Climate change threatens sea turtle conservation in Malaysia

On a secluded beach on the island of Redang in East Malaysia, a group of volunteers carefully dig out the sand.

Their mission: move newly laid turtle eggs to a shadier, wooded spot on the beach in an attempt to ensure the eggs are incubated and hatched in cooler conditions. The move is part of efforts by conservationists in Malaysia to ensure a more balanced gender ratio among baby turtles, which is heavily influenced by temperatures during incubation.

Researchers and wildlife activists fear that rising sea and surface temperatures due to climate change could compromise efforts to protect Malaysia’s already threatened sea turtles, with observers at the Chagar Hutang Turtle Sanctuary in Redang already seeing fewer males being born in recent years.

“Any average incubation temperature above 30 degrees Celsius will result in 100% female hatch production, and anywhere closer to 28 degrees Celsius and below will result in the opposite effect of male bias,” said Nicholas Tolen, a research scientist. and PhD student at the University of Malaya, Terengganu (UMT).

Scientists at the Chagar Hutang Turtle Sanctuary on Redang Island in Malaysia are now trying to keep sea turtle eggs cool and safe by moving new nests to shadier areas. According to Tolen, this will have a positive influence on a more equal gender ratio for puppies. Now, the sanctuary is getting help from volunteers to carefully move the nests several meters from the shore to a shady strip surrounded by markers, closer to the island’s rainforest.

According to UMT researcher Mohd Uzair Rusli, it is best to incubate eggs outdoors under the shade of trees, as an artificial incubator can disrupt baby sea turtles’ understanding of the Earth’s magnetic field, causing them to lose consciousness. the direction and the ability to nest.

Conservationists at UMT, who run the Chagar Hutang Turtle Sanctuary, began relocating turtle nests years ago to provide what they believed would be a safe haven for baby turtles to hatch. At first, scientists discovered that the hot beach sand was helping to facilitate a faster and higher hatchling birth rate, but it soon became clear that the relocated nests, which were baking in the hot sun, resulted in the feminization of the largest part of the offspring. Based on research carried out by Tolen, the Sanctuary began relocating nests that were at risk to shadier portions of the beach.

While the success of the current program is still being measured, it appears that temperatures across Malaysia, like recent heatwaves, are only expected to increase, according to Chung Jing Xiang, a senior lecturer in marine science and environment at UMT. According to Chung, increasingly hot heatwaves are being prolonged and are more widespread across Malaysia due to the lasting effects of El Niño.

“Instead of bringing moisture to our region, it took our moisture and carried it to the Pacific Ocean. So when we have this reduced humidity, rain is less likely to occur and we will have fewer clouds in our sky. This will make us have a hotter and drier climate,” Chung told Reuters.

According to Chung’s research, at the current rate, the sea surface temperature over Malaysia has shown an increasing trend of about 0.2 degrees Celsius per decade since 1980. Analysts said the average surface temperature of the Malaysian Sea South China around Redang has been steadily rising towards 30 degrees Celsius in recent decades, and could eventually exceed the ideal incubation temperature range of between 28 and 30 degrees Celsius to ensure a balanced gender ratio.

After birth, researchers transfer the cubs to a small vivarium before releasing them at night to reduce their exposure to predators.

For decades, sea turtle populations have been declining drastically across Malaysia, often due to harvesting of their eggs, overfishing and lack of enforcement of conservation policies. Leatherback turtles used to be an attraction for visitors to the northern Malaysian state of Terengganu, with tens of thousands of females nesting on its beaches each year until the population collapsed in the late 1980s.