Bulldozers and Climate Change Threaten Leatherback Turtles


Leatherback turtle. Photo: Ken Clifton / CC BY-NC 2.0

Onlookers watched in shock on July 9 as thousands of leatherback turtle eggs were crushed by bulldozers on a beach in Trinidad. The incident happened after a botched effort by government work crews to redirect the Grand Riviere, a river which threatened to erode the land near a hotel were guests planned to watch the annual leatherback turtle hatching.

Instead of the seeing new life of a critically endangered species emerge, guests watched as dogs and birds scavenged what was left of the estimated 20,000 destroyed eggs.

A sea turtle the largest in the world—it can reach seven feet long and weigh more than a ton—the leatherback can live 100 years or more. Despite a 1970 listing under the Endangered Species Act, the species continues to decline amid fishery threats, habitat destruction and, according to a recent Nature Climate Change study, climate change.

The study investigated how warming affects the leatherback turtle, and its prognosis was grim. Higher temperatures, it showed, equated to fewer baby leatherback turtles, partially due to food loss (cooler sea-surface and air temperatures mean higher productivity for phytoplankton and zooplankton, which means more for sea turtles to eat). The study also found that turtles that nested later in the season (when higher temperatures prevail) faced increased probability of nest collapse due to dry sand. Cooler temperatures, in contrast, result in wetter conditions and healthier nest sites. These factors point to a possible population decline of 75% by the year 2100 if warming trends continue.

In a Responding to Climate Change article, James Spotila, co-author of the Nature Climate Change paper, said for populations to recover successfully, “the challenge is to produce as many good hatchlings as possible. That requires us to be hands-on and manipulate the beach to make sure that happens.”

This could entail creating shaded areas to help keep the beach cool. Some countries are starting to protect beaches, and environmental groups are keeping a vigilant watch on nesting sites to guard against poaching. Guarding against climate change, though, will be a harder task altogether.