Critically endangered leatherback sea turtles in the Pacific Ocean could become extinct within 20 years if the population of the species continues to decline, according to a new study.

An international team led by the University of Alabama at Birmingham (UAB) has documented a significant 78 percent decline between 1984 and 2011 in the nests of the Pacific leatherback turtles at Jamursba Medi Beach in Papua Barat, Indonesia.

This beach is the turtle's last stronghold in the Pacific Ocean, and it accounts for 75 percent of the total leatherback turtles in the western Pacific. The turtles, which were estimated to be around 14,455 in 1985, have fallen to a low of 1,532 in 2011. "If the decline continues, within 20 years it will be difficult if not impossible for the leatherback to avoid extinction," Thane Wibbels, a professor of reproductive biology at UAB, said in a statement. "That means the number of turtles would be so low that the species could not make a comeback."

"The leatherback is one of the most intriguing animals in nature, and we are watching it head towards extinction in front of our eyes," added Wibbels.

Leatherback turtles are the largest of all turtles. They can grow up to six feet long and weigh as much as 2,000 pounds. They have the ability to dive in depths of nearly 4,000 feet and can also make trans-Pacific migrations from Indonesia to the U.S. Pacific coast and back again.

This has raised concerns among scientists, as the turtles face the risk of being caught and killed in fisheries. Since the turtles can migrate more than 7,000 miles and travel through the territory of at least 20 countries, it has become difficult to enforce stringent fishing regulations throughout the Pacific, said the researchers.

Based on extensive surveys and research work since 2005, Wibbels and his colleagues have identified four major problems that the leatherback turtles face - nesting beach predators, such as pigs and dogs, that were introduced to the island and eat the turtle eggs; increase in sand temperatures that can either kill the eggs or prevent the production of male hatchlings; being caught and killed in fisheries during migration; and harvesting of adults and eggs for food by islanders.

Researchers insist on taking better conservation efforts to protect the turtles. Researcher Ricardo Tapilatu, a Ph.D. student and Fulbright Scholar in UAB, has been studying leatherback turtles and is working on their conservation program since 2004.

He has worked with the locals in Indonesia to educate them and limit the harvesting of adults and eggs. He is also designing ways to improve the survival rates of the eggs and increase hatchling production by reducing their exposure to predators and hot temperatures, using an extensive beach program.

"If we relocate the nests from the warmest portion of the beach to our egg hatcheries, and build shades for nests in other warm areas, then we will increase hatching success to 80 percent or more," said Tapilatu.

The details of the findings are published in the journal Ecosphere.