Burmese pythons are putting a squeeze on the Everglades.
By Amy Leinbach Marquis
There’s an invasive predator lurking in Everglades National Park, and it has an insatiable appetite for almost every wild thing we hold dear: birds, rodents, bobcats, deer—even the iconic American alligator. An exotic pet-gone-wild, the Burmese python may be responsible for altering Florida’s best places in big ways. And the National Park Service isn’t quite sure what to do about it.
The first offenders slithered quietly into the Everglades in the 1990s, and it’s no wonder why: Each year, Miami receives 12,000 shipments of wildlife to be sold as exotic pets, Burmese pythons among them. But some pet owners aren’t equipped to handle a python’s rapid growth spurt—20-inch babies can grow up to 12 feet and weigh almost 200 pounds by age two—so many people release the snakes into the wild.
Other snakes may have been freed in 1992 by Hurricane Andrew, which demolished a snake importer’s warehouse; the Everglades offer all the comforts of their Asian homes: a warm climate, thick vegetation for cover, trees for juveniles to climb, and waterways for quick travel. So they began spreading out into the mangroves, freshwater wetlands, and wooded uplands that make up the park’s 1.5 million acres. With few predators and a smorgasbord of prey, the Everglades quickly turned into a python’s paradise.
Then they started reproducing.
The park responded by setting up a python hotline, encouraging citizens to call in and report sightings. They also allow “authorized agents” to capture and deliver live pythons to park biologists. By euthanizing a snake and performing a necropsy, biologists can determine what they’re eating, and in turn, what kinds of park resources they’re affecting; they can also gauge general health and reproductive capability. By keeping them alive, researchers can test the effectiveness of traps, or even embed a transmitter and release them back into the wild, then track them from airplanes to get a sense of where they spend most of their time and how quickly they travel.
“We need to get as much information as we can about how well they’re doing and what kind of impact they’re having, so we can better understand if there are ways to control their numbers or mitigate their impacts,” says Skip snow, a wildlife biologist with Everglades National Park.
While there’s no set blueprint for how to eradicate the species, every little bit helps: In the last ten years, the park documented 1,300 Burmese pythons in and around the park that were captured, run over by cars and farm machinery, eaten by alligators, or suffered other fates. The unusually cold Florida winter killed a significant number of snakes as well, including nine of the 10 individuals that the park was tracking from airplanes.
But even if the park were to remove every wild, invasive python tomorrow, the future of the Everglades would still be threatened without systems in place to prevent such invasions from happening again. So the Florida Fish and Wildlife Conservation Commission created a program called Non-Native Amnesty Day, an event that gives overwhelmed pet owners a chance to turn in unwanted exotic pets to certified adopters better equipped to care for them. And last February, Sen. Bill Nelson (D-FL) proposed new legislation that would make it illegal to import nine species of constrictor snakes into the United States, or even transfer the animals across state lines; at the time this issue went to print, the comment period had been extended to mid-June.
“It’s not that we don’t like big snakes,” Snow says. “I wouldn’t be a wildlife biologist for the National Park Service if I didn’t appreciate the animals’ ability to make a living here. But large, exotic constrictors are not a piece of the Everglades National Park puzzle that we’re trying to preserve for the public. So we not only have to figure out how to address the problem now—we have to make sure it doesn’t happen again. And that’s what dealing with invasive plants and animals is all about.”
Prevention, after all, is much less costly than cleaning up a mess that’s already been made. Everglades National Park spends about $1 million annually on exotic-plant management, which includes efforts to eradicate Brazilian peppers, Australian pine trees, and the Old World Climbing Fern. To battle invasive wildlife species like Nile monitor lizards, Cuban tree frogs, sacred ibis, and numerous species of exotic python, the park needs hundreds of thousands of dollars more. “We’re clearly concerned about the Burmese python invasion,” says David Hallac, Everglades’ chief of biological resources, “but it’s really just a reminder of all the other exotic species we have. The problem is much bigger than the python alone.”
Some claim that Florida will never be able to fully eradicate its Burmese python population because nobody knows how. But that doesn’t mean we can’t learn from what we do know. “The take-home message here is that we don’t want this to happen again,” Hallac says. “When non-natives become established in a national park, we’re no longer able to interpret the native ecosystem. We need to learn from our mistakes.”