Bringing turtles back from the brink

The most recent discoveries of a female leatherback coming ashore to lay her eggs last month in Phang Nga province not only brought joy to conservationists but are also helping to shape future restoration plans for the endangered species to ensure that they will return to the Thai shores year after year.

“We’re glad to learn that leatherback is once again using the beaches in the Andaman Sea for nesting. We hope more will come this season,” says Hirun Kanghae, senior marine biologist at Phuket Marine Biological Center (PMBC), and leader of the center’s mission – to bring the threatened species including leatherbacks – back from the brink of extinction.

Photo: A group of officials attached to Marine and Coastal Resources Office 6 investigate a leatherback turtle nest.

It’s believed that there are fewer than 10 nesting female leatherbacks left in Thailand.

There are seven species of sea turtles in the world, five of them found in Thai waters: the Leatherback, Green Turtle, Hawksbill Turtle, Olive Ridley Turtle and Loggerhead Turtle.

The leatherback turtle is the largest sea turtle on earth, weighing up to 900 kgs and reaching lengths of up to 2.5 meters. They feed primarily on jellyfish as well as seagrasses and algae.

The leatherbacks are a rarity in Thailand mainly due to human activities, fishing gear, plastic pollution and the impact of global warming which can damage habitats and even alter the sex ratios of the animals.

They are listed as vulnerable globally on the International Union for Conservation of Nature Red List but many sub-populations are deemed critically endangered.

The leatherbacks are classified as a “preserved” species, a more critical status, under Thailand’s Wildlife Preservation and Protection Act B.E. 2562 (2019).

Collaborative conservation efforts

Last month, four leatherback nests along with the mother’s tracks indicating a turtle has emerged from the sea to lay her eggs, were observed in Phang Nga’s Kho Phra Thong District – three on Thung Dap Beach and another on Koh Ra Beach.

The first was discovered by a local resident on January 3 on Thung Dap Beach. An investigation found it contains 127 eggs – 82 viable, 44 infertile, and one broken.

Spotted by officials attached to Marine and Coastal Resources Office 6 during a routine patrol on January 8, on Thung Dap Beach, the second has 124 eggs – 76 fertile and 48 infertile.

On January 19, a third nest was found on Thung Dap Beach once more, containing 135 eggs – 80 viable and 55 infertile. Observed on Koh Ra Beach on January 31, the fourth, meanwhile, has 101 eggs – 69 viable and 32 infertile.

It’s believed that all the nests observed belong to the same mother leatherback.

Due to the vulnerable locations of the nests, officials have relocated the eggs, which will incubate in the sand for around 55-60 days before hatching, to safer locations.

Hirun says stronger baby turtles will make their way to the ocean. Other die in the nests after hatching. The babies that cannot successfully go to the sea are nursed at the center.

Only 0.1-0.2% of hatchlings will survive to adulthood under natural conditions, he adds.

The PMBC launched a captive-rearing initiative in 2019 to nurse the weak baby leatherbacks. The hatchlings are reared in ponds at the center and kept alive for over a year in captive conditions.

Thailand is among five countries that have been able to nurse this species of baby turtle up to their first year.

Photo: Officials attached to Phuket Marine Biological Center together with Upwell team members prepare to release a year-old leatherback turtle into the wild.

The centre has worked with Upwell Turtles, a non-profit organization based in the United States committed to protecting and recovering endangered populations of turtles through research and conservation actions.

This collaborative effort aims to use innovative tools to track sea turtles in the ocean and monitor their movements and behaviors in order to protect them.

In April 2024, 11 captive-reared baby leatherbacks, each around one year old, were equipped with tiny micro-satellite tags on their backs and released into the Indian Ocean.

Photo: A year-old leatherback turtle swims in the sea with a tiny satellite tag on its back.

The tags are used to collect data about their progress after release.

“Using the tools, we can learn where they go after being released into the wild and how they use marine habitats. To this end, we can better understand the marine reptiles and improve protections for them at sea,” Hirun says.

He adds that an additional 25 baby leatherbacks would be fitted with the tags and then released this year, again with Upwell’s support.

In addition to its rearing program, the PMBC has teamed up with beach hotels and a sea turtle network supported by more than 50 organizations including coastal community members to initiate the ‘Saving Sea Turtles’ program to protect the endangered species.

Hotels are encouraged to reduce the amount of artificial light they use that is visible from nesting beaches and minimize disturbances caused by humans including parties.

The community members are inspired to always keep the beach clean, which can promote successful nesting and hatching.

“Sea turtles often return to the beach to lay their eggs when the conditions are healthy. They don’t nest on beaches that are brightly lit, noisy and littered,” Hirun says, urging people to turn off or dim lights on the beach at night.

The program has enjoyed success and gained good cooperation from hotels and the nearby community since it was launched in 2017, the conservationist notes.

“Last year, we saw a female leatherback return to Hat Sai Khaow to lay her eggs. It’s good to learn that more and more hotels want to join the program to help save the animals,” he says.

Located in Phuket, Hat Sai Khaow (White Sand Beach) is well known as a sea turtle nesting site.

Phuket and Phang Nga are the only two provinces where leatherbacks emerge to nest. And beaches in Phuket are highly threatened by human actions, he adds.

Sea turtles increasingly endangered

According to Hirun, there has been a decline in the nesting of leatherback turtles on the nesting beaches in the Andaman Sea, from around 30 annual nests in the past 30-40 years to 10 annual nests in 2024. Indeed, only 69 nests have been observed over past seven years.

“We are losing more every day,” the conservationist says.

Sea turtles are facing numerous threats to their nesting locations and to their survival, most of them human-caused and others natural.

Boat strikes and recreational activities like speed boats and jet skis can kill and seriously injure sea turtles, prevent them from emerging from the nest and even cause the females to stop nesting, he says.

Discarded fishing gear is also one of the biggest threats to aquatic animals including sea turtles, while eating plastic waste and exposure to toxins is killing them.

“Nets left in the water can entangle and kill sea turtles and marine mammals,” Hirun adds.

Also, warmer temperatures are causing more females to be born than males, he notes, adding that temperatures of the sand affect the gender of the hatchlings.

Why do sea turtles matter?

Sea turtles serve as an indicator of the health of marine ecosystems. They also play a pivotal role in generating and maintaining diversity throughout the oceans.

The presence of sea turtles can tell how healthy the ecosystem is. When they are declining in number, this can be a warning sign of environmental problems, he says.

In addition to dugongs, he explained that green turtles help seagrasses grow by eating these plants including their seeds which pass through their gut and end up in their poop.

When the turtles poop, they help disperse or spread the seeds of seagrasses to the sea bed, helping them grow.

Seagrass meadows are a source of food for dugongs, which are threatened by seagrass habitat loss, as well as turtles and other aquatic animals.

The plant also helps prevent erosion and provides homes for marine life like shrimp, crabs and economically important fish species.

Hirun explains that the loss or decline of seagrasses will affect local fisheries and consumers, who are paying higher prices for seafood.

Leatherback sea turtles are a natural predator of jellyfish and that can help improve safety in tourism, he notes.

The populations of jellyfish in Thai waters are increasing every year. The number of tourists who have sought treatment for jellyfish stings while swimming in the Gulf of Thailand and the Andaman Sea is also on the rise.

There have been at least 48 cases of serious injuries and deaths caused by box jellyfish in Thai waters since 2000, according to a report by the Department of Disease Control.

The health of the ocean is closely connected to the health of people, Hirun says, adding that consumption of contaminated seafood can lead to human health concerns.

“Stop littering and avoid activities that cause climate change to help save the ocean and marine life including sea turtles,” he adds.