Burmese pythons prosper in Everglades, though chilly winter reduced their number

By Paul Scicchitano
Tuesday, May 18, 2010

Maybe it was Hurricane Andrew blowing down a snake importer's warehouse in 1992. Maybe it was snake lovers who bought cute baby reptiles, only to dump them in the wild when they grew too voracious.

Florida wildlife officials say they may never know their origin, but there is no doubt about this fact: Florida is home to thousands of Burmese pythons that have turned the Everglades into a nesting area, raising concerns about their impact on native wildlife and possible migration into developed areas.

"People already have this built-in fear of snakes," said Ron Magill of Miami Metrozoo. "Now you're talking about 20-foot snakes . . . ."

Yet in recent months, entire clusters of these great serpents of Southeast Asia -- which can grow up to weigh more than 200 pounds -- have been turning up dead in what would typically be their mating season, one of the few welcome casualties of the record cold temperatures that beset the Sunshine State in early 2010.

"Our scientists believe that 50 percent of the population of Burmese pythons was decimated with the recent cold snap," declares Pat Behnke, chief spokeswoman for the Florida Fish and Wildlife Conservation Commission, with evident relief.

Dotted with giraffelike spots, the pythons have been living among the indigenous alligators, crocodiles and panthers that have laid claim to being the largest and fiercest predators in the 1.5 million-acre expanse of Everglades National Park and surrounding areas. As with other invasive species -- from the africanized honeybee to the Potomac-loving snakehead fish -- that challenge an ecosystem, the Burmese python poses a threat to its fragile new home.

No one knows how many Burmese pythons inhabit South Florida; estimates range from a few thousand up to as many as 150,000. Both federal and state officials caution that the true number is probably substantially lower than the worst extreme. Still, many Floridians see the creature, with hinged jaws that can open wide enough to accommodate a human, as a scourge that can make the snake thriller "Anaconda" seem almost like a documentary.

Even with this winter's deadly cold temperatures, thousands of pythons are believed to be roaming the woods, swamps and levees of South Florida. They prey on raccoons, rabbits, bobcats, house wrens, and white ibises. They also pose a potential threat to protected species such as the American alligator and the Key Largo wood rat. Indeed, a 2003 National Park Service photograph shows the outcome of a death match between a large python and an alligator: the dead gator protruding from the snake's carcass.

The coldest winter since the early 1980s hit South Florida this year, according to the National Weather Service. (Miami had its second-coldest winter in history.) Burmese pythons, creatures of tropical climates in Southeast Asia, are particularly susceptible to the cold, preferring temperatures in the mid-80s except when breeding.

As a result, "we are not finding them alive in great numbers. And the ones that we are finding alive are not in good shape," says Behnke, adding that officials now have some degree of comfort that the snakes are unlikely to migrate north.

Nonetheless, state and federal officials have rolled out a myriad of measures to stop or at least slow the python's possible migration, ranging from special radio transmitters implanted in some adult snakes, to a python hotline, unmanned aerial vehicles and, in the future, possible thermal imagery.

Officials recently sanctioned the first special hunting season on state-owned land for "reptiles of concern," though not a single python kill was reported by the time the hunt ended April 17. Pythons, it turns out, are good at blending into the environment. Animal experts say hunters might not be able to spot a python even when they are standing right beside one in the wilderness.

Since 2000, 1,496 Burmese pythons have been "removed" -- i.e, destroyed or captured for field research -- in and around Everglades National Park, including 367 last year and 162 through May 9 of this year.

Linda Friar, a spokeswoman for the park, did not have an estimate for how many pythons may have perished there because of the cold, but she said that nine of 10 "Judas snakes" -- implanted with radio transmitters that allow trackers to follow them to other snakes -- succumbed to the weather. (Burmese pythons tend to live in groups.)

Scientists hope to obtain information from the snakes they track to develop effective control programs. Those efforts may or may not include a greater role for hunters. "There's going to be some American ingenuity in how that is done," explains longtime Florida snake hunter "Captain" Dave Markett. "There's not a university that you can go to and get a degree in capturing Burmese pythons in the Florida Everglades."

Most sightings and captures of pythons occur in developed areas of the region, such as near roads and canal levees. The encounters can be disconcerting.

At the Krome detention center, located in a part of Miami near the Everglades, an off-duty security guard recently came face to face with a 13-foot python as he left work. "This monster was crossing the street," said the guard, who did not want his named used because he wasn't authorized to talk to a reporter. He added that he would have been more frightened had he not been watching from the safety of his van. "I had to wait and let this thing cross."

Scicchitano is a freelance writer based in Miami.

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