The crabs had a tough life. Captured for a lab experiment, they were now returning to the seas one by one, split in half for shark bait.

Bonnethead shark

One of more than 40 shark species native to South Carolina waters.

The smallest of the hammerhead sharks.

Eat crabs, shrimp, small fish; found along coral reefs and shallow coastal waters.

Are not a threatened species and are considered abundant.

Source: New England Aquarium

But when you want bonnethead sharks for an exhibit at the South Carolina Aquarium, it’s either pay $4,000 each or play out a line in Charleston Harbor, where they thrive. Acquisition for an aquarium isn’t all it’s cracked up to be; it’s less. It is, in fact, fishing.

Nigel Bowers, exhibit fabricator, and his volunteer crew member each know just how tough it is to crank up the twin-motored Scout, slip out from underneath the aquarium facility and skip away into the brine.

“It was beautiful. It was a perfect day,” said Josh Zalabak, who crewed Friday. “It’s a great opportunity. You get paid to go fishing, and shark fishing at that.”

But it’s high-pressure work; these acquisitions are time-sensitive. As the waters cool over the next few weeks, the bonnetheads will move out of the shallows into deeper water where they’ll be much harder to catch.

And for the second time in a week, the aquarium’s acquisition crew came back without one. Asked about the pressure, Bowers sighed.

“We just have to get back out next week,” he said.

The purpose of stocking bonnetheads is so hush-hush the crew won’t talk about it yet. But we know: The bonnetheads will be among a number of native shark species in a spring exhibit called Shark Shallows.

Although Friday’s catch was a sandbar shark that was released and a big horseshoe crab, there will be bonnetheads, promised Kate Ditloff, of the aquarium.

The job is so much pressure the aquarium’s husbandry team jostle to take turns for it. That leaves Bowers with an odd assortment of talent. Zalabak, “the alligator guy,” is a herpetologist. On Wednesday, the crew was horticulturist Kristen Colvin. It was make or break for Colvin, after two unsuccessful tries for a shark. She worked two rods at a time, cleaved through crab after crab and came up empty. The disappointment was visceral. Colvin shrugged, giggled a little and grinned.

“The only things I’ve caught are spartina (reeds) and sea pansies,” she said.

But what can you expect from a horticulturist?

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