Wildlife experts fear breeding pythons may be in Keys

The effort to keep invasive Burmese pythons out of the Florida Keys took a troubling turn in August.

Discovery of three young Burmese pythons near a North Key Largo subdivision within a three-week span likely means the snakes hatched on the island, wildlife experts said Thursday.

“This is a whole new wrinkle in managing the python situation,” Jeremy Dixon, manager of the Crocodile Lake National Wildlife Refuge on North Key Largo, said.

“Instead of dealing with pythons that swim over from the mainland, we could be dealing with a reproducing population here in Key Largo,” Dixon said. “Since these three were all 18 to 22 inches, it’s a pretty good bet they’re all from the same hatch.”

Two of the pythons were found a day apart, Aug. 2 and 3, in an oceanside canal near Valois Boulevard, about two miles north of the U.S. 1 one turn toward the mainland.

The third python was found Aug. 23 underneath a house near the Gulfstream Shores neighborhood, almost literally across County Road 905 from the Crocodile Lake refuge headquarters.

“They were all either in the water or near the water,” Dixon said.

Although can grow to more than 12 feet in length, Burmese pythons are not venomous and generally not a threat to people.

But pythons are suspected of having caused a sharp decline in wildlife, particularly small mammals, in Everglades National Park.

“Burmese pythons have been found to feed on a wide variety of mammals and birds in the Everglades,” says a park report. “By preying on native wildlife and competing with other native predators, pythons are seriously impacting the natural order of south Florida's ecological communities.”

That is a particular concern in the Keys, home to numerous endangered species. Much of undeveloped North Key Largo lies in state or federal ownership acquired to protect animals that need the tropical hardwood hammock to survive.

“We worry about pythons becoming established in the Keys because there are several at-risk populations of small mammals, like the Key Largo woodrat and the Key Largo cotton mouse, that would be easy prey for Burmese pythons,” said Bryan Falk, a biologist with the United States Geological Survey.

In the last five years, the Florida Fish and Wildlife Conservation Commission’s Exotic Species Hotline has logged 31 credible reports of Burmese pythons in the Keys. Most of the more recent sightings have been on Key Largo.

“To this point we’ve been dealing with [python] adults that we suspected were swimming over from the mainland,” Dixon said.

One python taken several months ago at the old Nike missile base inside the North Key Largo refuge had devoured an armadillo — a species far more common on the mainland than in the Keys. Last November, an adult female python of breeding age was captured at Ocean Reef, but no eggs were found.

“We have seen something of an uptick” in python numbers, Dixon said. “Our big concern is pythons are so secretive and able to conceal themselves, it’s difficult to know if they've been around.”

Keys residents can help by “keeping a lookout” for the Burmese pythons, especially if they travel on North Key Largo or Card Sound Road, he said. If a python is seen, call the state’s Exotic Species Reporting Hotline: 888-Ive-Got1 (888-483-4681), or go online at IveGot1.org. A mobile app for smartphones is available.

Upcoming projects targeting the pythons on North Key Largo include deploying “artificial refugia,” or sites that may be attractive to pythons. That could lead to easier capture.

A proposal to try a new version of a python-sniffing dog is under consideration by state and federal wildlife agencies.

This story was originally published September 22, 2016 at 1:45 PM with the headline "Wildlife experts fear breeding pythons may be in Keys."