'Judas Snakes' help researchers remove pythons from the Everglades

June 1, 2006

GAINESVILLE, Fla. — Removing gigantic pythons from a place they’re not wanted is no easy feat, but University of Florida researchers have found a high-tech way to make it easier – they’re sending radio-tracked pythons out into Everglades National Park to do the work for them.

Frank Mazzotti, an associate professor with UF’s Institute of Food and Agricultural Sciences, leads a team using ‘Judas snakes’ to lure – and catch – other Burmese pythons from the park, where they’re not welcome.

Pythons, which can grow longer than 20 feet and weigh more than 200 pounds, are released in the park by pet owners who don’t want or can’t handle them anymore. They’ve been causing problems in the park since the mid 1990s – their battles with native alligators the most widely documented.

Mazzotti credits National Park Service officials for having the courage to go ahead with the snake-tracking project, despite its risk.

“It would’ve been easier for them not to do this. We’re deliberately releasing a non-native species into a national park,” said Mazzotti, based at UF’s Fort Lauderdale Research and Education Center.

But while a python has the strength to overpower a human, Mazzotti says he believes they pose a far bigger risk to people who hit the snakes with their cars or crash trying to avoid one.

“Python attacks are not impossible, but I’d say that someone driving a Honda Civic who hits a 14-foot, 100-pound python is more likely to have a serious problem,” he said.

Mazzotti is presenting the group’s findings next week at an Everglades restoration conference in Lake Buena Vista.

Last winter, researchers caught four snakes, implanted pinkie-sized radio transmitters in them, tagged them and turned them loose in the park. Then for three months, the scientists kept tabs on the snakes’ whereabouts, using them to find other pythons.

Three of the four original snitch snakes helped researchers find 15 more untagged snakes – 12 of which were caught and euthanized. The fourth Judas snake had trouble with stitches from the implanted transmitters and was removed from the study.

The Burmese python, native to Burma in Southeast Asia, is one of the world’s largest snake species. One of the snakes found in the Everglades was 16 feet long and 152 pounds.

Everglades wildlife biologist Skip Snow said the behemoth snakes must be removed because they disrupt the park’s natural order. They’ll eat anything from gray squirrels to bobcats, he said, and they’re a direct threat to park officials’ attempts to restore some native species – such as wading birds and round-tailed muskrats – to the park.

“We don’t want them here. They came from the pet industry and are a direct result of the pet industry. They didn’t sneak in here, didn’t come in on the wind or hitchhike here. They were brought here and as a result, are breeding in the wild,” Snow said.

Park officials have either caught or found the remains of more than 212 pythons, 95 of them in 2005.

Mazzotti said the idea to radio-track the giant snakes came from a workshop in South Florida in July 2005 on invasive reptiles. The experts gathered there recommended the method because it had been used successfully to track the brown tree snake, an invasive species that wreaked havoc on native animals in Guam.

The team, which began the tracking just five months later, included Mazzotti, other UF staff and students and biologists from the U.S. National Park Service, the U.S. Geological Survey and North Carolina’s Davidson College.

Researchers began the Florida project wanting to answer three questions: Do pythons move away from the more manmade areas where they were usually seen, such as roads and berms, in favor of the park’s more natural habitat? If released, would the pythons lead researchers to other pythons or stay on their own? And most important, after the snakes were released, could they be recaptured?

During the December 2005 to March 2006 experiment – believed to be the pythons’ breeding season – researchers learned that the snakes had moved anywhere from hundreds of meters to more than a kilometer from where they’d been caught, often making homes in elevated forest areas. They learned that the snakes do find each other in the wild. And they learned they could indeed recapture the snakes, using transmitters’ beeps to zero in on their location.

They hope now to get funding for more research, focusing on questions such as how much of the national park and adjacent lands the pythons are using, and whether the snakes are social enough to find each other apart from their breeding season.

Burmese pythons, which can live up to 25 years, are nonvenomous constrictors but can overpower a human. Pythons suffocate their prey before swallowing it.

Though they prefer rodents, birds or rabbits, they’ll eat just about any live animal. They are good swimmers, move well on the ground and are strong tree-climbers, undoubtedly making the marshy Everglades seem to them an ideal fit.