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Home > Smart Living> Environment > World Environment Day: Saving a giant softshell turtle

World Environment Day: Saving a giant softshell turtle

How one researcher's determination to save the Cantor's giant softshell turtle in Kerala led locals and the government to join hands

A Cantor's giant softshell turtle at the Chandragiri river in Kasargod. Among the largest freshwater turtles, the Cantor’s giant softshell turtle, or Asian giant softshell turtle, can grow up to a metre in length and weigh 100kg.
A Cantor's giant softshell turtle at the Chandragiri river in Kasargod. Among the largest freshwater turtles, the Cantor’s giant softshell turtle, or Asian giant softshell turtle, can grow up to a metre in length and weigh 100kg. (Courtesy: Ayushi Jain)

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Ever since Ayushi Jain, a 26-year-old researcher affiliated to the Wildlife Institute of India (WII) for guidance and funding, can remember, she has been fascinated by freshwater turtles. Three years ago, she struck gold.

In the summer of 2019, as part of her master’s project, Jain went looking for a particularly rare species of freshwater turtle, the Pelochelys cantorii, in the Kuttiyadi river, near Kozhikode in Kerala. She wasn’t too hopeful; it was said nobody had seen one there since 2010. Every evening, Jain too would return disappointed.

Also read: World Environment Day: The creatures of intertidal zones

But her luck was about to change. One day, she got a call informing her that there was a big turtle bobbing in a deep pool in the Chandragiri river, near Kasargod. Jain set out immediately on the over 150km journey. A crowd had gathered along the river. Amongst dozens of dead, bloated fish, a big black-backed animal had breached the water, its small wrinkled face resembling that of a frog’s. It seemed to be the freshwater turtle Jain was looking for but she needed to be sure. She clicked some photographs and shared them with a few reptile experts.

She couldn’t contain her excitement for the day it took them to confirm it was the Cantor’s giant softshell turtle. “I happened to be in the right place at the right time,” says Jain. She shifted base from Kozhikode to Kasargod and started focusing her efforts on the Chandragiri river.

Among the largest freshwater turtles, the Cantor’s giant softshell turtle, or Asian giant softshell turtle, can grow up to a metre in length and weigh 100kg. The South-East Asian species, one of the few freshwater species which is at home in saline waters too, ranges from Malaysia to India, its westernmost boundary. Its presence in the country has been recorded only a dozen times in 20 years, with sightings being reported anecdotally from Odisha, Tamil Nadu and West Bengal.

That doesn’t mean it’s not there. in 1988, 30 turtles were recorded in a Bangladeshi fish market, indicating that they are sold for consumption. “It’s just that nobody has tried to look for and study this turtle in a focused manner,” says Jain. “All the previous records have been accidental, where researchers were looking for something else but came upon this turtle.”

There are many aspects of the turtle still unknown to science—their movement patterns, the turtle’s home range, whether they venture into the sea and come back to the river

There are no proper estimates of its population in the 11 countries it’s found in, the reason why the International Union for Conservation of Nature (IUCN) listed it as “critically endangered” in 2020. Cambodia is the only country to have released 565 hatchlings in the Mekong in 2018 as part of a nest protection programme. In addition, there has been some work in captivity in China.

This, perhaps, is why Jain’s project is so exciting—it’s the first instance of multiple records from a single river. And it has got the forest department and locals interested.

The independent researcher has intensely monitored stretches of the Chandragiri since that day in 2019. She has rowed up and down, sat on the banks in the hope of seeing a turtle when it breaches the surface to breathe, and spoken to residents along the river to gather information. She has recorded at least 10 individuals, found a nest, artificially incubated eggs and released young hatchlings in the river. Most of her sightings have been near Chandragiri’s mouth, as it drains into the Arabian Sea in Kasargod. Her efforts might just give the turtle the fillip it needs, at least in Chandragiri.

Cantor’s giant softshell turtle gets its name from Theodore Cantor, a Danish zoologist who worked for the British East India Company in the mid-19th century, collecting and describing many reptiles; the turtle was named in his honour.

The turtle inhabits slow-moving inland rivers and is thought to keep to deep depths owing to its size. It spends most of its time in the water, says Abhijit Das, a WII faculty member who studies reptiles and amphibians, especially of the Himalaya. It lays buried in sand in the riverbed, with its eyes and snout sticking out, ambushing passing fish and crabs. It is also known to scavenge on dead fish, thus becoming a natural agent in cleaning up rivers.

Jain’s research has found the turtle nests between December-February, something that wasn’t known till now. She observed a female lay about 100 eggs in three-four clutches over nearly half a metre excavated deep pits in the sand.

Turtles inhabit both land and water— the areas connecting the two are some of the most anthropologically altered spaces. A female turtle requires long stretches of undisturbed sandy banks along a river to lay eggs. This natural material is fast disappearing from the banks of the Chandragiri. “There used to be 2-3m wide sandbanks for the turtles to come and lay nests,” says Abdullah Kunji, a rubber planter from Kolathur village, near Kasargod. “But this area (near Kolathur) has been submerged under the dam.” The dam Kunji refers to is one of a series of 3-4m high check dams that have been built on the river to aid rubber and areca nut plantations and provide drinking water to villages on either side of the river.

Besides the submergence of nesting grounds, the movements of the turtles are also hampered by the check dams. A few kilometres downstream of Kolathur, for instance, is another dam, at Muliyar village. “The turtles within this stretch are stuck between two dams,” says Kunji. According to him, the dam shutters are 12 inches wide, providing enough room for turtles to get through. But the dam authorities open the shutters only 3-4 inches ajar to conserve water. In 2012 and 2014, Kunji saw a couple of turtles get stuck and die. He didn’t know much about the species at the time, so he only told the forest department about this two years ago. “There should be space for it to lay eggs and move freely,” says Kunji now. “If this situation continues, the future is bleak.”

A Cantor's giant softshell turtle hatchling.
A Cantor's giant softshell turtle hatchling. (Courtesy: Ayushi Jain)

“Even if we secure the river we might be able to save the turtle,” says Das. Ajithkumar C.K., assistant conservator of forest of the north circle of the Kerala forest department, is keen to secure the future of these turtles. “As of now, we are trying for ex-situ conservation, where we would be artificially hatching the eggs in optimum ambient temperatures,” he says.

Now that Jain’s research has helped them understand when these turtles nest, they hope to be able to monitor and protect the eggs, digging them out and transferring them to a facility planned on the riverbank for artificial incubation. The hatchlings would then be released in the river. Such a programme is more viable when an animal produces a large number of eggs, as these turtles do. “This sort of approach may give a boost to the population and might be the turtle’s most immediate need,” says Das.

For, unfortunately, their nesting period coincides with the dam gates being closed for irrigating fields, so the nests get flooded. In this case, in-situ conservation—which involves “conservation of breeding or nesting grounds and recovery of wild populations in their natural habitats”—is difficult, given the flooding and the fishing nets in which the turtles get entangled, says Ajithkumar.

In the longer term, what’s also needed is a greater level of engagement and negotiation with the local communities as well as sensitisation of the irrigation department. While the pandemic brought such work to a halt, Jain and Ajithkumar are taking the help of locals like Kunji currently to ensure the turtle eggs hatch. They plan to reach out to fishers and plantation owners too.

Ajithkumar credits Jain for throwing light on the species. “The importance of the turtle was unknown even to the forest department,” he says. Jain’s effort has led to government, society and science coming together.

There are many aspects of the turtle still unknown to science—their movement patterns, the turtle’s home range, whether they venture into the sea and come back to the river. “These are big questions to find answers to,” says Das, who believes the turtle can be a mascot for conservation, beyond the popular ones of tiger, lion, elephant. “You have a species which is its only known population, is threatened but is ecologically important, and can be a model for other poorly known riverine turtle species in the country,” he adds. “It would be a full set of conservation goals that will be achieved by protecting this species.” For this to happen, the turtle needs all the help it can get.

Vrushal Pendharkar is a Mumbai-based environment journalist.

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Sea turtles of India. Out of seven species of sea turtles found worldwide, five visit the waters around the Indian subcontinent.
Sea turtles of India. Out of seven species of sea turtles found worldwide, five visit the waters around the Indian subcontinent. (Text: Anirudh Nair, Design: Diviya Mehra)

(This illustration was first published in RoundGlass Sustain, a treasure trove of stories on India’s wildlife, habitats and their conservation)

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