Rock Springs Junior High School biology teacher Dan McCarron holds an alligator snapping turtle caught recently in Meadow Lake near Pinedale. The turtle is native to the southeastern United States and is one of the largest fresh-water turtles in North America. It is one of many exotic species people have let go in Wyoming’s open spaces.
There it was, somewhere between Baggs and Interstate 80, plodding through a barrow pit on the side of the highway: a 70-pound African spur-thigh tortoise.
A friend of Rock Springs biology teacher Dan McCarron stopped in his tracks. He knew it couldn’t be from here, so he heaved it in the back of his truck last year and brought it to McCarron.
McCarron recognized it immediately. In sub-Saharan Africa, where the boney creatures are native, the males can grow to a hefty 200 pounds.
He didn’t have space in his classroom for the tortoise – which can grow to be some of the largest in the world and are professional diggers – so he found a private collector that wanted it.
few nights in Wyoming’s chilly air and it would have died. Most imported exotics meet that kind of fate in cowboy country.
But some don’t, and the ones that stick around can have lasting impacts on the environment, said Mark Zornes, Green River wildlife management coordinator.
With each population boom, it seems, comes more exotic species, Zornes said. Releasing captive, nonnative species into the wild is not only often cruel for the animal, but can be devastating to Wyoming’s ecosystems.
A keeper of exotics
Turtles aren’t native to Wyoming west of the Continental Divide, Zornes said. East of the divide, ponds and wetlands harbor a variety of turtles, including snapping, painted and Western spiny softshell turtles.
No outdoor spot in the state can sustain an African spur-thigh turtle, or, found most recently, an alligator turtle.
A Game and Fish technician recently found an alligator snapping turtle in Meadow Lake near Pinedale. Not only are they exotic and invasive in Wyoming, they’re threatened in most of their native range in the southeastern United States.
“You can’t buy them in pet stores, and it’s possible it was brought from where it was protected,” Zornes said.
The gnarly-looking turtle with a shell that could be straight out of a Mad Max movie weighed less than 20 pounds. They can grow up to more than 200 pounds and are one of the largest fresh-water turtles in North America.
“His head was as big around as my calf,” Zornes said.
And they can live to be more than 100 years old.
That is one of the reasons why Zornes thinks creatures like the alligator turtle are released into a wild they were never meant to occupy.
“When we pick up new folks, they bring their pets with them,” he said. “Rarely do I think it is a malicious act.”
People probably think turtles belong in the outdoors, so when they can’t or don’t want to care for them anymore, they release them.
Zornes gave the alligator snapping turtle to McCarron, who ultimately passed it along to someone who wanted to keep it and give it a home.
The first odd creature someone gave McCarron was an eastern box turtle found in Rock Springs about 15 years ago. It is native to the eastern United States. McCarron let one of his students take it home as a pet.
This spring, a student found an Amazon parrot in a tree outside his front yard. No one claimed it, so the student adopted it as his own.
In June, McCarron received a baby albino corn snake someone found in a garden in town. It was only 10 inches long and may have hatched in the garden.
McCarron doesn’t know if an adult corn snake laid eggs that hatched, or if a baby somehow escaped someone’s home.
It’s possible the nonnative snake could live in Wyoming.
“You have these examples, and that’s just in Rock Springs,” McCarron said. “Who knows what people are turning loose all over the country.”
Wyoming’s ecosystem isn’t as susceptible to exotic species as places like the Everglades or Hawaii, where animals like the Burmese python and mongoose are wreaking havoc on delicate natural balances. It’s often too cold here to support some of the stranger species in the pet trade, McCarron said.
“Any exotic animal would have a hard time surviving in Wyoming because of our harsh winters,” he said. “You’re sentencing them to death.”
That doesn’t mean Wyoming is immune to invasive species. Years ago a couple of people who liked to fish for burbot introduced them into the Big Sandy River system. The predatory fish found their way into the Green River and then into Flaming Gorge Reservoir, Zornes said.
No fishing limit exists on burbot in Flaming Gorge. Annual derbies try and kill as many as possible, but it still thrives, feeding on other species that haven’t evolved to survive with them.
Diseases and parasites are another major concern with releasing pets into the ecosystem, said Zach Walker, a Game and Fish Department herpetologist.
Some nonnative species have, over time, become what some call naturalized, Walker said.
Species like brown, rainbow and golden trout are good examples. None are native to Wyoming, but all have found their niche in our ecosystem, sometimes in waters where no fish had existed before.
But opportunities for a new species to find a naturalized role without pushing something else out are slim. Rarely are new species formally introduced into the state anymore. Too many unknowns surround a new introduction of a novel species.
The result may take years to discover, like burbot in Flaming Gorge or brook trout in some of Wyoming’s native cutthroat streams. And once it is found, Walker said it is often too established to effectively defeat.