Burmese Pythons, Other Invasive Animals, Devour the Competition in Florida
“[Pythons] can take out one of our apex predators, which are alligators and crocodiles, and then it'll take down some of the other native animals that are small mammals — some of the rats, the mice, the marsh bunnies — things that are supposed to be food for other things,” says Mike Hileman, park director of Gatorland, a theme park and wildlife preserve in Orlando. “So, they compete with our native animals, and because they're a more dominant species, they win that battle.”
The Everglades is among the world’s most unique and delicate ecosystems. The python invasion is upsetting the fragile balance of the 6 million-square-kilometer wetlands preserve, which is home to rare and endangered species like manatees, the Florida panther and the American crocodile.
“Once a species starts reproducing in the wild, and they have a system that works for them, it's almost next to impossible to eradicate them,” Hileman says.
Florida is grappling with the most severe invasive animal crisis in the continental United States. The invasives flourish in the state’s subtropical climate, characterized by hot, humid summers and wet, mild winters. There are more than 500 non-native plant and wildlife species in the state, some of which — like pythons — are taking over the habitat and threatening the environment.
“They form almost like a monoculture of the invasives, and when your biodiversity plummets, then the environment isn't as able to withstand perturbations like climate change,” says Kurt Foote, a ranger with the National Park Service and natural resource management specialist at Fort Matanzas National Monument in St. Augustine. “Nature relies on variety, and when you don't have variety, it's just more susceptible to collapse.”
There is a flourishing reptile pet trade in Florida. In 1992, Hurricane Andrew destroyed a Burmese python breeding facility, releasing the animals into the wild. The Category 5 hurricane also leveled thousands of homes, setting numerous exotic pets free.
However, the very first Burmese python was found in the Everglades in 1979, more than a decade before Hurricane Andrew, and was probably a pet that escaped or was intentionally released by its owner. Florida residents are no longer allowed to keep Burmese pythons as pets.
“Animals can be a lot of work. The parrots are loud; they live almost 80 years. Tortoises can get really big and live 100 years. So, it's a big commitment to have a lot of these animals,” says Kylie Reynolds, deputy director of Amazing Animals Inc., a nonprofit exotic animal preserve in St. Cloud that takes in non-native animals that were once people’s pets.
“People sometimes just go, ‘You know, it's nice in Florida. We'll just let it loose.’... Maybe they think their animal would be happier free. But again, they could compete for our natural resources with our native wildlife,” Reynolds says.
In addition to Burmese pythons, Florida’s most problematic invasive animals include lionfish, feral hogs, Argentine black and white tegu lizards, and Cuban tree frogs, which can be found in many parts of the state, including Fort Matanzas.
“They're a bigger tree frog than what we have here by quite a bit, and they're also fairly omnivorous, and they will eat the native tree frogs,” Foote says. “Like a lot of invasives, when they get here, they don't have the things that predated them or competed with them in their homelands. They get here and without that pressure, they're able to really breed and reproduce.”
Feral hogs, originally brought to Florida by Spanish explorers in the 1500s, cause millions of dollars' worth of damage to crops each year. The animals, which are found statewide, disrupt the soil in areas such as Lake Apopka in Mount Dora that biologists are trying to restore.
“We're planting native vegetation. … A lot of times, they're rare or endemic species,” says Ben Gugliotti, land manager of Lake Apopka North Shore, a nature preserve. “The hogs will come in and root up those areas, basically destroying the planting areas that we're trying to restore. And then also actually create a secondary opening for invasive plant species that move into those disturbed soil areas.”
Argentine black and white tegu lizards are on the mind of Cheryl Millett, manager of The Nature Conservancy’s Tiger Creek preserve in Babson Park, which sits on Florida’s oldest and highest land mass.
“It's a biodiversity hotspot. And yeah, we have a lot of things that … don't exist anywhere else,” Millett says. “And if we lost them here, we wouldn't have them anymore on Earth.”
She’s most concerned about tegu lizards, which haven’t reached Tiger Creek yet but have been spotted nearby. They can grow up to 1.5 meters long.
“They found baby gopher tortoises in the guts of tegu lizards that have been found in South Florida,” Millett says. “They can eat baby gopher tortoises. I'm really worried about their potential impact here.”
Gopher tortoises are listed as federally endangered. They are a keystone species, which means they are critical to the surrounding ecosystem because they provide shelter for hundreds of other animals.
“[Tegu lizards] love gopher tortoise burrows, and they've been found using gopher tortoise burrows in South Florida,” Millett says. “Gopher tortoises create these burrows. They're like 10 feet deep, and can be 30 feet long, and they harbor over 300 different species in them.”
Florida spends more than $500 million a year trying to contain invasive species and the damage they cause. Officials organize hunts, exotic pet amnesty programs, and utilize other methods to combat invasive species. But it might come down to educating the future.
“Our generation, we already have preconceived ideas. We're lost. We're not going to change anything,” says Hileman of Gatorland, who speaks to school groups about wildlife conservation. “We’ve got to get with the little guys, and we got to get them on the same team so they can spread that message to their kids as they get older.”