Just in case Florida didn’t have enough going against it already (looking at you Florida Man), the state that everybody loves to hate is currently being invaded. No, not by Cuba—by a variety of non-native plants and animals that are wreaking environmental havoc and causing billions of dollars in damage. These are six of the most destructive.
Giant African Land Snails
Giant African Land Snails, or G.A.L.S (technically, Lissachatina fulica) live up to their name. Native to Kenya and Tanzania, these monopods are obscenely huge and, the problem is, they’ve got sex drives and appetites to match.
GALS were initially imported to Florida in 1966 from Hawaii, and have since experienced a population explosion—thanks to their ability to digest over 500 species of local plants and their ability to lay upwards of 200 eggs a year (they’re also hermaphroditic). Adults can measure over a foot long and tip the scales at more than a pound, making them an enticing prize for exotic pet owners. But in the wild, they’re a dangerous pest, out-competing native species for resources and destroying property. GALS have developed a taste for calcium-rich stucco siding, which the snails use to produce their massive shells, and have been known to puncture car tires with their probosces in search of a meal.
Thanks to a concerted effort by the Florida Agricultural Commission—employing specially trained sniffer dogs, bait traps, and community involvement—the snail’s days appear numbered.
Monk Parakeet
Monk Parakeets, introduced to the US in the 1960s as pets, are unusual among the parrot family. Not only are they one of the few species to eat fruit, they are also the only species to build nests out of sticks rather than grasses. What’s more, these nests are communal, condo-like structures that can grow to the size of a small car. And the birds just love building them on top of power poles and electrical substations—where they cause regular power outages, fires, and cost millions a year in repairs.
But even with more than 100,000 individual birds in Florida alone, the Monk Parakeet is not often targeted as an invasive pest. Likely because it’s so much cuter and more charismatic than the other species on this list.
Green Iguanas
Despite the fact that they’re strictly vegetarian, or rather because of that fact, Green Iguanas are among Florida’s most destructive invasive species. While they don’t compete with native lizard species for food, as invasive Nile Monitors do, the iguana’s ravenous appetite can decimate lawns and gardens.
Per the Green Iguana Society:
Green Iguanas in Florida eat shrubs, trees, landscape plants, orchids, and fruits such as figs, mangos, berries and tomatoes. Ornamental vegetation can be decimated by one large iguana taking up residence in a yard. In addition to destroying landscaping efforts, iguanas also cause problems by digging nesting burrows that can undermine sidewalks, sea wells and foundations. Iguana feces are odiferous, unsightly, and may harbor Salmonella bacteria. Because iguanas often prefer to defecate in or around water, it is not uncommon for an iguana to use a private pool as a defecation area. Large adults may be aggressive towards people and pets if they feel threatened.
They also grow to over six feet long and come equipped with big burrowing claws, sharp teeth, and whip-like tails. Generally not something you want to tangle with while drunk.
Like the Monk Parakeet, mass eradication efforts of the Green Iguana are not common—some folks even welcome them as a new addition to the local ecosystem. However, the University of Florida recommends people help control the spread of the species by making their yards less iguana-friendly and treating them like the wild animals they are.
Cane Toads
Cane Toads aren’t just a threat to the local ecosystem—these large amphibians use their stout stature to out-compete, or outright eat, smaller native species. What’s more, the toads are far more toxic than native Southern and Oak Toads. They even pack a poison that can kill or seriously sicken pets.
In addition to building silt fencing to exclude the animals from yards and water features, the University of Florida recommends that if you find a toad longer than three inches in your yard, first positively identify it as a Cane Toad, then kill it dead using the following method:
Purchase a small tube of benzocaine ointment, which is used as a pain-killer for toothaches. There are several well-advertised brands as well as much less expensive store brands (generic brands). Simply take a strip of ointment about 1 inch long (more for very large frogs/toads) and spread it down the spine of the frog/toad from the neck to the tailbone. In 5-10 minutes the animal will be groggy; in 15-20 minutes it should be unconscious, and in about 30-40 minutes the frog/toad will die or be near death. Now put the frog/toad in a plastic container and place it in your freezer for 3 days. This is a humane way to kill amphibians because their bodies go into a state of torpor (metabolism slows way down) — just as they do in cold weather outside.
The freezer bit is to make sure the toad is good and dead, lest you accidentally bury the animal alive.
Burmese Pythons
Alligators used to be the apex predator of the Everglades. That is, until the Burmese Python came along. Introduced in the late 20th century after escaping from, or being released by, exotic pet owners, there are now an estimated 180,000 pythons loose in the Everglades. Their near omnivorous diet of smaller animals (everything from field mice to deer) and their large size—topping 18 feet and 200 pounds—make Burmese Pythons (and related exotic constrictors) one of the top threats to Florida’s ecosystem.
In response, the State of Florida has not only required annual licensing for exotic snake owners and made microchipping the snakes mandatory, but officials routinely hold Nonnative Amnesty Days where owners can give up snakes they can no longer care for rather than dumping them in the swamps.
And for the nearly 200,000 snakes already established in the Everglades, the Florida Fish and Wildlife Conservation Commission holds an annual month-long, state-sanctioned hunting competition, dubbed the “Python Challenge” in every January. Though, last year, the competitors only managed to net 68 snakes in total. Ironically, these snakes are endangered in their native Southeast Asian habitats because of over-hunting for their skins—which are made in to handbags, boots and such—and now they’re being hunted in the Everglades for the exact same reason. Image: Lori Oberhofer, National Park Service
Walking Catfish
We all know what happens when you give a mouse a cookie, but when you give a catfish the ability to survive out of water for days at a time, you’re just begging for trouble. Walking Catfish are native to Southeast Asia, Thailand specifically, and usually make their homes in stagnant pools and rice paddies. The ability to wriggle over dry land (so long as it stays moist) allows these fish to move to other, better feeding grounds when the current pool dries up.
These fish are voracious eaters, consuming smaller native fishes, crustaceans, and their eggs during times of plenty—and they’ll eat just about anything during lean times. They’ve even been recorded walking into aquaculture tanks and eating every living thing inside.
There is unfortunately not much that can be done to stop the Walking Catfish that hasn’t already been tried. The Federal government has already blacklisted all members of the family Clariidae as injurious wildlife, making them illegal to possess without a federal permit. And while their spread north has been halted by the freezing temperatures present outside of Florida, their ability to survive months without food in hypoxic water make the Walking Catfish a formidable foe.