Oyster lovers will shell out more for the marine delicacy this fall, as freshwater runoff from Hurricane Harvey's historic floods killed virtually all of the bivalves in the prolific seabeds of Galveston Bay.

The storm was the latest setback to a multimillion-dollar commercial fishing and seafood-processing industry that appeared poised to finally rebound from floods, including two devastating tropical weather systems, and an extended drought in less than a decade. Shrimpers, crabbers and other fishermen who work the bay also will feel an impact.

But it's most lethal in the case of the oysters, as Harvey-spawned rains and rainwater runoff drove down the bay's salinity to fatal levels. Salinity levels of 12 to 30 parts per thousand are ideal for a healthy oyster harvest in Galveston Bay, which researchers say is the nation's most bountiful. Yet preliminary tests performed by commercial fishers on Tuesday revealed salinity levels at 0 to 5 parts per thousand - and excessive water continues to drain into the bay.

Industry leaders fear no more than 10 percent of oysters in the bay prior to the storm have survived. It's possible, they said, that the entire crop is lost.

"That much freshwater in the bay has taken its toll on us," said Mark Lewis, sales representative for wholesaler, Jeri's Seafood. "There's nothing in Texas to buy."

Wholesale and retail prices already have risen by 15 to 20 percent, according to one estimate. Given the expected length of the recovery and the added expense of shipping in oysters from other parts of the country, further price spikes are expected.

Customers at Tommy's restaurant and oyster bar in Clear Lake will soon say goodbye to the days of paying $6 for a dozen on the half-shell. Owner Tom Tollet said he sells about 10,000 oysters that way each week, most of them from the Gulf. He's not sure how much longer he can hold out before he has to raise prices.

"This is a devastating blow to the Galveston Bay oyster supply," Tollet said. "And we're all going to feel it."

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Commercial fishing and seafood processing in the bay generates an estimated $66 million in direct personal income and $111 million in direct business revenue, a 2017 study by Martin Associates found.

The freshwater deluge threatens much of that enterprise, as shrimp and crab normally found close to the shoreline fled in search of saltier water farther into the Gulf - and largely out of reach of smaller, independent fishermen who now have to deal with damaged boats and equipment as they ponder whether they can or should to invest in Gulf fishing licenses.

Oysters, immobile creatures, had no means of escaping Harvey's torrents, and the industry built around their harvesting is paying for it. At a meeting this week with state officials, Jeri's Seafood brought in buckets of dead oysters for display.

The Texas Department of State Health Services closed the bay to commercial harvesting, in accordance with tropical storm protocol, on Aug. 26, a day after Harvey made landfall near Rockport. The agency expects weeks of testing before it reopens the bay.

Then it will take two years or longer for oysters to repopulate the bay, said Lance Robinson, deputy director of the Texas Parks and Wildlife coastal fisheries division.

The 2017 oyster harvesting season, which opens to the public on Nov. 1, was poised to show how well Galveston Bay recovered from a series of devastating natural phenomena.

Prior to Hurricane Ike in 2008, the bay accounted for 80 percent of the state's oyster harvest, Robinson explained. But after Ike dumped nearly 2 feet of sediment, effectively smothering half of all the oyster reefs, the bay produced only a third of the state's product.

"Ike was a game changer," Robinson said.

As the bay's oyster population recovered, other Gulf states rushed in seeking seafood untouched by the Deepwater Horizon oil spill that devastated their fisheries in 2010.

Then a nearly 5-year drought raised salinity in Galveston Bay to dangerous levels, attracting bacteria, disease and natural oyster predators.

Freshwater runoff from Houston's Memorial Day and Tax Day floods of 2015 and 2016, respectively, proved a further setback.

But by this May, state and private sustainability efforts seemed to pay off with the bay's crop at last reaching numbers akin to those in the pre-Ike days.

In the course of four days, Harvey undid it all. Fishermen and wholesalers are alarmed not only over the dangerously low salinity levels in the bay, but also over how Harvey's freshwater runoff managed to hit the entire bay in one go.

"I've never seen mortality that widespread," said Tracy Woody, general manager at Jeri's Seafood.

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The primary alternative for businesses like Jeri's and the local Prestige Oysters Inc. is to head to Louisiana's waters.

Yet even that recourse will be limited. Louisiana officials already had determined that public oyster harvesting grounds contain the lowest recorded stock size of any season.

Steve Beck, oyster program manager for the Louisiana Department of Wildlife and Fisheries, noted that some privately leased harvesting areas maintain high productivity, but others are still in recovery mode after a series of ecological changes and the 2010 oil spill took their toll on the crop.

The state agency faces the challenge of balancing immediate business interests with the need to preserve as many oysters for future seasons.

That challenge looms larger in the wake of Harvey.

"We were concerned that effects of Hurricane Harvey would bring Texas ships our way," Beck said.