About half of the world’s turtle species face possible extinction due in large part to a growing demand for turtles as a popular dining delicacy and a source of traditional medicines. Sixty of the world’s leading experts on freshwater turtles reached that conclusion at a special gathering in Nevada this month. The phenomenon described as a “turtle survival crisis” was the most urgent topic at a prestigious international conference held in Laughlin, Nevada, August 13-15. The Powdermill IV conference, also discussed freshwater turtle ecology, behavior, systematics and conservation.
“We are on the brink of losing a group of animals that has managed to survive the upheavals of the last 200 million years, including the great extinction episode that eliminated the dinosaurs,” said Dr. Russell Mittermeier, president of Conservation International and an expert on turtles.
“Turtles are apparently at comparable risk as the world’s declining amphibians yet they have not received the same level of attention,” said Dr. Jeffrey Lovich, spokesperson for the researchers, co-organizer of the workshop, and a scientist with the U.S. Geological Survey. “Nearly half of all known species of turtles are considered to be at risk and threatened,” he said.
“We have done a good job of educating the public about the plight of amphibians, but like them, reptiles such as turtles, need protection too,” said Dr. Whit Gibbons of the Savannah River Ecology Laboratory. “Partners in Amphibian and Reptile Conservation (PARC) has begun to address this whole class of threatened animals. If turtles are to be saved, it will have to be through cooperative efforts, such as PARC.”
“While many people are aware that sea turtles are endangered, few realize that many freshwater turtles and tortoises, several with very restricted geographic ranges, face an even more critical situation,” said Dr. Peter Pritchard, director of the Chelonian Research Institute and vice chairman of the Tortoise and Freshwater Turtle Specialist Group.
“Many giant tortoises on oceanic islands have already been driven to extinction over the last three centuries because of human exploitation. So far, freshwater turtles have come through this century with the documented extinction of just one subspecies, a small mud turtle from Mexico. However, all sea turtles, most remaining tortoises, and many freshwater turtles are endangered or threatened and require urgent conservation action. Some 12 turtle species are considered critically endangered, facing a high risk of imminent extinction unless long-term population trends are reversed,” said Dr. Anders Rhodin, director of Chelonian Research Foundation and co-sponsor of the conference.
“Turtles are threatened in the United States as well. About 55 species of turtles, or approximately 20% of the world’s total turtle diversity, are in the United States. Of these, 25 species (45%) require conservation action, and 21 species (38%) are protected, or are candidates for protection,” said Lovich.
The turtle researchers found a striking contrast between the “declining amphibian phenomenon” and the “turtle survival crisis.” The main causes of declines in amphibians are associated with ecological change. The turtle decline seems first and foremost to be driven by human consumption. The wealthy eat turtles as a luxury food item especially in Southeast Asia. In places like Madagascar and Mexico, they are eaten by the very poor, for subsistence. Some 50 percent of the total number of threatened turtles are at risk due to this type of exploitation.
The Southeast Asian trade is driven by an enormous and growing demand from China, where age-old traditions of consuming turtles for food and as medicine are growing dramatically with increased affluence and the recent convertibility of Chinese currency. Some of the most desired species fetch as much as $1,000 in Southeast Asian markets. Scientists often discover turtles that are rarely seen in the wild in open markets and restaurants. “Although much of this is being done in the name of tradition, it now threatens the survival of a globally important group of animals. In light of the severity of the problem, this use of turtles should be stopped,” said Mittermeier.
This trade has hit already depleted turtle populations in Southeast Asian countries particularly hard. China’s own turtles are already decimated. Several Chinese species only discovered in the last two decades are possibly extinct due to high demand. Vietnam, Bangladesh and Indonesia are exporting large numbers of turtles to China and this unsustainable trade now seems to be extending to other countries as well. Indeed, well over 7 million turtles of several species are exported every year from the United States, as pets or food products. Turtle species in the United States often receive little or no protection. In all, nearly 50 species of turtles worldwide are affected by this trade.
“Of particular concern are some of the large, slow-growing river turtles, with large females being among the most impacted,” said Pritchard. “Many turtle species are unlikely to survive the onslaught of human exploitation and habitat loss if current trends continue. As we enter the next millennium, there is a great risk that a number of turtles will become extinct, particularly in Southeast Asia.”
The scientists called for the following measures to address the turtle survival crisis:
o Existing conservation trade laws and regulations must be enforced to ensure thorough and ongoing monitoring of the turtle trade, including numbers of animals, origins, and destinations.
o Dialogues should open among international scientists and policy makers with Chinese authorities and other exporting nations to encourage much more effective national trade controls.
o U.S. regulatory agencies should substantially increase import and export regulations and enforcement related to the international trade of freshwater turtles.
o Non-governmental conservation organizations should develop turtle conservation strategies.
o Captive breeding should be undertaken for some of the most endangered species, while the underlying problems that caused the declines are being addressed.
Profiles of Turtles in Trouble
o Just a decade or two ago, the three-striped box turtle Cuora trifasciata was sold in Hong Kong markets and in the American pet trade for a handful of dollars. This attractive, semi-terrestrial species, (10-11 inches long) is found in Laos, Vietnam and southeastern China, including Hong Kong and Hainan Island. In China, the species is considered to be a cure for cancer and to have other medicinal properties, and now fetches $1,000 to $1,500 per turtle. Buyers particularly seek specimens caught in the wild, driving collectors out in search of this declining species.
o Geoemyda yuwonoi, one of the most poorly-known and rarest turtles in the world, is a medium-sized forest-floor or leaf-litter species first described in 1995 and found in a limited area on the Minahassa Peninsula of Sulawesi, Indonesia. Within a year of its discovery, specimens were showing up in numbers in food markets in mainland China. The species, which does not thrive in captivity, may well become extinct within just a few years of its discovery.
o Swinhoe’s softshell, also known as the Hoan Kiem turtle, is found inland from Shanghai, China and from northern Vietnam. It was described over a lO0 years ago but little is known about it. It is probably the largest freshwater turtle in the world, adults reaching about ll0 cm (42.9 inches) in shell length. So few individuals remain alive that it is functionally extinct. Live specimens are extremely rare finds in Vietnam, and most are sold for food or die quickly in captivity.
o Since the mid-1970s, fishing pressure for domestic markets has reduced the number of healthy populations of freshwater turtles in Veracruz, Mexico from seven or eight species to two species. The only intact populations are notably small species (about four inches at maturity), Claudius angustatus and Kinosternon acutum. Populations of the tropical snapping turtle, the Mexican slider turtle, the giant musk turtle, the white-lipped mud turtle, and the very large Central American river turtle have all collapsed with only occasional sightings of individuals.
o In China, “thousand year turtles” as they are known, are slaughtered and eaten by people seeking to extend their longevity. The species, one of the largest of the pond and river turtles of Southeast Asia, Orlitia borneensis, is a little-studied species that can reach a shell length of 70-80 cm (27.3-31.2 inches) and may be 20-30 years old when it reaches adulthood.
o Map turtles, found only in the U.S. (genus Graptemys), are especially at risk. A popular species with hobbiests, they are threatened by pollution and “plinking” a popular pastime that uses turtles for various types of target practice. Two of the 12 currently recognized species are protected under the Endangered Species Act. Nine of the l2 have small ranges, occupying specific habitat such as a single river, making them especially vulnerable to extinction from disasters such as toxic spills.
o Turtles of the North American genus Clemmys, the bog turtle, spotted turtle, wood turtle and western pond turtle, are all popular in the pet trade. The bog turtle has been called the “Cadillac” of turtles and sells on the international hobbiest market for as much as $1,400 per pair, despite its status as a federally protected species under the Endangered Species Act.
Editor’s note:The 5th meeting in the Powdermill series is tentatively planned for 2002 in Brazil and organized by Dick Vogt.