In 2020 I was visiting friends in southern Florida. They picked me up at the Fort Lauderdale-Hollywood International Airport, and within a few minutes, we were headed south. Looking out the car window, I was astonished to see a Brown Basilisk Lizard, Basiliscus vittatus, trying to walk across the freeway. The lizard was a species I had photographed in Belize and Costa Rica. It was also a species I had kept as a pet in elementary school. Gioeli et al. (2022) suggest the Brown Basilisk was introduced into Florida through the pet trade, and they were first observed in the wild in 1963. Therefore, they are considered an established non-native species. In February 2022, the Florida Museum of Natural had 160 voucher specimens.
But the Brown Basilisk is just one species of 70 established in Florida. As a result, the Sunshine State has more non-native lizard species than native species. Many, if not all, of these species, are established, but few seem to interact with the native species. An exception is a hybridization between the native Green Anole, Anolis carolinensis, and the morphologically similar alien, the Cuban Green Anole, Anolis porcatus, in south Florida (DeVos et al. 2022).
Another species that likely negatively impact the Florida fauna is the Argentine Black and White Tegu, Salvator merianae, an omnivore that eats fruits, vegetables, eggs, insects, and small animals. As a predator, the tegu is likely to have harmful effects on south Florida’s native wildlife. In diet analysis of 124 tegus captured along the urban edge in Miami-Dade County, 39% contained vertebrate remains. These included frogs, toads, lizards, snakes, turtles, and small mammals. The discovery of Gopher Tortoise hatchlings, Gopherus polyphemus, in the guts of five tegus from central Florida confirms their threat to imperiled and protected species in Florida (Harvey et al. 2021).
The Northern Curlytailed Lizard, Leiochephalus carinatus, is continuously distributed along the Atlantic coast in Palm Beach County and northern Broward County (Smith et al. 2004) and was observed in some scrub preserves. This non-native species, which is substantially larger than the imperiled and native Sceloporus woodi, could become a significant competitor or a predator of hatchlings (Enge et al. 2021).
The Florida list goes on. Arizona is another story. The state has six species of invasive lizards. Three geckos , (Tarentola, Hemidactylus, Cyrtopodion), a whiptail (Aspidoscelis), a skink (Chalcides), and an iguanid (Ctenosaura). All of these are established none of them appear to be impacting native lizards, The reason for this may be the xeric conditions of Arizona or the higher temperatures but it is more likely related to the lower human population 7.2 million in Arizona, compared to Florida’s 21.1 million. Therefore fewer people keep exotic species as pets. An even more like cause seems to be Florida is the center for importing animals for the pet trade, Arizona has few animal importers.
To the left from the top: Brown Basiliscus Lizard, Mediterranean Gecko, Giant Day Gecko.
Literature
DeVos T, D Bock, J Kolbe. 2022. Rapid introgression of invasive alleles following hybridization between a native Anolis lizard species and a cryptic invader across an urban landscape. Authorea Preprints. 2022 Mar 13.
Enge KM, Tornwall B, Bankovich B. A Status and Distribution of the Florida Scrub Lizard (Sceloporus woodi). Herpetological Conservation and Biology. 2021 Aug 1;16(2):281-94.
Gioeli KT, SA Johnson, A Thompson. 2022. Brown Basilisks in Florida: WEC/452/UW497, 8/2022. EDIS 2022, no. 4 (2022).
Harvey RG, Dalaba J, Ketterlin J, Roybal A, Quinn D, Mazzotti FJ. 2021. Growth and Spread of the Argentine Black and White Tegu in Florida: WEC347/UW482, 6/2021. EDIS. 2021 Sep 23;2021(5).
