidng was unknown.
Turtles
Gopherus berlandieri - Texas Tortoise	According to Robert Stebbins in California Amphibians and Reptiles, 1972, this species, native to southern Texas and northeastern Mexico, could be found occasionally in the desert where it was released as an unwanted pet.
Occurance of Established Populations Reported, but Not Documented and Confirmed. (Please contact me if you have any information.)
Many non-native herps have escaped into the wild in California. Alligators and Caiman occasionally show up in lakes and ponds and the press usually makes a big fuss over them. Most urban lakes contain a number of exotic species of turtles. (Jeff Lemm, in his Field Guide to the Amphibians and Reptiles of the San Diego Region, quotes biologist Mark Jennings, who has extensively surveyed Caifornia for reptiles and amphbians, as stating that ther are "roughly 30 species of exotic turtles found in southern California's waterways, although not all of these are established." I have been asked to identify herps that people find in their neighborhoods such as Milk Snakes, Corn Snakes, Boa Constrictors, Box Turtles, Bearded Dragons, and Blue-tongued Skinks. No doubt there are many more non-natives species loose in the state. But these are typically isolated instances and do not necessarily represent breeding populations, so they are not considered to be established non-native or exotic species, and they will not be listed here.
Snakes
Ramphotyphlops braminus - Brahminy Blind Snake (aka Island Blind Snake, Hawaiian Blind Snake, Flowerpot Snake.)	This tiny fossorial Asian snake has been introduced throughout the world in shipments of exotic potted plants, so it seems likely it will eventually show up in the state, especially in the south. The snake burrows into the soil and is not detected when the plants are shipped. This blind snake is parthenogenetic - all individuals are female and capable of bearing young, which allows for the spread of this species from just one individual. There have been unconformed reports from southern California, but these might be dark specimens of the very similar native Leptotyphlops Threadsnakes (Blindsnakes). I have seen pictures of them on fieldherping forums, however I have not seen any records of established breeding populations. However, it takes only one of these parthenogenetic snakes to create an established population.
Lizards
Anolis carolinensis - Green Anole	According to Jones, Lawrence, Rob Lovich, editors. Lizards of the American Southwest: A Photographic Field Guide. Rio Nuevo Publishers, 2009, a population of Green Anoles exists at the San Diego Zoo.
Anolis sagrei - Brown Anole	I have received a report of a population of this lizard in Palm Desert, but this has not been reliably confirmed.
Turtles
Geochelone pardalis - Leopard Tortoise	A population of breeding Leopard Tortoises has been reported at Mission Trails Park in San Diego County. These tortoises, originally from Africa, are common pets.

Return to the Top