Green iguanas are a large reptile population in Florida, primarily throughout the state’s southern half. Native to Central and South America, these lizards have established a strong presence in the subtropical Florida environment. Their bright green or sometimes orange coloration makes them a frequent sight in both natural areas and residential communities. Their proliferation has led to increasing public concern about their distribution and the consequences of their presence.
The Arrival and Adaptation of Green Iguanas
The establishment of green iguanas in Florida began with the pet trade, tracing back to initial reports in the Miami area in the early 1960s. Native to a large geographic area extending from Mexico down to Paraguay and Brazil, these reptiles were brought into the state as exotic pets. Feral populations grew primarily from two sources: iguanas that escaped captivity and those intentionally released by owners once the animals grew too large.
Florida’s climate is highly conducive to the iguanas’ survival and reproductive success, offering the mild winters and abundant vegetation necessary for them to thrive year-round. They are not cold-hardy, which historically limited their northern expansion, but the subtropical conditions of South Florida mimic their native tropical habitat. The iguanas reproduce frequently, with females laying clutches of 14 to 76 eggs. This, combined with a lack of natural predators in the urban environment, allowed their population to expand rapidly.
Current Geographic Range and Preferred Habitats
The core population of green iguanas is concentrated in South Florida, especially along the Atlantic coast where the climate is warmest. The densest concentrations are found in Miami-Dade, Broward, and Palm Beach counties, with established populations extending through Monroe and Martin counties. Their presence stretches along the Gulf Coast in areas like Collier and Lee counties, and they have been reported as far north as Hillsborough and St. Lucie counties.
These reptiles are highly adaptable, making use of both natural and human-modified environments. They are frequently found along the extensive network of man-made canals and levees in South Florida, which act as ideal dispersal corridors. Residential and urban landscapes offer optimal habitat, providing lush ornamental landscaping for food, and seawalls, docks, and culverts for basking and refuge. Iguanas are proficient swimmers and often bask on structures overhanging water, allowing them to quickly dive to escape threats. Females seek out specific environments for nesting, often digging burrows in sandy areas like golf course bunkers, construction sites, and canal banks to lay their eggs.
Ecological and Infrastructure Damage
The iguanas’ presence causes two distinct types of harm: damage to human infrastructure and negative impacts on native ecosystems. Structurally, their burrowing behavior is a significant problem, particularly around water management systems. They dig extensive tunnels, up to eight feet deep, into canal banks, levees, and seawalls, undermining the stability of these structures. This burrowing leads to erosion, which can compromise the integrity of sidewalks, foundations, and flood control infrastructure, requiring costly repairs.
Ecologically, iguanas are primarily herbivores with a voracious appetite for vegetation, damaging residential and commercial landscaping. They consume native plants, including species relied upon by indigenous wildlife, such as the nickerbean plant, a host plant for the endangered Miami Blue butterfly. Iguanas may also displace native species by occupying burrows belonging to the gopher tortoise and the Florida burrowing owl, both listed as threatened species. Furthermore, their droppings, often found on docks, pools, and lawns, can carry Salmonella bacteria, posing a public health concern.
Management and Removal Guidelines
Green iguanas are not native to Florida and are classified as an unprotected species, except by anti-cruelty laws. Property owners can remove them year-round without a permit. The Florida Fish and Wildlife Conservation Commission encourages residents to humanely remove iguanas from their private property. Relocating a captured iguana is illegal, and removal must adhere to humane methods to comply with existing laws.
For homeowners, non-lethal deterrence focuses on habitat modification and exclusion. This includes removing attractive food sources, such as fallen ripe fruit, and using fencing or netting to protect valuable plants and prevent access to basking areas. Simple harassment techniques, like spraying the animals with water or using reflective objects and intermittent noises, may also discourage them. If a large population is established or if a property owner cannot safely remove the animals, contacting a professional nuisance wildlife trapper is the recommended course of action. Professionals are equipped with the necessary permits and expertise to handle trapping, transport, and humane disposal.