29-05-2025
North America's tiniest turtle is at risk. Zoo Knoxville is helping improve its odds
North America's tiniest turtle is at risk, with a dwindling population and shrinking bog habitat. Zoo Knoxville's work gives the species a better chance at survival.
The increasingly rare reptile is the bog turtle, an animal known for its small size − growing to only about 4 inches long by adulthood − and secretive behavior.
"Everybody involved in bog turtle work gets very, very secretive and very protective about the bog sites, just because the illegal pet trade and poaching is an issue with these guys, because they are a very cute, adorable turtle," said Charlotte Carruth, who is the lead keeper in Zoo Knoxville's bird department, but also works in the herpetology department.
"So everybody keeps their sites very secret and protected. So I can say they're in Eastern Tennessee at high elevation, but that's about as much as I can say."
Their wetland habitat of bogs and fens is sparse to begin with. "There's still not a lot known about (bog turtles) just because mountain bogs are one of the rarest environments and ecosystems to find," Carruth said. Today, these sites are increasingly at risk, as they're often cleared and drained for other uses, Carruth said.
There are two bog turtle populations, the northern bog turtle and southern bog turtle, the latter of which are now known to live in Georgia, North Carolina, South Carolina and Tennessee, with the majority in North Carolina.
The northern bog turtle was classified as threatened under the Endangered Species Act in 1997, according to Will Harlan, southeast director and senior scientist at the Center for Biological Diversity, a nonprofit that focuses on conservation.
The organization is working to grant the southern bog turtle similar protections. In November, the Center for Biological Diversity sued the U.S. Fish and Wildlife Service for delaying Endangered Species Act protections for the southern bog turtle, according to a news release.
In April, the two entities reached an agreement requiring the U.S. Fish and Wildlife Service to make a decision about the protections by October 2028.
While all bog turtles face the risks of poaching and a habitat that grows increasingly rare, a proposed change to the Endangered Species Act puts threatened bog turtles further in danger. The proposed rule from the U.S. Fish and Wildlife Service and the National Oceanic and Atmospheric Administration would redefine "harm" in the act so that it no longer includes habitat modification, meaning the act would no long protect the habitats of endangered species.
Zoo Knoxville has been working with bog turtles since 1986, when former curator of herpetology Bern Tryon helped discover them in Tennessee, Carruth said.
Through a collaboration with state and federal agencies such as the Tennessee Wildlife Resources Agency, North Carolina Wildlife Resources Commission and U.S. Fish and Wildlife Service, Zoo Knoxville conducts a "head-start" program that improves the turtles chances of surviving in the wild.
Eggs are collected from bog sites and brought to Knoxville, where they are hatched and raised for about a year. In the wild, bog turtles are dormant during the winter months, but at the zoo, they're kept warm and awake.
Unlike their wild peers, the head-start turtles can use this time to eat and grow. They're fed crickets, earthworms, phoenix worms and isopods, sometimes coated with calcium powder for extra nutrients, and kept at the Clayton Family Amphibian Reptile Conservation Campus in a miniature bog habitat complete with heat lamps and UV-B lighting.
When they're released, the zoo's turtles are about the size of a 3-year-old turtle raised in the wild, giving them a better chance of survival. This year, 34 bog turtles were raised by Zoo Knoxville and are slated to be returned to their natural habitat in June. The head-start team will be able to continue to monitor them with the help of special markings, a painless notch cut into part of each turtle's shell.
Since the program began, about 280 bog turtles have gotten their start in life at Zoo Knoxville and been returned to the wild, according to Zoo Knoxville's website.
Hayden Dunbar is the storyteller reporter. Email
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This article originally appeared on Knoxville News Sentinel: Tiniest turtle in U.S. is at risk. Zoo Knoxville helps protect it
