Most of the world’s sea turtle populations are rebounding – even amid climate change threats

Most sea turtle populations are rebounding around the world, researchers said this week.

That promising news comes even amid continuing man-made threats to the beloved marine reptiles, including climate change, habitat loss, and fishing.

“Sea turtles are a shining light of marine conservation with recoveries of many nesting populations,” Graeme Hays, distinguished professor and chair in marine science at Australia’s Deakin University, said in a statement.

Hays and Deakin’s Jacques-Olivier Laloë, along with National Oceanic and Atmospheric Administration Fisheries researcher Jeffrey Seminoff, reviewed the status of the seven species of sea turtles around the world in a study published in the journal Nature Reviews Biodiversity.

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The reason for the rebound is tied to new protections and conservation efforts, with more turtles nesting at beaches that have stronger protections in place. Many fisheries have implemented measures to avoid catching the animals and removed or reduced artificial lighting that can confuse baby turtles trying to find the ocean.

“When I think of sea turtles, the first word that comes into my mind is resilience,” said Seminoff, a research scientist who specializes in sea turtles at NOAA Fisheries’ Southwest Fisheries Science Center. “They are sensitive because they depend on the marine ecosystem, but give them a chance to thrive and they will take advantage of it.”

Seminoff also said that the increasing number of sea turtles reflects a change in public mindset, with former poachers now leading visitors to nesting sites as a part of ecotourism.

In the past, commercial hunting, entanglement in fishing nets, and a loss of nesting beaches had resulted in declines. The Endangered Species Act and other measures helped protect the species more widely.

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Data on populations and nesting beaches show four of five regional populations of green sea turtles are increasing, NOAA said. That trend is the same for loggerhead turtles. Annual loggerheads increased from around 500 to 35,000 in Cape Verde in the North Atlantic Ocean.

There were also increases in individual populations of the critically endangered hawksbill and Kemp’s ridley, the vulnerable olive ridley, and flatback turtles.

Leatherback turtles, the largest of all sea turtles, were determined to be struggling the most. They are the only species that lack scales and a hard shell, and swim more than 10,000 miles a year to find prey in between nesting seasons.

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The researchers analyzed nearly 300 records of turtle numbers over time. They found that “significant population increases were three times more common than significant decreases. In an updated compilation of additional time series published in 2024, significant increases were six times more frequent than significant decreases.”

While the global evaluations reveal a “generally encouraging picture” of species growth, the researchers note that climate change resilience remains a concern.

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Rising temperatures at oceans and beaches lead to more female offsprin, and that could eventually interfere with reproduction. Yet, new evidence shows loggerheads are responding to the shifts, nesting in cooler areas. Turtles could also begin nesting at some beaches earlier in the year, the researchers said.

“The bottom line is: When you stop hunting and otherwise harming species and they regain their ecological foothold, they can again become a thriving part of the marine ecosystem,” Seminoff said. “There will always be surprises, but now many sea turtles have greater resilience going forward.”