The 30 students in Mary Fabian’s high school science class listened attentively to biology professor Michael Dorcas’ talk about invasive species, but nobody was sitting in the front row.
Every so often, one of them glanced nervously at a blue box, about the size of a picnic cooler, in the front of the room.
Dorcas, who teaches at Davidson College, is a herpetologist who has been studying Burmese pythons in the Florida Everglades. Inside that box is an attention-grabbing visual aid for his presentation: a live python more than 15 feet long.
Fabian’s class, part of Charlotte-Mecklenburg Schools innovative “Middle College” program, meets at the Cato Campus of Central Piedmont Community College, on W.T. Harris Boulevard in University City.
Dorcas’ research in Florida has taught him to “expect the unexpected.”
“If you told me 20 years ago that we’d have one of the world’s largest snakes living in the continental U.S., I wouldn’t have believed you,” Dorcas said.
The Burmese python is native to Southern Asia. As hatchlings, they are popular in the U.S. as pets because of their bright pattern, docile behavior and the promise (threat?) that they will get impressively large.
Dorcas shows students an appealingly cute picture of a baby python curled up in its owner’s hand. Within a year or two, however, pythons aren’t cute anymore, becoming very large and requiring bigger live or freshly killed food.
A reptile-fascinated Dorcas discovered that for himself as a teen, when he bought a python for a pet. Eventually, he had to sell it, to a woman who wanted it for her dance act.
Pet owners sometimes simply release snakes into the wild when they get too large, and pets sometimes escape. Burmese pythons have found their way to Florida’s Everglades National Park, where conditions are so much to their liking that they have not only survived but thrived.
The population now numbers at least in the tens of thousands and may be much higher. Like many snakes, pythons are experts at hiding, so that for each one you see, Dorcas said, you may miss 99 others.
With python sightings increasing and public concern growing, Dorcas joined a team of scientists working to understand the scope of the problem in the Everglades.
After implanting tracking devices in some snakes, Dorcas and his colleagues discovered that the snakes can move many miles over several months and can find their way back to where they had been captured.
To assess their effects on other wildlife, Dorcas’s team used roadways through areas with and without pythons. Their chilling conclusion: Pythons are having a major negative effect on wildlife, from such common fauna as foxes, rabbits, opossums and even alligators to the Key Largo wood rat and other endangered species.
Will the pythons just keep crawling north to the Carolinas?
Dorcas said there is a good deal of controversy about whether the snakes’ range will be limited to south Florida, or whether they might spread to as much as one-third of the U.S., including parts of the Carolinas.
Another Dorcas experiment, in South Carolina, showed that Burmese pythons can survive lower temperatures than they experience in Florida but are killed by severe cold. On the other hand, Dorcas said, any that survive cold snaps may help breed a new generation of pythons better adapted to freezing temperatures.
Dorcas has already found ball pythons, a smaller relative, in Charlotte. In 2007, a ball python attacked a 15-month-old toddler in Freedom Park.
Captive pythons have already killed people, Dorcas said. A 2-year-girl was strangled in Florida by a pet Burmese python in 2009, and last year two young boys were killed by an escaped African rock python in Canada.
Though not a major risk, “It might just be a matter of time for wild pythons,” Dorcas believes.
Meanwhile, the Everglades is home to a growing list of other invasive species, including the African rock python – equally large but more aggressive than its Burmese cousin – and monitor lizards over 5 feet long.
Another exotic pest, feral pigs, has been creating problems in the Everglades and other areas across the U.S. since escaping from the Spanish three centuries ago.
Invasive species are no laughing matter, Dorcas said. He pointed to two notorious local examples, kudzu and imported fire ants.
“What difference can one introduced snake make? We’ve seen it before, and we are seeing it again,” Dorcas said. “The classic example is the impact of the brown tree snake on the island of Guam, which has about eliminated native birds there.”
It isn’t easy to control such biological invaders, Dorcas said. About the only thing that can eat a mature Burmese python is a very large alligator. Pythons make good mothers, coiling around their eggs to protect them and even vibrating their muscles to generate heat.
At the same time, the worrisome situation offers a great opportunity for scientists.
“A new apex predator has been introduced to a new continent. What better place to document the impacts than here?” Dorcas asked.
Dorcas closes his talk by opening that ominous blue box. A few students leave the room, but most come forward, cautiously at first then with greater eagerness, as Dorcas carefully brings out Carmelita, a beautiful 15-foot-long female Burmese python. The snake is huge, but docile and relaxed. Students form a line to hold it up off the ground, getting a first-hand feel for the awe-inspiring creature at the center of the controversy.
Fabian, the science teacher and a UNC Charlotte graduate, organized Dorcas’s visit as part of her class’s study of sustainability. Fabian’s friendly, informal style and bright hennaed hair help her fit right in with her young students, but she’s got solid credentials: Fabian holds degrees in history, engineering and education, was twice Teacher of the Year in 2012 and 2014, and has National Board certification. She taught in conventional high schools, but said the Cato Middle College program is an ideal fit.
“It was my dream job, so I jumped on it.” Fabian said. “They would have to dynamite me out of this program. I love teaching here.”
Davidson College’s herpetology program, led by Dorcas, offers a host of educational outreach programs serving the community and research opportunities for students.
The Middle College High School Program of Charlotte-Mecklenburg Schools is an honors program for high school juniors and seniors, offering selected students the opportunity to finish high school while taking college courses at Central Piedmont Community College for credit.
The program began in 2007 at CPCC’s Cato Campus and is now offered on the Cato, Levine and (in 2015) Harper CPCC campuses. For more information about the Cato program, call 980-343-1452.