Drexel professor coordinates map of endangered sea turtle migration

Leatherback sea turtles are the giants of the turtle family, growing to more than 6 feet long and sometimes living longer than a century. With just thousands left in the world, they’re critically endangered.

A Drexel University professor has assembled an international research team to track their migration patterns across the whole Pacific for the first time.

Environmental science professor James Spotila convinced researchers from New York to Indonesia to pool data from satellite-linked tracking devices from different studies to create the first Pacific-wide map of migration patterns. The look at 135 turtles confirmed what researchers had suspected — that commercial fishing operations are likely contributing to the population decrease.

“There were hints from the individual studies that the way the turtles were behaving could affect their interaction with fishing activities,” Spotila said. “But when you compile all their data together it becomes very clear that the turtles are feeding the same place the fishermen are fishing.”

Spotila said the next step is using that data to shape public policy.

“The turtles are hanging on by their flipper-tips,” Spotila said. “So we need to get this fishing thing under control.”

The beach in Costa Rica where Spotila does research has 31 nesting females now, down from a thousand in 1990.

The population of leatherback turtles in the Eastern Pacific Ocean has dropped by more than 90 percent in the past few decades.

The new analysis found the migration patterns of turtles in the Western Pacific varied, but those in the Eastern part of the ocean clustered together for feeding.

“We’re most concerned about the Eastern Pacific population,” said Helen Bailey, an assistant professor at the University of Maryland Center for Environmental Studies and author of the study. “They’re going to be most vulnerable to any threats, for example from fishing or to any change in their food supply” that might result from climate change.