SAN JUAN, Puerto Rico (AP) — The world's largest turtle species built a record number of nests along Puerto Rico's lush coastline this year and 68,000 baby turtles have hatched, government officials said Thursday.

The announcement comes eight months after the federally endangered leatherback turtle began nesting along the U.S. territory's coastline, considered one of the top U.S. nesting sites for that species. The 1,390 nests reported this year is the highest number in recent history, according to Carlos Diez, turtle project coordinator for the Department of Natural Resources.

He attributed the increase in part to new conservation efforts launched this year, including cordoning off nests, and more volunteers monitoring beaches.

But Diez noted that only one out 1,000 leatherback turtles survive to become an adult.

"It's too low," Diez said. "We have a lot more to do."

Natural resources officials said that turtles for the first time were favoring new nesting sites instead of traditional locations such as the sister island of Culebra and the northeast coast, which became a protected area earlier this year.

"It's something we're investigating," Diez said.

The most popular spots this year were beaches in the northern town of Dorado and the southeastern town of Maunabo, with more than 630 nests alone reported there.

As a result, the Department of Natural Resources is pushing to designate those beaches as possible natural reserves or refuges to prohibit deforestation and coastal development and help keep Puerto Rico as a top turtle destination.

"Puerto Rico has the highest number of leatherback turtles in the U.S. and is second in the Caribbean after Trinidad and Tobago," said Carmen Guerrero, natural resources secretary.

The turtles arrive to nest every two years, coming as far away as Canada and northern Europe. They can weigh up to 2,000 pounds (900 kilograms) and can measure up to 7 feet (2 meters) long. An estimated 26,000 to 43,000 female turtles nest annually across the world, down from some 115,000 in 1980.