EVERGLADES NATIONAL PARK, Fla. - Kristen Hart’s search for a cold-blooded killer came to an end at a perfect hideout - thick scrub brush, dense trees, and shade. She crouched with three scouts and whispered.
“Do you see her?’’ asked Hart, a research ecologist for the US Geological Survey. “Yeah, she’s in there,’’ answered Thomas Selby, a wildlife biologist. “I think she knows we’re here,’’ said Brian Smith, another biologist.
Within seconds, the 16 1/2-foot Burmese python uncoiled and tried to slither off. What happened next is a drama that plays out every week or so, as state and federal biologists try to prove — or disprove — that the giant invasive snakes are the reason for the near disappearance of rabbits, opossums, raccoons, foxes, and even bobcats in the southernmost section of the 1.5-million-acre Everglades.
Smith and Selby charged into the trees. “I’ve got the head!’’ Smith shouted. “Grab the tail!’’ They stumbled out with the writhing snake in a chokehold, huge mouth agape, ready to bite.
It was actually the second time biologists got their hands on Python 51 — the 51st caught. Two months ago, they surgically fitted her with a radio transmitter, motion detector, and global positioning system to study her diet and movements.
Now, the snake’s days of squeezing the life out of prey and giving birth to about four dozen babies every year are over. The scientists want to retrieve their equipment and the data it contains. She was euthanized, along with an even bigger snake, the largest ever captured in Florida, at 17 1/2 feet — more than twice as long as former basketball player Shaquille O’Neal is tall.
Burmese pythons are native to Southeast Asia. No one knows for certain how the snake entered the park. The theories that Hurricane Andrew blew them there from exotic pet shops and houses in 1992, or that numerous pet owners released them when they grew too large, are probably myths, according to Frank J. Mazzotti, a professor of wildlife ecology and conservation for the University of Florida.
“All it takes is three snakes,’’ he said, mating and laying an average of 50 eggs, and up to 100 eggs, per year.
Their population in the Everglades is estimated at anywhere between 5,000 and 100,000 by the US Geological Survey. The National Park Service says that more than 1,800 pythons have been removed from the park and surrounding areas since 2002.
Some game officials and citizens have suggested sending bounty hunters with guns and machetes into the park.
“Someone could tell you there are 10 pythons in this area, and you could walk all day and not see them,’’ Smith said.
Pythons prefer warmth, but many in the Everglades have managed to survive hard freezes, leading some biologists to worry about their ability to adapt and travel north. The snake has already been swimming and slithering toward the Florida Keys.
Once pythons are established, trouble seems to follow. A study coauthored by Hart, Mazzotti, and other researchers showed that when pythons started to appear in large numbers in the late 1990s and early 2000s, mammals in the southernmost part of the Everglades started to disappear.
For the study, researchers traveled nearly 40,000 miles over 11 years, observing wildlife in the southern area. They found that 99 percent of raccoons, 98 percent of opossums, and about 88 percent of bobcats were gone. Marsh and cottontail rabbits, as well as foxes, could not be found.
Nearly every news report blamed pythons, but the study did not conclude that. It said more research was needed.
Mazzotti is also examining the impact of humans, who have drained water for development.