Leatherbacks aren’t only spectacular for bodies that rival grand pianos in size and weight, but also for their temperature tolerances. By taking refuge in cool upwellings, they can inhabit tropical waters up to 86°F; on the flip side, by warming their bodies with activity and insulating fat, they can tolerate waters as cold as 32°F. But even leatherbacks have their limits.
A recent study in the journal Chelonian Conservation and Biology found that warming oceans are shifting the nesting sites of leatherback sea turtles (Dermochelys coriacea) to cooler waters. Typically, the critically endangered population of eastern Pacific leatherbacks concentrates its nesting along the west coasts of Mexico and Costa Rica. Now, though, they’re showing up about 1,000 miles south in Ecuador.
Read more: “How Sea Turtles Find Their Way”
“Historically, observing female Eastern Pacific leatherbacks on Ecuador’s beaches was a rare or unusual event, but our findings suggest they are adapting their reproductive cycle to thrive and survive in coastal Ecuador,” explained lead study author Juan José Alava, a biologist at Simon Fraser University in Canada.
Alava and coauthors in Ecuador compiled records of leatherback nesting activity along Ecuador’s coast from as far back as 1980. Their compilation included peer-reviewed studies as well as conservation reports, government survey records, and validated social media sightings. They also tracked the El Niño and El Niña events that sway sea surface temperatures.
They found record-breaking numbers of nesting females, with the uptick starting around the year 2000. Hatchling leatherback turtles hadn’t been reported along Ecuador’s coast since 1983. So, the emergence of nests in the winters of 2020 and 2021 in Manabí Province was a cause for celebration. And both 2025 and 2026 saw additional hatching success of nests that were relocated to protected areas.
“It signals new hope for a subspecies of leatherback on track for extinction in the eastern Pacific within 60 years,” added Alava.
Unfortunately, though, a higher frequency of leatherback strandings has also been observed of late. From 2011 to 2026, at least 35 dead leatherbacks were confirmed to have beached on the Ecuadorian coast. Many of those strandings were associated with injuries from fisheries and other human activities.
And so, Pacific leatherbacks haven’t quite found safe harbor yet.
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