The series

This is part of an occasional series looking at how the coast and the ocean off the Lowcountry are changing, and what it means for a region where people have made a life and a living for generations in tune with the sea.

WADMALAW ISLAND — The yacht is a custom-built sport-fishing boat, 66 feet long, with twin screws kicking out 1,980 horsepower.

The three sea turtles were just out of rehab, looking for a ride back home. They got picked up by a Texan.

El Tejano, or The Texan, was the boat that carried Kemp’s ridley, green and loggerhead sea turtles out to sea Friday. It’s owned by South Carolina Aquarium volunteer John Hill of Wadmalaw Island.

He’s the 70-year-old co-founder of a leading global energy investment company, with more than $23 billion in raised capital, according to Thomas Reuters. Hill’s First Reserve Corp. buys companies in everything from oil to windmills. He won’t retire because “it’s just too much fun,” he said.

Born and bred in Texas, he’s a tournament sports angler, a regular top finisher in the Governor’s Cup, the premiere sportfishing series in South Carolina.

In other words, Hill might not be what you first think of when someone says “wildlife conservationist.” He is passionate about it, and the reasons might surprise.

He grew up hunting and fishing and was taught early on to respect the animal, take only what you eat. He’s practiced that all his life.

In the 1980s, he and Marilynn, his wife, moved to the Lowcountry. He’s the sportsman; she’s the historian. They fell in love with the place.

He began fishing offshore and got a wake-up call: The species he was after were disappearing, one by one, to overfishing.

The manager in him took over.

“I really got thinking, we’ve got to solve this problem. This is one area I know. I can make a difference,” he said.

Among other efforts, he goes out yearly to take part in a blue marlin tagging project off North Carolina, trying to get a better read on the huge, beautiful and tasty game fish that conservationists worried will be fished to extinction.

Hill is a gregarious, soft-spoken man in horn-rimmed glasses. On the turtle release day, he wears a S.C. Aquarium logo ball cap and deck shoes without socks.

One of the guests calls El Tejano a chariot, but Hill isn’t out to showcase his boat. He leaps to help handle and load a shipping crate with the 150-pound loggerhead inside and is one of the people who lift it from the crate to release.

As El Tejano enters the North Edisto River on its return, he grabs a hose to wash the salt from a videographer’s tripod.

For Hill, as for the others on board, “the main focus is getting these animals back to the wild,” as National Aquarium husbandry aide Amber White said.

Each of the seven sea turtle species is considered endangered or threatened. Hunted for food or eggs, struck by boats, hung in nets, they appear to have been in a long decline, and they have been on the federal list for a generation.

With nesting protection and other conservation efforts like the one led by the S.C. Department of Natural Resources, biologists think the loggerhead at least might be turning the corner on recovery.

That’s due in no small part to an army of not-so-usual volunteers like Hill.

He “was hooked” on turtles from his first visit to the rehabilitation program at the aquarium. If you’re an out-of-town guest of Marilynn’s and his, you will visit it too.

Turtles are hardy, yet vulnerable, he said. That appeals to him.

“She’s ready to fly!” Hill calls out when the green turtle lifts its nose to the salt air and flaps its flippers as it’s released.

He doesn’t like golf. All his life, he wanted the Spencer Yachts convertible he now owns. He calls it his “last boat,” to Marilynn’s amusement, but his love for it shines as he surveys the cockpit.

Sea turtles must be released in a specific range of temperatures, and Hill has run the boat as far as the Gulf Stream, 60 miles offshore, to help the aquarium with a release.

They couldn’t do it without him.

On Friday, El Tejano’s fuel bill ran $4 per gallon and “we’ll burn through some fuel today,” Hill promised.

The smile is self-effacing when he is asked about giving the cause that big a hand. The equity manager has been asked before. He knows what the answer sounds like.

“Sad as it is to say, I really believe in what they’re doing,” he said. “I want to support what they’re doing.”

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