Updated

WEST PALM BEACH, Fla. (AP) — It's been about two months since Florida issued a virtual open season on giant invasive Burmese pythons gobbling up rabbits, birds and even small alligators throughout the Everglades. Now there's another nonnative stealthy stalker that could soon be taking up residence in the region — Africa's largest snake, the rock python.

Three of these enormous constrictors that can grow to 20 feet and weigh 200 pounds have been found in the last few months in western Miami-Dade County, raising concerns that they could establish a breeding population, just like their Burmese cousins.

In South Florida's Everglades, where nonnative species of plants and animals are rampant, "it's business as usual" to find one invasive snake of any kind, said Scott Hardin, exotic species coordinator for the state Fish and Wildlife Conservation Commission.

"The thing that's a little concerning to us is the fact that we've had three sightings (of rock pythons) since the end of May, two in August," Hardin said. "We have to control this before things get out of hand."

The number of Burmese pythons in South Florida and throughout Everglades National Park has exploded in the past decade to potentially thousands, though wildlife officials aren't sure exactly how many are slithering around the region.

Scientists believe pet owners freed their snakes into the wild once they became too big to keep. They also think some Burmese pythons may have escaped in 1992 from pet shops battered by Hurricane Andrew and have been reproducing ever since.

In July, the state began issuing permits to volunteers willing to hunt them down. As of Sept. 21, 29 Burmese pythons had been captured and killed.

A key concern is that the growing number of pythons could upset the natural balance of the ecosystem as they feed on birds, small rodents and other native species.

While it's too soon to say whether the rock python may be next on the state's snake hit list, officials aren't taking any chances. They have enlisted experts, hunters and off-roaders to keep an eye out in the region for any more of these invaders. So far, six have been found in roughly the same area since 2002.

"I'm relatively optimistic that this isn't going to become an issue like we have with the other snake out there," Hardin said.

Hardin said he believes the rock pythons were released into the wild by pet owners or escaped, in the same way Burmese pythons began their march across the Everglades more than a decade ago.

Once a species like the python becomes established in a vast area like the Everglades, eradication is "close to nil," said Bob Reed, a snake ecologist with the U.S. Geological Survey.

There also is some concern that the African python, if it becomes established, could begin breeding with the Burmese snakes, creating a new population, he said.

While similar in size, the African rock python is known to be a bit more aggressive than the Burmese species. However, Reed noted, human encounters, given their small numbers found so far, would be rare, and if they are stumbled upon, either of the snake species are more likely to flee.

"That's a snake that is perfectly capable of killing someone if it wants to but not many people are going to be encountering those animals," he said, noting this is a state with more than a million alligators, several thousand crocodiles, panthers, bears and wild hogs, so the snakes should be the least of residents' concerns.

Added Eugene Bessette, a longtime snake breeder in the Gainesville area: "You stand a greater chance of getting attacked by a feral hog or feral cat than you do one of these snakes."