Climate change could lead to thousands of turtle strandings on Cape

Staff members at the Florida Keys-based Turtle Hospital looked at a group of cold-stunned Kemp's ridley sea turtles in December. The turtles were rescued between late November and early December off Cape Cod. Larry Benvenuti/Florida Keys News Bureau/AFP

As climate change progresses and the Gulf of Maine warms up, more Kemp’s ridley turtles will head to that region in the summer — and get caught in cold water off Massachusetts as they try to return to their winter haunts in the Gulf of Mexico, researchers warn.

“With much warmer waters in the Gulf of Maine every year, migrating turtles get caught by geography — the long arm of Cape Cod — which cuts off their route to the south,” UMass Amherst conservation biologist Lucas Griffin, the first author of the study, said in a statement.

Researchers said that, with the Gulf of Maine expected to continue warming at a rapid rate in coming decades, the findings were “particularly alarming.”

The study, which also involved researchers from Mass Audubon and the University of Rhode Island, was published Tuesday in the journal PLOS One.

Hundreds of Kemp’s ridleys are cold-stunned in Cape Cod Bay each year. More than 1,100 were cold-stunned in 2014 before they could make their annual fall migration to the Gulf of Mexico, researchers said.

A cold-stunned Kemp's ridley sea turtle attempted to climb out of its tub at the Turtle Hospital in Marathon, Fla.Larry Benvenuti/Florida Keys News Bureau/AFP

Prior to 2009, there were only two years when the number of cold-stunned turtles was above 100. Now that number is rare, researchers said.

Griffin said researchers found a connection between years that the Gulf of Maine was warmest and the number of cold-stunnings of turtles heading south.

“We demonstrate higher cold-stunning years occur when the Gulf of Maine has warmer sea surface temperatures in late October through early November,” the study said.

“Our predictions follow the observed trend and predict there may be as many as 2,349 Kemp’s ridley turtles cold-stunned annually in Cape Cod Bay by 2031,” he said.

Cold-stunned turtles can be rescued, but the process is labor-intensive and expensive.

“Climate change may present the broadest threat among many to sea turtle conservation, but not enough is understood about its potential effects on sea turtle cold-stunning events,” Griffin said.

The study recommended “continuing efforts to rehabilitate cold-stunned individuals to maintain population resiliency for this critically endangered species in the face of a changing climate and continuing anthropogenic threats.”

“As we continue to observe warming [sea surface temperatures] in the northeast U.S. driven by climate change, managers need to be prepared for increasing numbers of Kemp’s ridley cold-stun strandings to occur,” the study said.