Giant, non-native snakes like the Burmese python and the yellow anaconda have been menacing Florida residents in recent months. But the problem could become a national one.
According to a U.S. Geological Survey report released Tuesday, nonnative snakes like the Burmese python could slither their way north from the warm, humid conditions of South Florida.
The big snakes threaten native species and ecosystems because they mature and reproduce quickly, travel long distances and can eat almost anything in fur, feathers or scales, experts say.
Foreign snakes are already threatening other states in the continental United States. At least four populations of three different species of eastern watersnakes are established in California. The 302-page report notes that "as a generalist predator, water snakes, like the constrictors, represent a potential threat to small prey species of conservation concern, and may compete with native endangered species."
The U.S. Geological Survey report could be a step toward a ban on importing constrictor-like snakes into the U.S., said Ken Warren, spokesman for the U.S. Fish and Wildlife Service's South Florida office. The FWC will now evaluate the report and seek public comment before recommending such a ban.
"In many aspects, the report confirms what we already knew: that these snakes are a problem and that they do pose some risk," Warren said.
The report analyzed nine kinds of snakes. Five — Burmese pythons, northern and southern African pythons, boa constrictors and yellow anacondas — are of "high risk" to the ecosystems of the U.S., especially in Florida. Scientists are already studying where Burmese pythons can survive in the U.S. Seven are being studied in a natural enclosure in South Carolina to see if the tropical natives can live through colder winters.
The number of invasive pythons in South Florida and throughout Everglades National Park has exploded in the past decade to potentially tens of thousands, though wildlife officials aren't sure exactly how many are out there.
Scientists believe pet owners have 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.
Officials say the constrictors can produce up to 100 eggs at a time. Dr. Robert Reed, a research biologist with the U.S. geological survey, said everything from small wood storks to alligators and bobcats have been found in the stomachs of dead pythons.
Reed said the native animals of Florida aren't used to living near super-predatory snakes, and in time, entire wildlife populations could be wiped out.
"The fear is that something will happen akin to the situation with brown tree snakes on Guam," said Reed. "There, within 40 years of arrival, the snakes wiped out 10 of 12 bird species on island."
Reed was quick to point out that these free-range snakes pose a "minuscule" threat to people.
"All of the known fatalities involving giant snakes are from pet snakes, and usually to the owners," he said. In July, an 8-foot pet python strangled a toddler in Central Florida.
Officials have tried to crack down on the invasive species; this summer, the Florida Fish and Wildlife Conservation Commission announced that the state would allow a few permitted snake experts to begin hunting, trapping and killing the nonnative pythons in an effort to eradicate them. Hunting the snakes is not allowed in Everglades National Park.
Between Jan. 1 and Oct. 5, some 270 Burmese pythons have been removed from the park.
"It's just very difficult to eradicate them," said Linda Friar, a park spokeswoman. "The snakes are very difficult to locate."