South Florida and invasive herps

Iguana iguana is invasive in Florida

South Florida is on the front lines in the war against invasive reptiles and amphibians because its warm climate makes it a place where they like to live, a new University of Florida study shows.

Using computer models and data showing where reptiles live in Florida, UF/IFAS scientists predicted where they could find non-native species in the future. They found that as temperatures climb, areas grow more vulnerable to invasions by exotic reptiles. Conversely, they found that extreme cold temperatures protect against invasion.

“Early detection and rapid response efforts are essential to prevent more of the 140 introduced species from establishing breeding populations, and this study helps us choose where to look first,” said Frank Mazzotti, a wildlife ecology and conservation professor at the University of Florida Institute of Food and Agricultural Sciences Fort Lauderdale Research and Education Center.

The new study is published online in the journal Herpetological Conservation Biology.

Lead author Ikuko Fujisaki, an assistant professor of wildlife ecology and conservation at the Fort Lauderdale REC, said scientists conducted the study to provide scientific data for managing invasive wildlife in the Sunshine State.

America imports more exotic animals than any other country in the world, with more than 1 billion animals entering the nation from 2005 through 2008, according to the U.S. Government Accountability Office. They come in by boats, planes and other modes of transportation. The animals are often used in the pet trade, but have other uses as well, including food and religious practices. Once they’re established, exotic animals are costly to remove, according to a 2010 led by Michigan State University. Therefore, wildlife management agencies are always looking for better ways to detect the invasive species early.

Urban areas are hubs of international transport and therefore are major gateways for exotic pests. With its subtropical and tropical climates and its high human population (19.9 million as of 2014), Florida provides a unique opportunity for a geographic risk assessment because of the number of exotic species that establish, fail to establish or whose fate is unknown, the UF/IFAS scientists said.

Invasive species are second only to losing habitats in contributing to the loss of biodiversity worldwide, Mazzotti wrote in a 2015 UF/IFAS Extension paper. Florida has more introduced species of reptiles and amphibians in the wild than anywhere else in the world.

This data leads Mazzotti to suggest South Florida as the focal area for exotic species.

“We need to focus immediate management efforts on South Florida, or invasive wildlife could jeopardize Everglades restoration,” Mazzotti said.

The authors add, “Since we created our list of target species, additional exotic herpetofaunal species have been introduced and become established in Florida. Some institutions in Florida, such as UFHerpetology, have been working toward accurately georeferencing occurrence locations in the state and make the data available online (https://www. or shared with other online databases such as GBIF and HerpNet ( Such data could be useful to further improve our predictions. Further, numerous imported exotic reptile species have not yet been observed in the wild but could be introduced through various pathways. Previous taxonomic risk assessments of exotic species have proposed various algorithms to predict potentially invasive species and have discussed their utility in invasive species management (Hayes and Barry 2008). Such assessments have been a part of the Australian national screening protocol for plants (Pheloung et al. 1999; Keller et al. 2007) and have been recommended for introduction as a part of invasive management practice in the United States (Lodge et al. 2006). Geographic assessments such as ours can be used to develop cost-effective management strategies by depicting spatial variability in habitat suitability for established, introduced, and imported species over wide geographic areas with variable environmental conditions.


Ikuko Fujisaki, Frank J. Mazzotti, James Watling, Kenneth L. Krysko, and Yesenia Escribano. Geographic Risk Assessment Reveals Spatial Variation in Invasion Potential of Exotic Reptiles in an Invasive Species Hotspot. Herpetological Conservation Biology, 2015; 10 (2): 621-632 

Archive by Month