Swimming in two plastic bins inside a brightly lit and sterile quarantine room at a Rhode Island zoo, 16 quarter-sized turtle hatchlings represent a growing worry for conservationist Lou Perrotti.

These eastern musk turtles, known for spending much of their lives in swamps and ponds and emitting a foul smell when threatened, were confiscated recently in a wildlife bust. And, though the reptiles are common, their illegal sale on the internet greatly concerns Perrotti, who directs conservation programs at Roger Williams Park Zoo in Providence.

“We are seeing an uptick in turtle poaching,” he said. “It’s getting ruthless where we are seeing thousands of turtles leaving the United States on an annual basis. … Turtle populations cannot take that kind of a hit with that much removal coming out of the wild.”

Wildlife trade experts believe that poaching — driven by growing demand for pets in the U.S., Asia and Europe — is contributing to the global decline of rare freshwater turtle and tortoise species. One study found over half of the 360 living turtle and tortoise species are at risk of extinction.

Such concerns have prompted a dozen proposals to increase protection for freshwater turtles at the 184-nation Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) meeting in Panama Nov. 14 through Nov. 25.

Precise figures on the turtle trade, especially illegal trade, can be hard to find. Based on U.S. Fish and Wildlife Service data, Tara Easter, a University of Michigan doctoral candidate who studies the trade, estimated the commercial export trade for mud turtles in the United States increased from 1,844 in 1999 to nearly 40,000 in 2017 and musk turtles from 8,254 in 1999 to more than 281,000 in 2016.

In their CITES proposal to ban or limit the commercial trade in more than 20 mud turtles species, the United States and several Latin American countries cited data from Mexico that found nearly 20,000 were confiscated, mostly at the Mexico City airport, from 2010 to 2022.

Among the world’s most trafficked animals, freshwater turtles are targeted by criminal networks that connect with buyers on the internet then transport the reptiles to black markets in Hong Kong and other Asian cities. From there, they are sold as pets, to collectors and for commercial breeding, food and traditional medicine. In many countries, trade is poorly regulated or not regulated at all.

The lucrative business — some turtle species coveted for their colorful shells or strange appearance can fetch thousand of dollars in Asia — adds to threats turtles already face. Those include climate change, habitat destruction, road mortality and predators eating their eggs.

Poachers are particularly problematic, experts say, because they target rare species and adult breeding females. Many turtle species, which can live for several decades, don’t reach reproductive maturity for a decade or more.

“The loss of large numbers of adults, especially females, can send turtles into a spiraling decline from which they cannot recover,” said Dave Collins, director of North American turtle conservation for the Turtle Survival Alliance. “Turtles have extremely low reproduction levels, producing a few eggs every year.”