The shrimp supply is shrinking.
Billions of the shellfish in Southeast Asia have died of early mortality syndrome since the disease, which is now in plague-like proportions, surfaced in 2009.
Now farmers and fishermen in Thailand, the largest supplier of shrimp to the U.S., told Bloomberg News that they expect exports to decline as much as 50 percent in 2013. The plague, which has also afflicted shrimp populations in China, Malaysia and Vietnam, has driven the price of shrimp in the U.S. 20 percent in recent months, according to the Wall Street Journal.
Seafood restaurants are now awaiting further price hikes.
Darden Chief Financial Officer Brad Richmond, whose company owns the chain eateries Red Lobster and Olive Garden, said seafood makes up a quarter of total goods sold.
"Shrimp is our highest-volume protein," he said in a recent earnings call, according to Bloomberg Businessweek.
He said he doesn't expect the menu prices to increase just yet.
Landry's, which owns Bubba Gump Shrimp and McCormick & Schmick's, says it "may selectively raise prices" as it buys shrimp from farms in Indonesia, India and Latin America.
The plague killing the juvenile shrimp -- the giant tiger prawn and the whiteleg, which are two commonly raised species -- destroys an organ used in its digestion process.