Leatherback sea turtles could be gone in 20 years.
A new study published in the Ecological Society of America’s journal Ecosphere finds that the leatherback, the largest sea turtle in the world, is dying off rapidly.
A team of researchers from University of Alabama at Birmingham studied leatherback nests at Jamursba Medi Beach in Papua Barat, Indonesia, where 75 percent of the turtles lay their eggs. The number of leatherbacks nesting there decreased to only 1,532 in 2011, a huge decline from a peak of 14,455 in 1984.
“If the decline continues, within 20 years it will be difficult if not impossible for the leatherback to avoid extinction,” Thane Wibbels, professor of reproductive biology at the University of Alabama at Birmingham and a researcher in the study, told Science Daily. “That means the number of turtles would be so low that the species could not make a comeback.”
Leatherback turtles have an enormous range, and individuals can migrate more than 7,000 miles across the Pacific Ocean, making regulations protecting them difficult to enforce, as 20 countries govern the area they inhabit.
“It is extremely difficult to comprehensively enforce fishing regulations throughout the Pacific,” said Ricardo Tapilatu, the team’s lead scientist, Fulbright Scholar and biology doctoral student at UAB. The turtles themselves are very hardy creatures, growing as large as six feet long and weighing 2,000 pounds, and are able to dive to depths of 4,000 feet.
While conducting the research, the team was excited to discover thousands of previously unknown nests only a few kilometers from known nesting sites, but soon found that these nests were also disappearing rapidly.
“We were optimistic for this population when year-round nesting was discovered in Wermon Beach,” said Pete Dutton, Ph.D., paper co-author and head of the NOAA Southwest Fisheries Science Center’s Marine Turtle Genetics Program. “But we now have found out that nesting on that beach appears to be declining at a similar rate as Jamursba Medi.”
There are four major threats facing the turtles, according to the study: non-native beach predators, such as pigs and dogs, eating the eggs; increased sand temperatures that kill eggs or prevent males from hatching; fisherman catching the turtles while migrating across the ocean and locals harvesting eggs and adult turtles for food.
“The leatherback is one of the most intriguing animals in nature,” said Wibbels. “And we are watching it head towards extinction in front of our eyes.”