Image Source: https://news.mongabay.com/
On a late November day in the Kampong Seila district of Cambodia’s Preah Sihanouk province, 51 critically endangered freshwater turtles swam into the warm waters of the Sre Ambel River, returning to the wild. The muddy water filled with dark, sleek shells and then, within moments, they slid into the current and disappeared.
The reintroduction constitutes the latest and largest step taken to save a species known locally as the royal turtle, but globally as the southern river terrapin (Batagur affinis). This international effort began in earnest in 2000 after the Wildlife Conservation Society (WCS) and the Cambodian Fisheries Administration (FiA) rediscovered the species in the Southeast Asian nation. Once believed to be extinct in Cambodia, the southern river terrapin is still listed as one of the 25 most endangered tortoises and freshwater turtles in the world. However, the EU, WCS and FiA are all working hard to give the animal a comeback.
“It is heartening to see yet another release of the critically endangered Royal Turtle into their native habitat which signals the success of the head-starting facility and efforts led by WCS,” Dr. Sonja Luz, deputy CEO of Mandai Nature, a Southeast Asian conservation nonprofit, said in a press release. “The strong involvement from the local authorities and communities has also been critical in ensuring the turtles released can thrive in the wild.”
The rewilding process is intensive: the researchers capture the turtles immediately after hatching along the river, prepare them to survive in the wild, and then release them back into their native river systems. In addition to WCS and FiA, the program is also supported by researchers with the EU.
Since 2015, scientists have released a total of 147 southern river terrapins back into their native Sre Ambel River system, including the 51 reintroduced last November. In the latest batch, scientists microchipped and tagged each turtle — 31 females and 20 males — with an acoustic transmitter. These devices allow scientists to track and record data about the animals’ behavior in the wild.
All 51 of the recently released turtles are relatively young, between 6 and 15 years old. Developing only slightly slower than humans, southern river terrapins can live up to a century, reaching sexual maturity at age 25. The southern river terrapin’s distinctive black shells and upturned noses, together with piercing yellow eyes and relatively large size, have drawn attention for decades. Unfortunately for the turtles, however, that attention has almost driven them to extinction.
The species, like many other turtles in Asia, is threatened by poaching both for its eggs and meat. In fact, the royal turtle originally got its name because its eggs were considered a delicacy, to be eaten only by royalty. Despite being named Cambodia’s national reptile by royal decree in 2005, the turtle still faces an uphill battle back from the brink of extinction.
“Those who still trade protected species will face legal action,” said Poum Sotha, the FiA director-general.
It wasn’t just poaching, however, that led to the turtle’s population decline. According to a press release from WCS, a plethora of factors contributed — spanning everything from loss of habitat due to deforestation and sand dredging, as well as the illegal wildlife trade.
Additionally, although scientists once considered the southern river terrapins to range from India to Indonesia, research revealed that terrapins actually fall into two distinct species: northern and southern. That discovery not only dramatically decreased the number of turtles confirmed to be of the southern river terrapin variety, but it also meant their known range shrank to only southern Thailand, western Malaysia, Sumatra, and Cambodia. The norther river terrapin (Batagur baska) is also listed as critically endangered.
Still, conservation efforts, beginning with steps like nest protection programs and raising young turtles in captivity before releasing them, have proved fruitful so far.
“With the increasing number of adults in the wild through this release, we do hope that this species will breed in the wild and that annual nests will increase in the next few years,” said Sereyrotha Ken, the country director for WCS Cambodia.
On the day of the latest release, as the 51 healthy turtles returned to the wild, that hope looked well-founded — backed both by science and by people.