Another “record” year is well underway for sea turtle nesting on the South Carolina coast. Yet nearly half those nests are on a single island left unsupervised: Cape Island in the shut down federal Cape Romain National Wildlife Refuge.

“No work is being conducted on the refuge with the exception of law enforcement,” said Raye Nilius, S.C. Lowcountry Refuges Complex project leader.

The nests, though, ought to be OK, said wildlife biologist Michelle Pate, of the S.C. Department of Natural Resources, who works with the turtle program. Cape Island is the turtle hatchery for U.S. Fish and Wildlife Service on the refuge. The nests that have not yet hatched are in wire mesh cages to protect them from predators like raccoons — work that service biologists did before the federal shutdown.

“There’s no real concern for Cape Island right at the moment,” Pate said.

The banner year for the state follows the previous “record” year in 2012 and continues what is now a six-year trend of nest numbers having spiked and remaining relatively high.

It’s one more indication that the corner has been turned for the endangered sea turtle species. It just might be that these “new” arrivals are grown-ups of hatchlings that began emerging in the 1970s, after sea turtle excluder devices and other protections were put into place.

Cape Island is ground zero for the 40-year effort to restore the loggerhead and other declining turtle species in the state and region. Year-in and year-out, the six-mile-long strip of sand holds more than 1,000 sea turtle nests — one-third of all the sea turtle nests from North Carolina to Georgia.

As for the turnaround, biologists remain cautious, if optimistic, because more nests than ever are spotted and watched with the growth of volunteer turtle watch groups. The biologists pay closer attention to the “index beaches,” six of the densest nesting spots along the coast, where data has been recorded consistently since 1982 and the increases are spottier.

Since the turtles were put on the federal endangered species list in the 1970s, the numbers of Atlantic nesting turtles generally were thought to be in severe decline in Florida, where the overwhelming bulk of nests are laid, and a more gradual decline in South Carolina, where the most nests outside Florida are laid. The states are the two largest-by-numbers nesting grounds in the world for loggerhead turtles, which lay the overwhelming bulk of the nests.

In 1988, South Carolina became the first state to mandate turtle excluder devices on shrimp boats.

Reach Bo Petersen at 937-5744, @bopete on twitter or Bo Petersen Reporting on Facebook.