Sea turtles face a daunting list of challenges — from beach debris to polluted oceans, poachers, trawl nets, fishing hooks and coastal development. Six of the world’s seven species qualify for some kind of endangered status. Now, a flurry of research has revealed a new threat: climate change. It’s already degrading key habitat, reducing the availability of nesting sites and hatch rates, shifting sea turtle ranges, and affecting their food sources.

Sea turtles are temperature sensitive at several stages. Nest temperature determines gender (warmer nests produce primarily females) and affects hatching rates; high temperatures can kill hatchlings. Around the globe, scientists are recording increased temperatures on important nesting beaches.

In the water, sea turtles can tolerate temperatures between roughly 59 and 95 degrees Fahrenheit. They become lethargic and can die in colder water, and are stressed by hotter water. Warmer-than-average ocean temperatures also affect sea-grass beds, the primary diet for green sea turtles and critical habitat for loggerhead prey, as well as coral reefs, which are important food sources for hawksbills.

More-frequent and harsher storms — a consequence of climate change — will increase beach erosion, washing away nesting areas or creating beaches too steep for turtles to negotiate. Rising sea levels will cover important nesting beaches. Studies in Mexico, Costa Rica and Barbados have predicted losses of 6 to 26 percent of nesting habitat, an already limited resource.

In the natural world, as the sea rises, the beach rises with it. But that can’t happen where permanent structures such as buildings or seawalls block such movement. Rising seas will likely prompt even more retaining structures as people try to keep the water at bay, which will further reduce available nesting sites. While turtles can and have adapted to the loss of nesting beach areas by moving to other beaches, they will eventually run out of suitable choices.

But all is not lost. Studies have found that shading or sprinkling nests with water can keep them cooler, and nests can be moved to protect them from flooding. Prohibiting construction near beaches and removing permanent structures such as sea walls would help ensure that as the sea rises, the beach can too. But most important will be addressing the causes of climate change.

“We need to take climate change into account in determining critical habitat and endangered status of sea turtles,” says Todd Steiner, executive director of Turtle Island Restoration Network. “The time for action is now.”

HOW TO HELP ...

HOW TO HELP

Around the world, 
a dedicated cadre of scientists and conservationists protects sea turtle habitat and nesting beaches every day. Many of these projects include eco-tourism components, and rely on volunteer support. Patrol for nests on remote beaches in Costa Rica with organizations such as Wider Caribbean Sea Turtle Conservation Network (WIDECAST) or safely shepherd hatchlings to the sea on a black-sand beach in Guatemala with Asociacion de Rescate y Conservacion de Vida Silvestre (ARCAS). If you have only a few hours, take a guided walk to watch nesting turtles in Florida, attend a hatchling release in Texas,
or tour sea turtle rehabilitation facilities in a half-dozen states and several foreign countries.

Find more than 80 project destinations around the world in A Worldwide Travel Guide
to Sea Turtles, to be released this month. The guide compiles information on responsible and sustainable projects, the organizations behind them,
and details about activities in the area.