Palm trees, beaches and lizards are all common to Florida’s landscape, but did you know not all lizards are native? In fact, University of Florida researchers tell us that there are three times the number of lizards in the Sunshine State that do not belong here naturally and are impacting various ecosystems and communities.
Peters’s rock agama, is a native to East Africa and known to grow as much as a foot in length. Scientists at UF’s Institute of Food and Agricultural Sciences (UF/IFAS) tell us this species is one that is not natural to Florida and has been spreading consistently since first documented. Chances are you already have come across the species in your own backyard even though it doesn’t belong.
“Getting moved by hitchhiking on vehicles, escapes and intentional releases of these lizards from the pet trade industry are the main culprits of their spread,” said Steven Johnson, a UF/IFAS associate professor of wildlife and ecology and co-author of a new publication on the species.
“People are seeing Peters’s rock agama in urbanized areas of Florida and they are very well-adapted to these locations,” said co-author Kenneth Gioeli, a natural resources agent at UF/IFAS Extension St. Lucie County. “An important takeaway to note about this species is that we do not call them invasive because they tend to prefer disturbed urbanized areas. Our human concrete jungle suits them.”
Gioeli and Johnson partnered to develop Peters’s rock agama in Florida, a comprehensive fact sheet detailing the traits, behaviors, as well as known and potential environmental impacts of the species in hopes that consumers will report them when spotted. The fact sheet is accessible from the UF/IFAS Electronic Data Information Source (EDIS), a single-source repository of all current UF/IFAS numbered peer-reviewed publications.
Here is what researchers know.
Peters’s rock agama were first introduced to Florida in 1976 via the pet trade. Additional research confirmed that the same reptile dealer was responsible for releasing the species in Homestead in Miami-Dade County and Palm City in Martin County and their range has been expanding ever since.
The species has “keeled” scales meaning ridged and tapering to a pointed tip, giving the lizard a rough-textured look. The scales on their tail, legs, and along the center of their back are prominent. They have wide, blocky heads, thin toes with claws, and long tails that do not easily break.
One of the most notable characteristics of the species is evident in the males’ colorful skin and relatively large size as compared to Florida’s native lizards. Adult males can grow to 12 inches including the tail, while females tend to be smaller. Adult males are boldly marked with an orange or red head, a black body, and a black-tipped tail immediately preceded by orange color when in breeding condition.
Breeding females carrying eggs differ from the males in that they have yellow or orange patches on their bodies. Other visible traits among females include brownish gray with light green spots and short stripes on their head and neck. Juveniles look like females.
“People have been known to do a double take because agama are so unusual,” Gioeli added. “Their large size, ability to scale buildings and trees, and the male’s characteristic red head are eye-catching. Fortunately, agama are not toxic, venomous or aggressive to people and typically flee when approached. This makes catching agama very difficult.”
Peters’s rock agama are carnivorous in their native range of East Africa, but have also been observed eating small mammals, birds, small reptiles, and vegetation such as flowers, grasses, and fruit.
The preferred domicile for these lizards is occupying residential neighborhoods. Currently, there is no observed evidence that they are invading natural habitats or competing with native species in the suburban areas for food and space, according to the publication. They do have the potential to negatively impact imperiled butterflies, especially in South Florida and the Keys.
“Although this lizard does not appear to be having much of a negative impact on Florida’s native species or ecosystems, it’s yet another example of the prominent role that the trade in non-native reptiles has played as introduction pathway in the Sunshine State,” Johnson said.
Much is a mystery surrounding these large lizards when it comes to economic, human quality of life and ecological impacts. For example, their diet in Florida has not been studied enough to determine if they feed on more than a variety of insects and small invertebrates.
Very little documentation exists on predators. Potential predators of Peters’s rock agama include hawks as well as reptile-eating snakes, such as the southern black racer, and feral cats. Smaller agama are at greater risk of predation than adults, and it is possible that large adult agama occasionally eat small ones.
“Research is on-going regarding the impacts of agama in Florida,” Gioeli added. “Issues such as the agama diet in Florida and reproductive behavior are in need of examination.
There is a likelihood they are eating young Cuban anoles which are another non-native reptile species. This begs the question “will agama be displacing Cuban anoles?”
UF/IFAS researchers and state agencies are trying to gain greater insight on nonnative reptiles and their distribution and impacts in Florida. It is important for people to report sightings of Peters’s rock agama and other nonnative reptiles and amphibians. It is particularly important to report them in areas where they have not been documented previously.
UF/IFAS researchers and Extension remind pet owners that it is unethical and against state law to release non-native animals in Florida so that they never release an unwanted exotic pet. The state of Florida operates an Exotic Pet Amnesty Program that helps people find homes for unwanted pet reptiles and other exotic animals. To learn more, visit the Florida Fish and Wildlife Conservation Commission’s Pet Amnesty website.
Becoming better educated about nonnative and invasive species is something all Floridians can do to help our native plants and animals.
“Residents can help as concerned citizen scientists by reporting a sighting of Peters’s rock agama using Eddmaps or the Ivegot1 mobile app for smartphones,” said Gioeli. “You will be prompted to get a user ID and password on both systems to report your sighting. If you see an agama, snap a photo of it and upload it to either of these reporting systems.”