A 141-pound loggerhead turtle just underwent X-rays in the medical lab. A Bermuda chub fish lies on the cold metal slab of the forensics lab, about to be necropsied.

Under the idle operating table in the surgery room, a diamondback terrapin has burrowed into mulch in a box, about to lay eggs.

The patients get their treatment while workers in hard hats are putting on the last electrical outlet covers, installing electronics in the interactive sea turtle triage display and checking the pipes that will feed more than 13,000 gallons of water to seven sea turtle tanks.

The South Carolina Aquarium's marquee Zucker Family Sea Turtle Recovery exhibit is moving toward its public opening Memorial Day weekend, complete with iPad stations featuring life-size replicas of the four species found in South Carolina where visitors can perform their own virtual diagnoses.

This is a centerpiece of the aquarium's evolution from an exhibit facility to a conservation advocate. The nonprofit's shift comes as public attitudes about wildlife and captive animals change.

Shift in focus

The $5.3 million expansion is one of those necessary upgrades and gambles as the aquarium in Charleston battles leveling-off attendance. It's no coincidence that admission fees will rise by $5, to $29.95 for adults, on May 27 when it opens.

Today, keeping wild animals captive is criticized as inhumane and facilities struggle to maintain an audience while people flock to rescue and sanctuary efforts. Zoos and aquariums are becoming more about habitat, using captive animals to educate about species and the threats they face.

Reintroduction to the wild is the sought-after ideal. That has been the goal — and the draw — of the aquarium's sea turtle rescue effort from its beginning.

The aquarium also has launched education efforts on wildlife environmental issues such as sea rise and plastics. But the Recovery exhibit is designed to make the focus on the care and restoration of the cherished, threatened, native species of the Lowcountry, as well as other marine creatures.

Fittingly, visitors enter the new exhibit from the viewing area of the two-story Great Ocean Tank, the aquarium's previous marquee.

The heart of the expansion is the Sea Turtle Care Center, the medical facility seen through viewing windows from the public area. Visitors can watch recovering turtles in their tanks, as well as surgery or other medical procedures underway. The wired rooms allow the procedure to be explained live and live-streamed.

Senior veterinarian Shane Boylan can't quite keep the smile off his face as he points to the research storage freezer for animal samples that drops to an ideal 80 degrees below zero. Or at the CT scan facility that means staff no longer will have to truck sick or injured animals offsite.

"We started off in a closet with no equipment. Our medicine has expanded to where it's on a par with anywhere else," he said.

Critical to mission

Into that closet in 2000 — the year the aquarium opened — state wildlife biologists brought a loggerhead sea turtle for rarely attempted surgery in a last-ditch attempt that saved it. Treating or rehabilitating sick sea turtles was not in the aquarium's original plans. Little thought had been given to doing any more than exhibiting them.

But something remarkable was happening. Fledgling volunteer groups watching over beach sea turtle nesting began to draw onlookers and more volunteers. Crowds grew each time the aquarium sea turtle rescue team and S.C. Department of Natural Resources biologists released a rehabbed turtle back to the sea.

The loggerhead gradually became a beloved ambassador of the coast, rivaling the shrimp boat with its splayed nets. As turtle after turtle was returned to sea — more than a few near-hopeless cases — the makeshift basement recovery operation began getting notice.

A few improvised tours of the operation became a sought-after once-a-day tour ticket despite the extra charge and grew to attract 20,000 people per year.

Now the works will be on display to all of the aquarium's 450,000 visitors per year, including recent turtle releases shown on a multi-screen video display at the exit.

The expansion comes as loggerhead turtles appear to be rebounding from a long-term decline in nest numbers. A record 6,444 nests were laid in the coastal dunes in 2016, continuing an up trend in recent years.

Meanwhile, the aquarium's rescue is treating record numbers of sick or injured turtles. More than 220 sea turtles have now been rehabbed and released — loggerheads, greens, Kemps ridley and the huge leatherbacks. Kevin Mills, aquarium chief executive officer, has called the effort a critical aspect of the facility's mission.

The medical center started operating as soon as the first equipment arrived in 2011, with turtles brought up from the basement, while the rest of the exhibit was still in planning. Now the site includes touches such as an "endless pool" exercise tank where turtles can actively swim against the flow, to better prep them for release.

The heart of the work, though, might be the McNair Center for Sea Turtle Conservation and Research, paid for party with a $500,000 grant.

Boylan, who used to call on a small group of researchers to pull from an even smaller body of veterinary knowledge about various marine creatures, is now in position to continually supplement that knowledge with records and studies. Researchers, in other words, will now call on the center.

Kelly Thorvalson, the longtime sea turtle recovery manager and now the conservation program manager, walks through the facility shaking her head in amazement at the before and after.

"From the first kiddie pool in the basement to be sitting at the board room table designing this and then to see that come to fruition," she said. "I've never been part of anything like this."

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