Invasive Lizard Species in Florida to Know About

Florida has more established invasive reptile species than any other state in the country, and several of them are large lizards that are spreading rapidly through urban and suburban areas. 

Whether you are a homeowner dealing with iguanas in your yard, a landscaper who just spotted a four-foot tegu on a jobsite, or simply a Florida resident trying to understand what is happening with the state's wildlife, here is what you need to know.

Why Florida Has So Many Invasive Lizards

Florida's subtropical climate is ideal for reptiles. Warm temperatures year-round, abundant food sources, and extensive natural areas create conditions where non-native species introduced through the pet trade can establish breeding populations and expand their range. 

Florida has more non-native reptile species established in the wild than anywhere else on earth, including over 30 species of non-native reptiles, amphibians, and other wildlife.

Most invasive lizard introductions trace back to the pet trade: animals released deliberately by owners who could no longer care for them, or escaped from facilities. Once a population reaches breeding density in a suitable habitat, control becomes extremely difficult. 

Several species that were once considered isolated problems in South Florida have now established populations across multiple counties and continue to expand northward.

The Main Invasive Lizard Species in Florida

Argentine Black and White Tegu (Salvator merianae)

The Argentine black and white tegu is among the most ecologically concerning invasive lizards currently established in Florida. Adults grow to over four feet in length and can weigh more than 15 pounds.

They have a striking black-and-white banded pattern on their body and tail, with bright green heads as hatchlings that fade after their first month.

Tegus are omnivores and opportunistic feeders that consume a wide variety of prey, but their particular threat to Florida ecosystems comes from their appetite for eggs. They actively prey on the buried eggs of native species, including sea turtles, American crocodiles, gopher tortoises, ground-nesting birds, and burrowing owls. 

Research from USGS has documented tegus raiding alligator nests and turtle nests, threatening species already under conservation pressure.

Established breeding populations currently exist in Miami-Dade County, Hillsborough County, Charlotte County, and St. Lucie County. Their range is expanding. The FWC banned the import, sale, and possession of tegus in 2021 as part of new rules targeting high-risk invasive reptiles.

If you see a tegu, the Florida Fish and Wildlife Conservation Commission (FWC) asks that you report it to the Invasive Species Hotline at 888-IVE-GOT1 (483-4681) or online at IveGot1.org.

Green Iguana (Iguana iguana)

Green iguanas are the most widespread invasive lizard in Florida and are found throughout the southern and central portions of the state. Adults typically reach 4 to 5 feet in length. Despite their size, they are primarily herbivores that consume vegetation, flowers, fruit, and leaves.

Green iguanas' most significant damage to human infrastructure comes from their burrowing behavior.

They excavate burrows under foundations, seawalls, sidewalks, and levees, creating structural undermining that can be expensive to remediate. In waterfront communities, iguana burrows in seawalls and canal banks are a persistent and costly problem.

They are also significant pests in ornamental gardens. Iguanas consume a wide variety of landscape plants and can strip garden beds rapidly.

Unlike tegus and monitors, green iguanas are so widespread that the FWC does not require them to be reported. Homeowners on private property are allowed to remove iguanas from their own land using humane methods.

Nile Monitor Lizard (Varanus niloticus)

Nile monitor lizards are large, predatory lizards native to Africa. Adults can reach six feet or more in length and are powerful swimmers. An established population exists in Palm Beach County, centered in and around Cape Coral and West Palm Beach areas.

Nile monitors are formidable predators that consume birds, small mammals, fish, and eggs. They are a significant threat to native wildlife and have been documented raiding nests of burrowing owls and other ground-nesting species. Unlike iguanas, monitor lizards are not herbivores and pose a more direct predatory threat to native fauna.

Nile monitors should be reported immediately to FWC's invasive species hotline if encountered. They are a priority reporting species.

Gold Tegu (Tupinambis teguixin)

Gold tegus are somewhat smaller than Argentine black and white tegus, averaging 2 to 3 feet as adults. Evidence suggests established or breeding populations in Miami-Dade County.

Like the Argentine tegu, gold tegus are omnivores with a documented preference for eggs, making them a similar ecological threat to native ground-nesting wildlife.

Spiny-Tailed Iguana (Ctenosaura similis)

Spiny-tailed iguanas are black-and-white banded lizards that are somewhat smaller than green iguanas and significantly faster. They are primarily herbivores but will consume insects and small animals.

Established populations exist in several South Florida counties. Their burrowing behavior causes some of the same infrastructure concerns as green iguanas.

Ecological Threats of Invasive Lizards

The threat posed by Florida's invasive lizard community extends beyond property damage. The ecological impact is outlined in the table below.

How to Prevent Invasive Lizard Problems on Your Property

1. Exclude food sources. Iguanas are attracted to fruiting plants, flowers, and vegetable gardens. Remove fallen fruit promptly, protect garden beds with barriers, and consider replacing iguana-attractive plants near your foundation with species they find less palatable.

2. Seal and protect burrow sites. Iguanas burrow in loose soil near water and near sunny, open areas. Hardening soil surfaces and protecting foundations with concrete or riprap reduces burrowing opportunities.

3. Eliminate harborage. Brush piles, stacked materials, and dense low vegetation near structures create shelter for tegus and other ground-dwelling invasive lizards. Keeping these areas clear reduces attractiveness.

4. Do not feed wildlife. Deliberate or incidental feeding of iguanas or other invasive lizards habituates them to human presence and concentrates populations near homes.

Reporting and Removal

Related Questions to Explore

• Are tegus dangerous to people? While not naturally aggressive, tegus are large and capable of severe bites and claw scratches when cornered. Keep a safe distance and report sightings to the FWC. For safe, immediate removal from your property, contact the trained handlers at Radix Pest Solutions.

• Can I legally remove an iguana or tegu from my property? Yes, Florida law allows homeowners to humanely remove them, but releasing captured invasive lizards is strictly illegal. Because trapping large, defensive reptiles carries a high injury risk, DIY removal is not recommended.

• Are green iguanas poisonous? No, green iguanas are not venomous, but they do carry Salmonella and can inflict painful tail-whips or bites. Handling them without proper precautions poses a direct disease and injury risk to humans and pets.

• Why do invasive lizards seem to be getting bigger? Their biological size ranges haven't changed, but as invasive populations mature in Florida, encounters with full-grown adults are skyrocketing. Seeing a massive four-foot tegu or monitor lizard in your yard is increasingly common.

• What is the FWC doing about invasive lizards? The FWC enforces bans, tracks sightings, and conducts research, but widespread landscape eradication is nearly impossible now. While the state focuses on macro-level management, protecting your specific property falls on you. Radix Pest Solutions bridges this gap with tailored property barriers, exclusion tactics, and active trapping.

Protecting Your Property From Invasive Wildlife

Invasive lizard management intersects with broader pest and wildlife management, particularly as tegu and iguana populations expand into new counties.

At Radix Pest Solutions, our technicians are familiar with the invasive species landscape in Florida and can advise on exclusion, harborage reduction, and when to engage licensed wildlife removal specialists.

Conclusion

The Florida Fish and Wildlife Conservation Commission maintains updated information on invasive species in Florida, including reporting tools and management resources.

If you have active iguana damage to your landscaping, potential tegu activity on your property, or broader pest and wildlife concerns, contact us for an inspection and assessment!