FWC Adds Three Lizards to Florida's Dirty Dozen Invasive Species List

The Florida Fish and Wildlife Conservation Commission has refreshed its Dirty Dozen list of the state's most damaging nonnative species, adding three lizards in the iguana family and removing two species the agency now considers lower-priority concerns. The updated roster, announced earlier this year and reinforced in spring outreach materials, reflects the agency's effort to direct enforcement, research, and public education resources toward the species causing the most economic and ecological harm.

The three additions are the green iguana, the Mexican spiny-tailed iguana, and Peter's rock agama. All three are now established across portions of South Florida, with populations expanding northward as winters trend milder. FWC officials have removed two chameleon species and the Cuban tree frog from the priority list, noting that while those species remain present in the state, the highest-impact threats have shifted toward the larger iguana-family lizards and a familiar lineup of constrictor snakes, monitor lizards, and aquatic invaders.

The updated list arrives as Florida confronts a long-running invasive species crisis that has reshaped the Everglades, damaged residential infrastructure, and forced agencies to commit significant funding to capture and eradication efforts. More than 500 nonnative animal species have been documented in Florida, and dozens are established and reproducing in the wild. The Dirty Dozen designation does not by itself create new legal authority, but it signals the species the FWC considers priority targets for management.

The New Additions

The green iguana, native to Central and South America and the Caribbean, has become a familiar sight in canal banks, seawalls, and residential landscaping across South Florida. The lizards can reach six feet in length and several pounds in weight. They feed primarily on plants, including the ornamental flowering species that line many neighborhoods, and they dig burrows that can undermine seawalls, sidewalks, and the foundations of pools. During occasional winter cold snaps, the cold-blooded animals can become temporarily immobilized and fall from trees, an event the National Weather Service in Miami has periodically warned about.

The Mexican spiny-tailed iguana, also called the black spiny-tailed iguana, is somewhat smaller than the green iguana but is more aggressive and faster moving. The species has established populations in parts of the Tampa Bay region and the Florida Keys, with sightings increasingly common in coastal areas. The species can damage gardens, threaten ground-nesting birds, and burrow into structures. The species has been documented preying on the eggs of native sea turtles in some locations.

Peter's rock agama, a brightly colored lizard native to Africa, has spread rapidly through urban and suburban areas of South and Central Florida over the past two decades. Males display vivid orange and blue coloration during breeding season, making them visible additions to landscapes and parking lots. The species is highly mobile, climbs walls and trees, and has been documented in dense populations in some neighborhoods. FWC researchers have flagged concerns about competition with native lizards.

The Continuing Dirty Dozen

Several species remain on the list from earlier iterations, reflecting persistent threats that have not been resolved. The Burmese python, the most famous invasive species in Florida, continues to occupy the top of any discussion of Everglades wildlife management. The constrictor snakes, native to Southeast Asia, have established a self-sustaining population across the Everglades ecosystem and are widely blamed for the collapse of small mammal populations across South Florida wildlife management areas.

Nile monitors, large lizards native to Africa, remain a priority species. Populations are concentrated in the Cape Coral area and in parts of Palm Beach County, and the lizards are skilled predators of native wildlife, including ground-nesting birds and small mammals. The FWC and contracted hunters work to suppress Nile monitor populations through targeted trapping and removal programs, though the species' adaptability and intelligence make eradication difficult.

The list also includes nonnative fish species, including the lionfish, which has established itself across reef systems throughout the Caribbean and the southeastern United States. Lionfish are voracious predators of small reef fish and have reshaped reef ecosystems. Florida hosts annual lionfish removal tournaments that encourage divers to harvest the fish for consumption. Several invasive plants round out the list, including melaleuca, Brazilian pepper, and Old World climbing fern, each of which displaces native vegetation and alters habitat structure.

Why Iguanas Now Get Top Billing

The decision to add three iguana-family species reflects both expanding ranges and growing damage reports. Green iguana populations have exploded across South Florida over the past decade, driven by warming winters, the absence of natural predators, and access to abundant landscaping food sources. Property managers in coastal communities have reported significant repair bills for damaged seawalls, drainage systems, and landscaping, and homeowner associations have spent down reserves on iguana control contracts.

The damage profile is also expanding. While green iguanas were once considered primarily a nuisance to ornamental plants, recent research has documented impacts on native wildlife. The lizards consume the eggs of native nesting birds, and they compete with native herbivores for food. The species' burrowing behavior has been linked to the collapse of sections of canal banks in Broward and Miami-Dade counties, with repair costs running into the millions of dollars.

The agency's decision to elevate Peter's rock agama reflects how quickly the species has spread. First documented in Florida in the 1970s, the species was for years confined to a small area in South Florida. In recent decades, the lizards have appeared across South and Central Florida, with reports as far north as the Tampa Bay region. The species' ability to thrive in human-modified landscapes makes it particularly difficult to control.

What Removal Means

Removing the two chameleon species and the Cuban tree frog from the Dirty Dozen does not mean the FWC has abandoned management efforts for those species. The chameleon populations remain established but at lower densities and with more localized distributions, and the agency continues to monitor their spread. The Cuban tree frog, an aggressive predator that consumes native frog species and lays eggs in tiny pools of water around homes, remains a target of public education encouraging homeowners to humanely euthanize the frogs when found.

The agency periodically refreshes the list to reflect new science and to direct resources toward the most pressing concerns. The removal of species from the priority list signals a shift in attention, not an abandonment of broader invasive species management. The FWC continues to maintain a wider list of nonnative species under management, including hundreds of species with various levels of regulatory restriction.

The reshuffling also reflects how Florida's climate and ecology continue to change. Several species that were once limited by cold winters have expanded their ranges as the state has warmed. Researchers expect the trend to continue, with more tropical species establishing themselves further north in the state in coming decades. The agency uses periodic list updates to keep its management priorities aligned with on-the-ground reality.

How Homeowners Can Help

FWC officials emphasize that public engagement is critical to managing invasive species in Florida. Residents are encouraged to report sightings through the agency's iNaturalist project, the IveGot1 reporting system, or by calling the agency's Invasive Species Hotline at 888-IVEGOT1. Photos and location data help researchers track range expansion and population density, and reports of unusual species or sightings outside known range can lead to early intervention before populations become established.

For iguanas specifically, the FWC permits humane killing of nonnative iguanas on private property without a permit, subject to state animal cruelty laws that require methods consistent with the American Veterinary Medical Association's guidelines. Homeowners can also contract with licensed wildlife trappers for removal services, and several companies operate across South Florida specifically focused on iguana management. The agency cautions against poisoning iguanas, as poisons can also affect pets, native wildlife, and waterways.

Property-level prevention also matters. Removing dense brush, sealing burrow entries, installing physical barriers along seawalls, and avoiding plant species favored by iguanas can reduce the appeal of a property to invasive lizards. The University of Florida's Institute of Food and Agricultural Sciences publishes detailed guidance on landscaping choices and exclusion techniques, and county extension offices provide local advice tailored to specific neighborhoods.

The Python Question

While the iguana additions have drawn attention, the Burmese python continues to dominate Florida's invasive species conversation. The annual Florida Python Challenge, scheduled for 10 days in August this year, draws hundreds of participants to the Everglades to capture and remove the constrictors. Last year's challenge resulted in nearly 200 pythons removed, and the FWC awards prize money to top capturers in categories that include longest snake, most snakes, and novice participation.

The state also operates contractor programs that pay licensed python removal specialists to work in the Everglades year-round. The combined effort has removed tens of thousands of pythons since the programs began, but the snake's secretive habits and adaptation to the Everglades ecosystem make eradication unrealistic. The current goal is population suppression, particularly in areas where native wildlife is most at risk. Researchers continue to develop new detection technologies, including environmental DNA sampling and detection dog teams.

Importantly, the FWC and educational materials repeatedly distinguish among invasive species. A python is not an iguana, despite both being long, low-slung reptiles often photographed in Everglades settings. Different species require different management approaches, and confusing them can lead to misallocated resources or, in some cases, harm to native species mistaken for invaders. The agency's outreach materials emphasize species identification as a foundational skill for residents who want to help.

What's Next

FWC will continue its public outreach throughout the spring and summer, with workshops, social media campaigns, and printed materials designed to help residents identify and respond to invasive species. The agency's Exotic Pet Amnesty program, which allows residents to surrender unwanted exotic pets without penalty, will hold events across the state this year, providing a legal pathway for owners who can no longer care for animals like iguanas, monitor lizards, and large constrictor snakes. The program is designed to reduce the number of pets that are released into the wild.

The agency is also working with the Florida Legislature on potential regulatory updates that could affect the commercial trade in nonnative species. Recent legislative sessions have tightened restrictions on the import, sale, and possession of certain high-risk species, and additional measures could come in coming sessions.

Climate considerations will likely shape future invasive species policy. As Florida winters continue to warm, additional tropical species will likely establish populations across the state, and existing populations may expand northward into areas previously protected by occasional cold snaps. State universities and the FWC have ongoing research projects that model the future distribution of established invasive species under various climate scenarios, with results expected to inform management priorities in coming years.

For Florida residents, the message from FWC is unchanged: invasive species are a year-round responsibility, and the new Dirty Dozen list provides a clearer roadmap for where to direct attention as another long, hot summer arrives.