Batagurs Hit the Beach: A 2021 Nesting Recap

By Jordan Gray

Of the 359 living species of turtle and tortoise, more than 70 are considered Critically Endangered. Of those, all six species of the genus Batagur, the large river terrapins and roofed turtles of South and Southeast Asia, are included. One, the Northern River Terrapin (Batagur baska), today is represented in the wild only by a small handful of remaining individuals. Another, the Burmese Roofed Turtle (Batagur trivittata), with a little more than that. All are dependent on human intervention for survival.

All six species of the genus Batagur, ranging across South and Southeast Asia, are considered Critically Endangered by the IUCN/SSC Tortoise and Freshwater Turtle Specialist Group.

Every year between the months of December and April, TSA and our partners anxiously await nesting female Batagurs as they emerge from their rivers and estuaries, just as their species have done for countless generations. From the Chambal River in India to northeast Sumatra, sand bars and beaches become alive with field teams, anticipating their annual appearance. These teams perform nest patrols, excavate nests, and translocate eggs to protected hatcheries. From year to year, one cannot estimate the number of nests that will need to be safeguarded. In some years the field are inundated by nesting activity; in others, perhaps a single clutch will be deposited, or none at all. Still, the field teams continue the same unrelenting search effort. They are, after all, the only hope these turtles have to survive.

An adult female Painted Terrapin from Langkat Regency, North Sumatra, Indonesia.

Batagur nesting begins in Sumatra with the Painted Terrapin (Batagur borneoensis). For the Painted Terrapin, the onset of the monsoon season triggers breeding and nesting activity. From December to February, the field teams, led by Joko Guntoro (Satucita Foundation), get to work, patrolling the beaches of Aceh Tamiang and Langkat regencies in northeast Sumatra. Despite the fact that Painted Terrapin nesting season coincides with monsoon season, the teams are most successful at locating terrapin nests on cloudless nights. Following female terrapin tracks in the sand, the teams excavate and translocate eggs to the hatchery housed at the Painted Terrapin Information Centre in Pusung Kapal. This year, the teams translocated 654 eggs, just shy of 2016’s record.

Satucita Foundation turtle team members patrol the beaches of Aceh Tamiang and Langkat throughout the months of December – February.

In Malaysia, all hopes for a successful year of Southern River Terrapin (Batagur affinis) egg translocation were nearly lost. In late December, just prior to the January-March nesting season, Northeast Monsoon Winds swept over the South China Sea bringing with them pounding rain to Peninsular Malaysia. By the first week of January, many eastern Malaysian states were experiencing severe flooding, especially Terengganu. After more than a week of incessant rain, villages were underwater and uprooted citizens were fleeing their homes for evacuation centers. In the early morning hours of January 8, 2021, floodwaters and silt engulfed the village of Pasir Gajah along the Kemaman River, home to TSA partner Turtle Conservation Society of Malaysia (TCS). TCS, co-founded and managed by Pelf-Nyok Chen, is the greatest hope the critically endangered Southern River Terrapin has for survival in eastern Peninsular Malaysia.

Reformed turtle egg collectors and staff of the Turtle Conservation Society of Malaysia (TCS) translocate Southern River Terrapin eggs from nesting beaches along the Kemaman River to the hatchery at the TCS.

Less than a week after the floodwaters receded, turtle conservation was already back on the minds of TCS staff. Using heavy machinery, they cleared paths from the village to the river where the River Terrapin nests on its sandy banks. Three weeks later, the first female terrapins emerged from the Kemaman River to lay their eggs. By the end of the nesting season, TCS had 627 translocated eggs under incubation. Thanks to the dedicated TCS team, hope remains.

In Cambodia, the Wildlife Conservation Society / Royal Government of Cambodia Fisheries Administration / TSA Southern River Terrapin nest protection program on the Sre Ambel River had high hopes of replicating last year’s success. In 2018, the only known nesting beach of the Southern River Terrapin in the country was destroyed by an industrial sand mining operation. The following year, however, torrential rains brought major flooding to the Sre Ambel region. With the flooding came sands deposited from further up river, replenishing the sand bar nesting habitat. In 2020, a record three female terrapins nested on the newly-formed beach, resulting in a record 23 hatchlings. Unfortunately, the 2021 nesting season would not yield the same success. Despite 24-hour surveillance, the team, led by Long Sman, detected crawl tracks from only one female. She did not, however, deposit any eggs.

The Southern River Terrapin is arguably one of the most striking turtles on Earth, with males exhibiting golden eyes against stark black skin of the face and neck during breeding season.

Although the wild nest detection and protection program on the Sre Ambel yielded no nests in 2021, a historic event occurred at the Koh Kong Reptile Conservation Centre in Koh Kong, Cambodia. There, a captive-managed colony of hundreds of Southern River Terrapins helps assure the species survives, and serves as the source population for wild reintroductions. This year, though, female headstarted Southern River Terrapins laid eggs in captivity in Cambodia for the first time. Images obtained from camera traps confirmed that five clutches of eggs were laid by five individual terrapins. The 71 eggs are under incubation in a makeshift sand dune, with hatching expected in May. Concurrently, at the Angkor Center for Conservation of Biodiversity (ACCB), a single female Southern River Terrapin also deposited a nest. The captive reproduction of Southern River Terrapins in Cambodia marks a new era for the species.

Camera traps installed by Chris Poyser, Sitha Som, and Steve Platt capture a nocturnal image of one of the five female Southern River Terrapins to nest at the Koh Kong Reptile Conservation Centre this year, a program first.

Nearly 2,000 kilometers to the northwest, in the vast wetlands of the Sundarbans of Bangladesh and India, the nesting season for one of the world’s most endangered turtles, the Northern River Terrapin (Batagur baska), was also underway in February and March. The Bangladeshi program was conceptualized and continues to be operated by TSA partner Zoo Vienna Schönbrunn, in collaboration with the Bangladesh Forest Department, Turtle Island, and Prokriti O Jibon Foundation. This program maintains two assurance colonies for Northern River Terrapins, one at the Karamjal Forest Station and the other at Bhawal National Park. Each facility’s breeding population includes four adult females painstakingly sourced from across Bangladesh.

Fluorescent strips are affixed to female terrapins in Bangladesh so that specialized surveillance cameras can detect nocturnal nesting activity.

This year, the first clutch of eggs was deposited at the Karamjal Forest Station on February 28, the program’s earliest nesting on record. Since that first nesting event, a total of five clutches have been deposited, three at Karamjal and two at Bhawal, totaling 137 eggs. Even better, this is the first time that three separate females have laid eggs at Karamjal, meaning that one female laid her eggs there for the first time. This is big news as it is expected to increase genetic variation in the captive population.

The Project Batagur Baska program in Bangladesh experienced another successful year of nesting activity, including an adult female laying her first clutch of eggs since her inclusion into the assurance colony at the Karmajal Forest Station.

Westward, in India, the nesting season for the Northern River Terrapin made a fashionably late entrance. By the time nesting began at the assurance colony at the Sajnekhali Tiger Reserve (STR), situated due west of Karamjal Forest Station, nesting was already wrapping up in Bangladesh. Not to be outdone by their Bangladeshi counterparts, the female terrapins at STR deposited a total of 90 eggs amongst four nests, a significant increase from 2020’s reproductive output.

Sexual dimorphism is marked in the genus Batagur, with males, such as this Burmese Roofed Turtle, expressing exceptional pigment enhancement during the breeding season.

In Myanmar, the Burmese Roofed Turtle (Batagur trivittata) nesting season saw a mixed bag of success, disappointment, and, ultimately, danger. In the middle of nesting season, on the morning of February 1, a coup d’état began, in which the Tatmadaw, Myanmar’s military, seized power and deposed the democratically elected members of the country’s ruling party. Although the TSA/WCS/Forest Department programs are still up and running, leader Kalyar Platt has been sequestered to her home along with her family, and Steve Platt is relegated to Cambodia, having no access into Myanmar since the beginning of the COVID-19 pandemic.

Detecting and excavating Burmese Roofed Turtle nests along the upper Chindwin River is no easy task, especially considering the females deposit a single clutch amongst multiple chambers.

Despite this distressing situation, nest patrols continued as usual along the upper Chindwin River, where the last remaining wild Burmese Roofed Turtles reside. Unfortunately, the previous years’ success was not witnessed this year, with only a single nest deposited along the river’s sandy banks. However, the breeding assurance colony at the Yadanabon Zoo—one of four in Asia—has deposited clutches, and we anxiously await the hatchlings’ emergence. On a bright note, on April 12, a hatchling Burmese Roofed Turtle was discovered at the assurance colony at Lawkanandar Wildlife Sanctuary. This is the first occurrence of roofed turtle reproduction at the Sanctuary, which was founded in 2010.

The rainbow of the turtle world, the Red-crowned Roofed Turtle clings to existence in India’s Chambal River where our nest protection program serves as its last lifeline.

Finally, in northern India, the conservation program for the Red-crowned (Batagur kachuga) and Three-striped (Batagur dhongoka) roofed turtles of the Chambal River continued its 14th year. The Chambal River is the last remaining stronghold for both species. However, anthropogenic threats such as clandestine fishing, egg poaching, and nest predation keep the population of Red-crowned Roofed Turtle (the more endangered of the two) teetering on the brink of collapse.

A female Three-striped Roofed Turtle basks on the banks of the Chambal River. To date, approximately 100,000 hatchlings of this species have been released into the Chambal.

To offset declines, the TSA-India program engages in an annual five-month effort to locate nests, transfer eggs to riverside hatcheries, guard incubating eggs, and release hatchlings. All told, roughly 120,000 hatchlings have been released into the river to date. This year saw another season of success, as the team detected and translocated 712 Red-crowned and 5,860 Three-striped roofed turtle eggs to the hatchery. There, they are currently under round-the-clock surveillance until their expected hatching next month.

For five straight months, and often under scorching temperatures, team members of the Chambal program translocate Batagur eggs to the protected hatchery along the river’s bank and provide round-the-clock protection while they incubate.

The TSA and our partners across South and Southeast Asia are committed to the persistence of wild Batagur turtles. With all species considered Critically Endangered, our steadfast resolve must continue unabated. Although challenges lie ahead, the survival of this group of charismatic turtles is in our hands. Together, we can ensure that Batagur turtles survive in the wild for years to come.

Stay tuned for our hatchling update this summer!

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