MOUNT PLEASANT - Tommy Edwards rocked on a floating platform in Shem Creek. He kept one hand on the hull of his shrimp boat for balance as he daubed white paint with the other, sprucing up Mrs. Judy Too for the Blessing of the Fleet and Seafood Festival.

On Thursday, federal shrimping waters open three miles out, the start to an uncertain spring season that follows three straight years of poor catches. The more productive near-shore state waters aren't likely to open for another month, if then.

Early signs for the spring crop aren't particularly encouraging. The late cold has slowed the crop.

"We have seen decent numbers. Not good numbers. But decent numbers. Mostly small," said S.C. Department of Natural Resources wildlife biologist Larry DeLancey. Researchers on an unrelated trawl, though, did find a few big shrimp, he said.

Edwards is coming off a winter when his patched-up boat, Mrs. Judy Too, began sinking at dock, costing him thousands in repairs. The leak is fixed, but no, he didn't think the boat would be ready to go by May 1, he said. He might run out to federal waters when he does get it prepped, but he's not chomping at the bit. Shrimp tend to be more scattered in those waters. The price of fuel is rising again.

Edwards is watching the near-shore state waters. "The water temperature gets to 73 degrees, the shrimp are going to do what they're going to do." That's when he expects the state waters to open.

That's no given. Only a few years ago after a cold winter and spring, DNR delayed the opening well into June to give the depleted crop a chance to recover.

DNR biologists plan to trawl Charleston Harbor in the coming week and then ride with a shrimper on a sample offshore, DeLancey said. "We'll just have to see where the weather goes from here."

The Mrs. Judy Too is among maybe a half dozen shrimp boats remaining of a fleet that once tied off rail to rail three deep at the Shem Creek docks. It was another bad winter for them. Wando Shrimp Co. shut down after more than a half century. Shrimper Rocky Magwood's Lady Eva sank at the dock a few weeks before Edwards' boat and was later lost at sea under tow.

Last year's fall catch was down 30 to 40 percent because of heavy flushing rains. The crop suffered from black gill disease, which isn't harmful but is unsightly to humans and weakens the shrimp.

After a good start in 2012, the total catch was only about half of what it had been the year before. And those years followed the 2010-11 cold that led to the late June opening.

The captains and their boats are aging out. Shrimper after shrimper is giving up the trade, driven out by catch difficulties, higher costs and wholesale prices that haven't kept up. Few younger shrimpers take over. About 400 boats are licensed in South Carolina today, a fourth of the number at the industry's peak in the 1980s. Some years, far fewer than that number even bother to cast the nets. They can barely pay for fuel, much less maintenance to keep their boats in the water.

But the business is in their blood. Rocky Magwood was out on that recent afternoon working on the Winds of Fortune, the boat he's taking over for his uncle, Wayne Magwood. It was tied off to Edwards' boat. He and Edwards railed about DNR for not leaving the season opening to the shrimpers' discretion, like Georgia or Florida.

"Open it and let it be," Magwood and Edwards said.

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