Efforts to control invasive Burmese pythons in Florida may get some help from the largest tracking study ever conducted on the snakes — in either Florida or their native Southern and Southeast Asian habitat.
A study headed by the U.S. Geological Survey in Everglades National Park has identified the typical size of the home range for the invasive snake, which can grow to almost 20 feet in length.
It also found evidence that multiple snakes often share common areas.
"These high-use areas may be optimal locations for control efforts and further studies on the snakes' potential impacts on native wildlife," said the study's lead author Kristen Hart, a USGS research ecologist. "Understanding habitat-use patterns of invasive species can aid resource managers in designing appropriately timed and scaled management strategies to help control their spread."
Researchers caught 19 pythons in the wild, placed radio and GPS tags on them and released them again. The study tracked the snakes for 5,119 days.
The tracking data revealed that a python's average home range is an area of about nine square miles, with a preference for sloughs and coastal locales within the Everglades.
"It has to do with food and sex," said Hart, describing the study's findings of where the snakes go to eat, mate and find shelter from inhospitable weather. Common-use areas tend to be tree islands within the wetland park.
Burmese pythons are large-bodied constricting snakes — one of the five largest species of snake in the world. They live as long as 25 years.
Their presence in Florida has led to an alarming decline in some species of native small mammals and birds, a staple of the python diet.
Some experts think the python invasion may have begun in 1992, when Hurricane Andrew demolished a breeding facility, allowing a number of the reptiles to escape. The exotic pet trade is also thought to have allowed some snakes to escape into the wild.
Statistical studies have placed the number of Burmese pythons in Florida as high as 300,000 — a figure that suggests they can never be completely eradicated.
Efforts to scale back the snake population have, to date, only had limited success. Despite their considerable size, Burmese pythons are hard to detect because they possess what zoologists term cryptic coloration.
"They're the color of mud and palm trees and detritus and leaves," said Hart. "And they're quiet."
This study was published in the journal Animal Biotelemetry.