By Jill Austin

A few pet Burmese pythons escaped or were released into Florida's Everglades more than 10 years ago — leading to an infestation of pythons both inside and outside Everglades National Park.

Now some of the pythons have swum more than 6 miles to the Florida Keys — worrying scientists that the invasive snakes will prey on the islands' native and rare species such as the Key Largo woodrat and the Lower Keys marsh rabbit.

So The Nature Conservancy is leading a Keys-wide "Python Patrol" task force in an early-detection, rapid-response effort to eradicate the invaders before they gain a permanent foothold.

“These snakes are incredible swimmers, and given that we have found six 7-foot snakes within a two-month period tells us this is not a pet-snake release issue,” said Alison Higgins, The Nature Conservancy’s Florida Keys land conservation program manager.  

In the Belly of a Python

The six pythons discovered in the Keys were killed by cars driving on a remote road in North Key Largo that runs between two conservation areas. “Who knows how many made it across?” Higgins says. 

But the first python was discovered alive in April 2007. Two researchers studying federally endangered Key Largo woodrats were checking on the status of a male woodrat wearing a radio transmitter that had moved more than a mile from its original documented habitat.

The signal led the University of St. Andrews graduate student and a volunteer assistant to a 7-1/2-foot Burmese python sunning itself. The contents of the captured snake’s stomach included not only the collared woodrat but another one as well. 

No Signs of Breeding…Yet

While pythons aren’t known to attack people, they are voracious and indiscriminate eaters.

To reach a full-grown length of about 13 feet, one python would need to eat nearly 200 pounds of food over five years. Some captured snakes have grown as large as 20 feet.

But the good news is that Conservancy biologists don’t believe the Keys pythons are yet breeding, since no smaller snakes have been found.

“These snakes have to be older before they disperse like this, so right now we have a good chance to prevent the next invasion," says Higgins. "We are empowering a lot of new partners in the community to help.” 

Snake in the Road!

Keys workers who spend much of their day driving (such as FedEx and U.S. Postal Service drivers) have been recruited to be part of an Eyes & Ears Team to call in sightings. Pythons often warm themselves on the roads, so the drivers are ideal candidates. 

“We had 57 attendees at our training — safety officers, meter readers, postal workers, road crews, landscape crews,” Higgins says. The training stressed safety and described to the volunteers python skin patterns. 

When Eyes & Ears Team members make a sighting and call the python hotline, the sheriff’s dispatch quickly contacts someone from the appropriate response team.

Everglades National Park biologist Skip Snow and Higgins are arranging to train responders in Everglades Park later this spring on safety, ethics, capture techniques, data collection and disposition.

 “We asked the volunteer to stay with the snake if they can until the first responder gets there, take a photo if possible, and provide data, such as time, date, size, etc.,” adds Higgins.

Next Stop: Virginia?

The Conservancy has been working for more than three years in Florida on the policy end of the invasive python issue — supporting a federal petition to get the Burmese python listed and taken out of the pet trade.

The Conservancy also supported Florida legislation that went into effect in January that requires new owners of Nile monitor lizards and five large constrictor snakes (including the Burmese python) to pay $100 for a permit and to install an identification chip so escaped pets can be tracked back to their owners.

But the snakes are potentially more than just Florida's problem. The native climate of the invasive pythons — from Pakistan to Indonesia — is the same as about one-third of the United States, according to new “climate maps” just released by the U.S. Geological Survey.

“It’s sad that it’s gotten this far — and unfortunately, there is no reason to think that they aren’t going to disperse farther north,” says Kris Serbesoff-King, The Nature Conservancy’s Florida invasive species program manager.

“Maybe they won’t get to New York City, but their native habitat compares to the entire southern United States,” adds Serbesoff-King. “The positive thing is that in the Keys there is a high likelihood that we can be successful.”

Jill Austin is a senior conservation writer with The Nature Conservancy in Florida. 

Nature photo credits (left to right): © Lori Oberhofer, National Park Service (Burmese python (Python molurus) and alligator locked in mortal combat); © Amber Plank (Burmese python); © Kris Serbesoff-King/TNC (Pet Amnesty, Miami)