Florida is home to roughly 60 lizard species, and their diets span a wide range from tiny flying insects to bird eggs, fruit, and even other lizards. What any particular lizard eats depends heavily on whether it is one of the state’s native species (most of which are insect-eaters) or one of the many introduced species that now thrive in Florida’s subtropical climate. Just as varied are the things that can actually harm lizards when eaten, from toxic native grasshoppers to pesticide-laced prey to well-meaning handouts of human food.
What Native Florida Lizards Eat
Most of Florida’s native lizards are small-bodied insectivores. The green anole, the state’s only native anole, feeds almost entirely on small arthropods: flies, beetles, moths, spiders, crickets, and ants. Fence lizards and skinks share a similar menu, snapping up whatever invertebrates they encounter on tree bark, leaf litter, and garden walls. These species are opportunistic, meaning they rarely specialize in one prey type but instead eat whatever appropriately sized bug crosses their path.
A few native species are slightly more adventurous. Florida’s glass lizards, which are legless and often mistaken for snakes, eat insects but also take small snails and occasionally other small lizards. Broadhead skinks, the largest skink in the Southeast, will eat smaller lizards and sometimes berries. But by and large, if you are watching a native Florida lizard hunt, it is hunting bugs.
The Diets of Florida’s Invasive Lizards
Florida has become a hotspot for non-native lizard species, many of which eat far more varied diets than the natives. The most prominent of these are Argentine black and white tegus, Nile monitors, green iguanas, brown anoles, knight anoles, and several species of curly-tailed lizards and agamas. Their eating habits are a major reason wildlife managers pay close attention to these animals.
Argentine black and white tegus are true generalist omnivores. Stomach-content analyses of tegus removed from central Florida documented close to 100 unique prey items from about 40 identifiable species. Their diet includes invertebrates like insects, crustaceans, spiders, and snails; vertebrates including fish, frogs, lizards, snakes, turtles, birds, and mammals; and a range of plant material, mainly fruit.1Southeastern Naturalist. Diet of the Invasive Argentine Black and White Tegu in Central Florida Vertebrate prey showed up in stomach contents at a strikingly high rate compared to tegu populations elsewhere. In central Florida, about four out of five tegus examined had consumed vertebrate prey, compared to roughly a third in southern Florida and an even smaller fraction in their native range in South America.2BioOne Complete. Diet of the Invasive Argentine Black and White Tegu in Central Florida That includes hatchlings of the gopher tortoise, a state-listed threatened species, which makes the tegu’s appetite a direct conservation concern.
Nile monitors, another large invasive reptile established in parts of Palm Beach and Broward counties, are similarly broad feeders. Researchers who examined the gut contents of removed Nile monitors found gastropods, millipedes, crustaceans, spiders, insects, fish, amphibians, reptiles, reptile eggs, birds, and mammals. Adults had the widest dietary diversity, and there was no meaningful difference in what males and females ate. Because Nile monitors are active foragers with such a broad diet, food availability is unlikely to limit where they can spread in Florida.3Journal of Herpetology. Diet of Nile Monitors (Varanus niloticus) Removed from Palm Beach and Broward Counties, Florida, USA
Green iguanas, perhaps the most visible invasive lizard in South Florida, are primarily herbivores. They eat flowers, leaves, and fruit from a wide variety of ornamental and native plants, including hibiscus, bougainvillea, and nickerbean. They occasionally eat insects or snails, but vegetation makes up the vast majority of their diet. Brown anoles, the small lizards you see on nearly every south Florida sidewalk, are insectivores much like native green anoles but compete with them aggressively for the same food resources.
How Urban Environments Shape What Lizards Eat
Florida’s cities and suburbs have created a buffet of new opportunities for lizards, particularly invasive ones. Urban habitats concentrate certain types of prey and introduce entirely new food sources that would not exist in a natural setting. Dumpsters, for example, appear to play a surprisingly specific role for at least one invasive species.
Researchers studying the African rock agama in urban southern Florida noticed that the lizards congregated in unusually high numbers around commercial dumpsters. The hypothesis is that dumpsters offer a combination of benefits: refuge from predators, surfaces useful for thermoregulation, and concentrated arthropod prey attracted to the refuse. Because dumpsters and similar human structures like electrical units and building crevices are largely ignored by native species, the agamas face little competition for these resources.4Biological Invasions. Dumpsters and other anthropogenic structures as habitat for invasive African rock agama lizards in Florida The pattern illustrates how human infrastructure can essentially create ecological niches that invasive species fill more readily than natives.
Outdoor lighting is another urban feature that indirectly shapes lizard diets. Porch lights and streetlights attract flying insects at night, and several lizard species, including brown anoles and Mediterranean geckos, have adapted to forage near these light sources. It is a common sight in Florida to see geckos perched near a porch light at dusk, picking off moths and beetles one by one. This feeding strategy barely exists in natural habitats and is almost entirely a product of the built environment.
Seasonal Shifts in Diet
Florida’s climate is subtropical rather than truly tropical, and even in the warmest parts of the state, food availability shifts through the year. For tegus, this has measurable dietary consequences. Vertebrate prey shows up most frequently in spring stomach contents, while invertebrates and plant material dominate in summer.2BioOne Complete. Diet of the Invasive Argentine Black and White Tegu in Central Florida The spring peak in vertebrate consumption lines up with the nesting season of many ground-nesting species, including the gopher tortoise, making that window an especially critical period for species already under pressure.
Smaller insectivorous lizards experience seasonal dietary changes too, though the shifts tend to be less dramatic. In winter, cooler temperatures reduce insect activity, and cold snaps can temporarily suppress both lizard metabolism and prey availability simultaneously. Most native lizards slow down considerably during Florida’s mild winters, eating less and basking more. Invasive species from tropical origins, like green iguanas, can be caught off guard by unexpected cold fronts, sometimes falling out of trees in a torpid state when temperatures dip into the low 40s Fahrenheit.
Prey That Can Harm or Kill Lizards
Not everything a lizard encounters on a Florida lawn is safe to eat. A few common species are genuinely dangerous prey items, and the most notorious is probably the eastern lubber grasshopper. These large, brightly colored grasshoppers are abundant across Florida from late spring through fall, and their warning coloration is well-earned. Lubbers produce an internal toxin that is synthesized by the insect itself rather than sequestered from plants. Even first-stage nymphs raised entirely on lettuce carry the compound. A single small lubber can induce vomiting in a lizard or bird that has never encountered one before, and experienced predators quickly learn to avoid them.5Oxford Academic (Journal of Integrated Pest Management). Biology and management of Romalea eques (Orthoptera: Acrididae) The toxin is most harmful to lizards and birds, somewhat less so to amphibians and mammals, and only mildly problematic for invertebrate predators.
Fire ants, another invasive species abundant throughout Florida, also pose risks. Their venom can injure or kill small lizards, particularly hatchlings, and fire ant mounds sometimes threaten lizard eggs directly. At the same time, some lizard populations appear to have adapted to eating fire ants without suffering the effects that would harm a naïve individual. The relationship is complex and still being studied, but the general advice for anyone keeping or rehabilitating a Florida lizard is straightforward: avoid feeding them fire ants or lubber grasshoppers.
Pesticide Contamination and Chemical Risks
Florida’s warm climate means year-round pest control, and that means lizards regularly encounter prey insects that have been exposed to pesticides. This is a serious and underappreciated risk. Research on the insecticide fipronil, which is widely used in ant baits, termite treatments, and agricultural applications, found that it is far more toxic to lizards than was previously recognized. When lizards were fed prey contaminated with fipronil at a single dose, roughly two-thirds of them were dead or severely debilitated within four weeks. Even lizards that received the chemical through a less natural route of exposure still had mortality above 40%. Survivors showed reduced feeding, weight loss, and organ shrinkage.6Environmental Toxicology and Chemistry. Toxicity and pathogenicity of Metarhizium anisopliae var. acridum (Deuteromycotina, Hyphomycetes) and fipronil to the fringe‐toed lizard Acanthodactylus dumerili (Squamata: Lacertidae)
The practical takeaway is that if you enjoy having lizards around your Florida yard, broadcast use of systemic insecticides is one of the fastest ways to harm them. Lizards eat contaminated insects and absorb the chemicals secondhand. Fipronil is just one compound, but it is an instructive case because its extreme toxicity to lizards was not even known before the study tested it directly. Many homeowners who apply granular ant baits or termite treatments have no idea they are creating a toxic food chain in their own backyard. If you want to keep lizard populations healthy, targeted and minimal pesticide use matters far more than anything you might deliberately feed them.
What Not to Feed Lizards
Whether you are caring for a pet lizard, rehabilitating a wild one, or just thinking about leaving food out for the anoles on your patio, several categories of food should be avoided.
- Human food: Bread, rice, processed snacks, and cooked meat are all inappropriate for any Florida lizard. Research on reptiles that shift toward diets dominated by a narrow range of human-associated food sources shows that these animals develop elevated lipids and an overall nutritional profile resembling a fast-food diet, with poor representation of the full range of nutrients they need.7Oxford Academic. The fast-food effect: costs of being a generalist in a human-dominated landscape Sedentary animals with limited home ranges are especially vulnerable to accumulating excess cholesterol and triglycerides on such diets.
- Wild-caught insects from treated areas: As discussed above, insects from areas treated with fipronil or similar systemic insecticides can be lethal. If you feed insects to a pet or rescued lizard, use captive-bred feeder insects from a reputable source rather than catching bugs from a sprayed lawn.
- Lubber grasshoppers: Their synthesized toxin is specifically dangerous to lizards. Even experienced lizard owners sometimes do not realize that a big, slow, easy-to-catch grasshopper is actually one of the most dangerous prey items in the Florida yard.
- Lightning bugs (fireflies): Fireflies contain compounds called lucibufagins that are cardiotoxic to many reptiles, including lizards. Even a single firefly can kill a small lizard like a bearded dragon or anole. This is well established in herpetoculture and is one of the most commonly cited fatal feeding mistakes.
- Fruit and vegetables for insectivores: Green anoles, brown anoles, fence lizards, and geckos are insectivores. Offering them fruit, lettuce, or vegetables provides no meaningful nutrition and can cause digestive issues. The exception is herbivorous species like green iguanas, which do eat plant material, but even they need a carefully balanced selection rather than whatever produce you have on hand.
Calcium and Nutritional Deficiencies
For anyone keeping a Florida lizard in captivity, nutritional metabolic bone disease is one of the most common and preventable health problems. It develops when lizards do not get enough calcium, vitamin D3, or vitamin A, and it leads to softened bones, deformities, tremors, and eventually death if untreated. Research on captive chameleons demonstrated that animals receiving no dietary supplementation of calcium, vitamin A, and cholecalciferol developed the disease, while those with proper supplementation did not.8The Journal of Nutrition. Nutritional Metabolic Bone Disease in Juvenile Veiled Chameleons (Chamaeleo calyptratus) and Its Prevention The condition is described as one of the most frequently observed problems in reptile keeping.
In the wild, lizards get calcium from the exoskeletons of insects and from incidental exposure to UVB sunlight, which allows them to synthesize vitamin D3. In captivity, both of these sources are limited. Feeder crickets and mealworms are relatively low in calcium on their own, which is why reptile keepers dust insects with calcium powder before offering them. A UVB lamp is also critical for indoor enclosures. Without it, even a calcium-supplemented diet may not prevent bone disease, because the lizard cannot metabolize the calcium properly without adequate vitamin D3.
This issue is worth understanding even if you do not keep lizards as pets. Well-meaning people who find injured anoles or geckos sometimes attempt to rehabilitate them at home. Feeding a recovering lizard crickets from the pet store without dusting them, or housing the lizard in a box without UVB lighting, can cause metabolic bone disease surprisingly quickly in small species. If you find an injured lizard and want to help, a licensed wildlife rehabilitator with reptile experience is a far better option than a DIY setup.
Parasites Lizards Pick Up Through Food
What lizards eat also determines what parasites they carry, and this has become a growing concern in Florida as invasive parasites spread through the food chain. One parasite under active study is Raillietiella orientalis, an invasive pentastome (a worm-like parasite that lives in snake lungs as an adult) that is spreading rapidly through Florida. Researchers found that brown anoles and insects both became readily infected after consuming food contaminated with the parasite’s eggs. The life cycle appears to require a chain of three hosts: the eggs hatch in insects that eat contaminated feces, the insects are eaten by lizards or frogs, and those intermediate hosts are then consumed by snakes, where the parasite matures.9Journal of Herpetology. Infection Experiments Indicate That Common Florida Anurans and Lizards May Serve as Intermediate Hosts for the Invasive Pentastome Parasite, Raillietiella orientalis
For the average person watching lizards in their yard, this is not a direct health threat. Pentastome parasites of reptiles do not typically infect humans. But the finding is a good illustration of how interconnected lizard diets are with the broader ecosystem. The bugs a lizard eats carry organisms that pass through the lizard and into whatever eats the lizard next. In a state where invasive species are constantly reshuffling these food webs, those chains of transmission are becoming more complicated and harder to predict.
What Tegus and Monitors Mean for Native Wildlife
The diet breadth of Florida’s largest invasive lizards has real consequences for species that were never exposed to these predators before. Tegus in central Florida eat gopher tortoise hatchlings, which emerge from underground nests and are small enough for a tegu to swallow. Gopher tortoises are a keystone species in Florida’s sandhill and scrub habitats, and their burrows provide shelter for hundreds of other species. Losing hatchlings to a novel predator that did not exist in the ecosystem a few decades ago adds pressure to a species already dealing with habitat loss.
Nile monitors, with their even broader diet, pose similar risks. Their consumption of bird eggs and nestlings threatens ground-nesting and low-nesting bird species, and their appetite for reptile eggs puts native lizard and turtle populations at additional risk.3Journal of Herpetology. Diet of Nile Monitors (Varanus niloticus) Removed from Palm Beach and Broward Counties, Florida, USA Because both tegus and monitors are active foragers rather than ambush predators, they cover ground and encounter nests that might otherwise go undiscovered by native predators.
Florida’s wildlife management agencies run active removal programs for both species, and understanding their diets is central to setting priorities. The seasonal spike in tegu vertebrate consumption during spring, for example, has informed the timing of targeted trapping efforts. If you encounter a tegu or Nile monitor in the wild, the Florida Fish and Wildlife Conservation Commission asks that you report the sighting. Neither species should be fed or encouraged to stay in residential areas, no matter how interesting they are to watch.
Feeding Wild Lizards in Your Yard
Plenty of Florida residents enjoy the lizards on their property and wonder whether they should put out food for them. For small native insectivores like green anoles and southeastern five-lined skinks, the honest answer is that you help them more by managing your yard in ways that support natural insect populations than by offering supplemental food. Reducing pesticide use, keeping leaf litter in garden beds, planting native flowering plants that attract pollinators and other insects, and leaving a shallow dish of water in a shaded spot all create conditions where lizards can feed themselves on a nutritionally complete diet of wild prey.
Deliberately feeding wild lizards, especially invasive ones, tends to create problems. Green iguanas that associate humans with food become bolder around houses and do more damage to landscaping and infrastructure. Tegus that learn to visit a property for handouts are harder to trap and remove. Even feeding native species can backfire: concentrated food sources attract more animals to one spot, increasing competition and disease transmission. The best thing you can do for Florida’s lizards is give them habitat, not a meal.