At Pappadeaux Seafood Kitchen in Austin, the Gulf Coast oysters on the half shell would typically come from Texas this time of year.
Instead, the restaurant is getting them from out of state, manager Onika Reyes said, because of a reddish-brown algae bloom known as red tide that has shut down oyster harvesting along the entire Texas coast.
The red tide flourished in part because of Texas' historic drought conditions and has left dead fish littered along beaches. It has also released a toxin into the air that makes people cough and wheeze. The toxin, which builds up in oyster meat, has devastated the state's oyster harvest, which was worth $19 million in 2010.
"It's horrible," said Clifford Hillman, whose Dickinson, Texas-based company, Hillman's Shrimp & Oyster Co., processes oysters. "I've never seen it like this, ever."
With half the season remaining, state officials and industry leaders have yet to calculate the economic toll.
There are signs of improvement. The Texas Department of State Health Services on Friday opened two areas - Espiritu Santo Bay and a piece of San Antonio Bay - to oyster harvesting. That marked the first time any part of the Texas coast opened during the current oyster harvest season, which normally runs from November 1 to April 30.
Red tide thrives in salty water. Recent rains have helped bring more freshwater into Texas bays that, because of the drought, had a high salt content. Last year was the driest year on record in Texas and the second-hottest.
"I'm pretty confident saying the red tide is on its way out for good," said Meridith Byrd, a marine biologist at the Texas Parks and Wildlife Department. "It's been dealt its death blow by the rain and the cold."
Even after a red tide is gone, oysters may continue to test positive for the toxin for awhile, so the health department is continuing to check oyster meat.
"It still could be some time before the entire coast is open," state health department spokesman Chris Van Deusen said.
The algae's toxins can gather in oyster tissue - and in that of clams, mussels and whelks. People who eat them can get neurotoxic shellfish poisoning, which causes nausea, dizziness, and tingling in the hands and feet.
Fish, shrimp and crabs caught alive are safe to eat because the parts people eat don't absorb the toxins, according to the health department.
Red tides come along in Texas every few years - including in 2009 - but Hillman, 61, a third-generation oyster businessman, said this season is different.
"This is unprecedented in that it consumed the whole coast all at one time and has lingered," he said. "Typically, if one bay is closed, you can source your product from another bay. Our situation this year is dire in that the whole coast has been closed for so long."
The red tide affects a broad range of businesses connected to the oyster industry, from fuel suppliers and marine hardware stores to grocery stores and restaurants.
It's killed at least 4.4 million fish in Texas, Byrd said.
Beach-goers can suffer throat and eye irritation, taking take a toll on tourism.
"Undoubtedly there was some effect" on tourism, South Padre Island Mayor Robert Pinkerton said, thankful that is struck during the slow season between late September and early December. "Fortunately, it's not here when we're really booked: spring or summer."