Python "Nightmare": New Giant Species Invading Florida

Christine Dell'Amore, National Geographic News 14 Sep 09;

Already squeezed by the invasion of the giant Burmese python, Florida now faces what one scientist calls one of the U.S. state's "worst nightmares."

Africa's largest snake—the ill-tempered, 20-foot-long (6.1-meter-long) African rock python—is colonizing the U.S. state, new discoveries suggest.

Six African rock pythons have been found in Florida since 2002. More troubling, a pregnant female and two hatchlings have been found, which means the aggressive reptiles have set up house.

More dangerous than even Burmese pythons—which are known to eat alligators (alligator-python picture)—the African pythons are "so mean, they come out of the egg striking," said Kenneth Krysko, senior herpetologist at the Florida Museum of Natural History in Gainesville.

"This is just one vicious animal."

So far the giant snakes have been found only in a single square mile (2.6 square kilometers) of suburban area west of Miami. Pet breeders unprepared for the pythons' ferocity may have released them, Krysko said.

What's "really scary" is that the new invaders only have to cross the road to enter Everglades National Park, where Burmese pythons have already eaten thousands of native animals, he said.

With the addition of the rock python, Florida is now an established home-away-from-home for three large alien constrictors—including the Burmese species and the boa constrictor—according to wildlife biologist Robert Reed, who studies invasive reptiles for the U.S. Geological Survey in Fort Collins, Colorado.

(The Florida python crisis will be covered in a future episode of Explorer on the U.S. National Geographic Channel. The National Geographic Channel is part-owned by the National Geographic Society, which owns National Geographic News.)

Pythons Threaten Mice and Men

In its native habitat, sub-Saharan Africa, the African rock python eats small mammals, antelope, warthog, herons, and other animals.

In Florida the African snake might "eat almost any warm-blooded animal that is big enough to ingest," as the Burmese python does, USGS's Reed said.

"Dozens of species of native wildlife, from white-tailed deer to 6-foot [183-centimeter] alligators to birds, have been found in the digestive tracts of Burmese pythons in Florida," said Reed, who is also working with the Florida museum's Krysko on the Florida python problem.

Also like the Burmese python, the African snake is a constrictor. Lacking poison, it kills animals by encircling and literally squeezing the life out of them.

Florida wildlife may not be the only creatures at risk. In Africa, rock pythons are known to have attacked humans, Krysko said.

Hidden in a Florida swamp, he added, the African python "could strike you and you wouldn't even know it was there."

Python + Python = Hybrid Supersnake?

African pythons have likely already made it into the Everglades, Krysko said. If so, it shouldn't be long before they encounter their Burmese cousins.

If the two python species mate, they may spawn a hybrid species, as has happened in captivity. And because of a biological phenomenon called hybrid vigor, there's an off chance the resulting snakes could be hardier, more powerful predators—assuming they're not sterile, as many hybrids are—USGS's Reed said.

"We can't rule out the possibility," Reed said, "that the introduction of genes from a different species might do something that would allow [the rock pythons] to be even more effective at persisting in Florida and perhaps expanding."

Worse Than the Burmese Python?

The rock python's expansion mirrors the Burmese snake's explosion for some Florida conservationists—and a chance to learn from past mistakes.

"The thing that scares me the most is that this could be another Burmese python," said Kristina Serbesoff-King, invasive species program manager for the nonprofit Nature Conservancy in Florida. (Read biologist Stuart Pimm's take on tackling the Florida python crisis.)

In a 1994 report the Florida Department of Environmental Protection sounded the alarm about the explosion of invasive species in the state, whose warmth and major international ports put it at particular risk.

The report specifically named the African rock python as a threat to pets, native wildlife, and small children. The advisory, however, predicted that in Florida the African snake would be unable to breed in the wild.

"Here we are, 15 years later, and that whole ounce-of-prevention story is so glaring," Serbesoff-King said.

"There's a real opportunity to [mount] an aggressive response" to get rid of the African rock python while the giant snake is still limited to a relatively small area, Serbesoff-King added.

One model, she said, may be the "python patrol" that the Nature Conservancy set up in the Florida Keys. After the Burmese python swam from the Everglades to the island chain and began munching rare Keys wildlife, the team started searching for and capturing the snakes to slow the species' spread.

The Florida museum's Krysko and USGS's Reed both agree that the African snake must be knocked out—and now.

The arrival of the Burmese python "was the biggest, [most] devastating problem that Florida ever could have imagined," Krysko said.

"Now we have a worse one."