Florida is warm, wet, and has a long history of exotic-pet owners who got tired of the pet. The result is an ecosystem full of animals that evolved on other continents. Some are a nuisance. Some are rewriting the Everglades.
Burmese pythons
The big one, literally. Burmese pythons arrived through the pet trade; escaped and released animals established a breeding population in the Everglades, and nobody knows how many are out there now. What is known is what they eat. A 2012 study led by Michael Dorcas, published in the Proceedings of the National Academy of Sciences, compared roadside animal surveys in Everglades National Park from 2003 to 2011 with surveys from 1996 and 1997. Raccoon sightings were down 99.3 percent. Opossums were down 98.9 percent. Bobcats were down 87.5 percent. Rabbits and foxes were not seen at all.
The record python is a 19-foot, 125-pound female found in Big Cypress National Preserve near Ochopee on July 10, 2023, by 22-year-old python hunter Jake Waleri, verified by the Conservancy of Southwest Florida. The previous record was 18 feet 9 inches. The heaviest, also brought in through the Conservancy, weighed 215 pounds. The state and the South Florida Water Management District pay contracted hunters to remove them, and the two programs together passed 5,000 pythons removed. It is a drop in the bucket, and everyone involved says so.
Green iguanas
South Florida's iguanas are the ones that make the news every winter, when a cold front drops temperatures into the 40s and the lizards go torpid and fall out of trees. They are not dead, just stunned; they wake up when the sun comes out. Iguanas dig burrows that undermine seawalls and sidewalks, eat landscaping, and have become so established from Miami to the Keys that the state encourages homeowners to remove them.
Lionfish
The invader you can do something about. Lionfish are an Indo-Pacific reef fish, venomous-spined, with no natural predators in the Atlantic. They eat juvenile reef fish by the hundreds. Florida has no bag limit and no closed season on lionfish, and spearfishing them is actively encouraged. They are also excellent eating; the venom is in the spines, not the meat, and plenty of Keys restaurants will cook one you bring in.
The rest of the list
- Argentine black and white tegus: four-foot lizards that eat alligator and turtle eggs, established in Miami-Dade and spreading.
- Cane toads: toxic to dogs; a real hazard in suburban yards.
- Nile monitors: six-foot lizards living along the canals of Cape Coral.
- Veiled chameleons: released by breeders in the 1990s and 2000s, now living wild in parts of South Florida, where chameleon hunting at night with a flashlight has become its own hobby.
- Clown knifefish: a Southeast Asian predator established in the lakes of Palm Beach County.
- Rhesus macaques: a colony of monkeys along the Silver River near Ocala, descended from animals released for a jungle cruise attraction in the 1930s.
The rule: It is illegal to release a nonnative animal into the wild in Florida. FWC runs an Exotic Pet Amnesty Program that will take unwanted exotics, no questions asked.
Seeing it from the water
The Everglades is where the python story is written, and the boat tours out of Marco Island and Everglades City run the exact mangrove and river edges where the mammals used to be. You will see what is still there: wading birds, dolphins, manatees and gators. In the Keys, charter captains and dive operators run lionfish trips, and a Key West snorkel day is the easiest way to see a reef that is still holding on. Around Tampa Bay and Sarasota, the invaders are mostly on land; the water is the native Florida.
Questions people ask
What is the biggest python ever caught in Florida?
A 19-foot, 125-pound female Burmese python found in Big Cypress National Preserve on July 10, 2023, verified by the Conservancy of Southwest Florida. The previous record was 18 feet 9 inches.
How much damage have pythons done to the Everglades?
A 2012 study found raccoon sightings in Everglades National Park down 99.3 percent, opossums down 98.9 percent and bobcats down 87.5 percent compared with the 1990s. Rabbits and foxes were not seen at all.
Why do iguanas fall out of trees in Florida?
Cold. When temperatures drop into the 40s, green iguanas become torpid and lose their grip. They are not dead and recover when it warms up.
Can you eat lionfish?
Yes. The venom is in the spines, not the meat. Florida has no bag limit or closed season on lionfish and encourages removing them.
Is it illegal to release a pet into the wild in Florida?
Yes. FWC's Exotic Pet Amnesty Program accepts unwanted exotic animals so they do not end up in the ecosystem.