On a chilly winter afternoon, veteran marine biologist Bob Prescott looks across shimmering Cape Cod Bay, reflecting on his 40-year crusade to preserve one of Earth’s most resilient creatures. “Turtles have been around longer than dinosaurs,” he says. “They survived the asteroid that crashed into the Yucatán that killed the dinosaurs 86 million years ago. It’s probably because they were still buried in the ground. When they came up, it was dark and cold, but they could live.”
And yet today, these ancient inhabitants of tropical waters are in peril. Climate change, as well as industrial and agricultural runoff, is conspiring to overheat our oceans, setting a cold-water trap for vulnerable turtles who have followed warming currents too far north. “When it happens every year, it’s not an accident,” says Prescott.
The warm, north-flowing Florida Gulf Stream is teeming with dolphins and sharks, tuna, billfish and wahoo—large predators that feed on hundreds of other species, all riding the swift current. It is a rich marine food chain. Among the passengers on the route is the ocean’s smallest and most endangered turtle, the Kemp’s ridley. Like large sea turtles, such as Greens, Loggerheads, and Leatherbacks, which are also threatened, the Kemp’s ridleys are navigating a dangerous new world, an ever-expanding highway of freakishly warm water up the East coast. Of all species, they migrate farthest north during hatching season.
As a 30-year resident of South Florida, I’ve had the pleasure of watching the great sea turtles slowly crawl out of the crashing Atlantic surf in the dead of night, ever so slowly pulling themselves up onto our beaches. Their size is daunting. Adult Loggerheads can weigh up to 500 pounds. Giant Leatherbacks, the largest of all marine turtles, can weigh up to 2000 pounds and measure six feet in length. Tiny Kemp’s ridleys measure just around two feet in length and can weigh up to 100 pounds.
Once several yards up on the beach, quietly and with great labor, females use their hind flippers to dig a two to three–foot hole, then lay up to 100 eggs. It can take several hours before a turtle redeposits the sand to safely cover the vulnerable eggs. If the nest is not compromised, it will take around 60 days for hatchlings to scratch their way to the surface and waddle into the waves, guided by the moonlight.
As moving as it is to watch these huge, beautiful creatures disappear back into the breaking tide, their job done, the scurrying hatchlings, no bigger than golf balls, are utterly mesmerizing. Joy is mixed with trepidation as babies scramble into the surf before birds, crabs, entanglement in plastic, or dehydration cut their lives short. It’s estimated that only one in a thousand hatchlings will make it to adulthood.
Once back in the water, turtles must contend with a host of new challenges, now more heightened than ever. Ocean waters have cyclically warmed then cooled over millennia, but never at this pace. “Now we’re getting into the uncharted territory of what happens, because climate has always changed, but never this rapidly,” Prescott explains. “Turtles have been here for tens of millions of years, so they’ve seen all of this before. But it’s been slower.” In Cape Cod Bay, for example, the water is five degrees warmer than it was in 2000.
The result is what Prescott calls “cold-stunned” turtles. Fooled into thinking they’re safely in warm water, they become listless and depleted when autumn rolls around and temperatures rapidly drop. Marine biologists are now confronting the terrible sight of thousands of turtles, predominantly the smaller Kemp’s ridleys, comatose and dying along the beaches of the Northeast.
Circumstances are so alarming that awareness has transcended the somewhat insular world of marine biology and entered a new stage: that of cause célebre for the Hollywood elite. Through his Leonardo Dicaprio Foundation, which supports global environmental causes, in 2021 the actor led a $43 million pledge to support preservation in the Galápogos Islands, home to giant tortoises. The actress Kate Mara has lent her voice to Oceana. Mark Ruffalo previously won an award handed out by the Turtle Conservancy, an organization founded by the hotelier, filmmaker, and conservationist Eric Goode. The gala was attended by Sarah Silverman, Drew Barrymore, Edward Norton, and Rashida Jones, to name a few, and held at the trendy Bowery Hotel in New York. Prior to that, Richard Branson and Paul McCartney publicly disagreed over a sea turtle breeding farm in the Cayman Islands. The list goes on. But while celebrity names raise awareness, the trenches in the battle to save the planet’s most endangered turtles are in the waters of New England, and on the sandy beaches of the South.
In Florida, it is not just the rising temperature of the ocean water that’s cause for concern. It’s the heat of the sand. Marine researchers and veterinarians say 90 to 95 percent of turtles that hatch on the Southern coast are now female. A turtle’s sex is determined by the temperature of the sand where the eggs are laid. Cool sand produces males. Like the water, the sand in Florida is gradually getting hotter. In Juno Beach, the giant sea turtles that lay their eggs on the beach are showing signs of “feminization.” Not only does this include Loggerheads, but also Leatherbacks and Green turtles.
“The easy quote is ‘Hot chicks, cool dudes,’” says Sarah Hirsch, a senior manager of research and data at the nearby Loggerhead Marine Life Facility. As sand temperatures rise, the concern is that one day there won’t be enough male hatchlings to re-populate the next generation. “If you have prolonged periods of time when those eggs are exposed to above 33 degrees Celsius, we start to see increases in abnormalities when the hatchlings come out of their eggs.”
As the long winter closes in on Wellfleet, Massachusetts, the number of stranded Kemp’s ridley turtles has picked up at an alarming pace. Most are two to five years old, born in the Gulf of Mexico and Padre Island, Texas. The “cold-stunned” turtles have inadvertently migrated into a frigid oblivion, as a recent winter cold snap pushed the ocean temperature below 50 degrees Fahrenheit. Jenette Kerr, a marketing and communications coordinator at the Massachusetts Audubon Society, works alongside marine scientists and volunteers during the cold months, combing Cape Cod’s shores for turtles in need of resuscitation. “It’s an annual mortality event,” Kerr says. “There’s no other event like it in the world. And it’s every year. Why wouldn’t we rescue them when they are so endangered, and there’s such a high success rate of rehabbing them?”
Back in the Audubon Society lab, which is soundproofed to further protect the traumatized turtles, biologists attempt to slowly warm each turtle out of a life-threatening, hypothermic sleep before delicately transferring them to the New England Aquarium or the Loggerhead Marinelife Center. There, they will be monitored and ultimately released back into warm water.
But why are these ancient, rugged ocean survivors not genetically wired to return to the safety of the warm waters from which they came? Birds, for instance, experience what’s scientifically known as the “photoperiod”: As the days get shorter, it triggers a migratory urge. Physiologically, they prepare; they feed; they get nervous. “Sea turtles are not like that,” Prescott says. “They are up here, and don’t know they have to get out. They’re in warm water; there’s plenty to eat; where are they going?” Every week it gets colder, and then by 65 degrees Fahrenheit, they’re in slow motion. Unfortunately, they have company.
Tens of thousands of foot-long, cold-stunned needle-nosed Atlantic Saury, as well as sunfish, have also washed ashore on Cape Cod in recent months.
Still, Prescott believes there is hope. He says turtles have been pushed to the edge of extinction before, only to be saved by mankind. By the 1970s, there were significantly fewer turtles in the water. The Kemp’s ridley population had dropped dramatically from 40,000 to 500, due to being hunted for food and killed by shrimp boats. Florida’s Green turtles weren’t seen on the beaches. Only a few Loggerheads were spotted in very isolated places.
In 1973, Richard Nixon signed the Endangered Species Act, the world’s first comprehensive legislation designed to protect species from extinction as a “consequence of economic growth and development untempered by adequate concern and conservation.” The act served two main goals: to save species from extinction, and to recover populations so they no longer needed the law’s protection. As a result, conservation became a serious national conversation, and awareness grew. It continues today. On the southeast coast of Florida, where 90 percent of Loggerheads nest, volunteers have launched a campaign against the harmful effects of light pollution. Towns along the coast have been swapping yellow or white streetlights for amber and purple, a friendlier light frequency, when turtles nest. (Female sea turtles seek out dark beaches to deposit their eggs; artificial lights confuse them and deter many from coming ashore.) Prescott is adamant: “If it weren’t for Florida, and the protecting of the nests, we wouldn’t have Loggerheads.”
Still, with the rapid acceleration of climate change, the numbers for certain species of sea turtles continues to dwindle. The World Wildlife Fund now says that human activity has “tipped the scale against the survival of these ancient mariners,” noting that three of the seven existing species—leatherback, hawksbill, and Kemp’s ridley—are now critically endangered. Which begs the question: are turtles one of the canaries in the coal mine? “Absolutely,” Prescott says. “They are one of many species. You can look at certain birds as an indicator. But certainly turtles.”
Short of a global environmental effort to stop or slow ocean warming, Kemp’s ridleys may be driven to extinction. There is a temporary remedy: Take a certain number of nests, bring them into the lab, incubate them at a cooler temperature, and produce males. “It’s within our ability to save them if we really needed to,” Prescott says. “But it needs to be studied more.”
There is theoretical agreement at the Loggerhead facility, but there is also concern that the data being collected on the health of the turtles is being outpaced by the rapidly warming ocean. “It’s difficult because these animals live for decades, and they don’t sexually mature until they are 20 to 25 years old,” Hirsch says. “If you have 25 years of data, that’s just one generation.”
The path forward is surely daunting, but possible. Prescott, a lifelong resident on the Cape, looks across the bay as another cold snap blows in from the West. Gliding below the surface are these rugged Archelosauria, members of the dinosaur family, close relatives of birds and crocodiles, majestic creatures of the sea. “The asteroids couldn’t kill them,” he says. “But we’re going to, if we don’t do something.”
This story and more appears in PALMER Volume 3, available now.
