Not quite two weeks ago, on June 5, Sal Sunseri opened the first New Orleans Oyster Festival. Postponed a few years because of Hurricane Katrina, the affair, in the city’s French Quarter, included contests for wine and oyster pairings as well as oyster shucking — basically, cracking open the shell to expose the slippery gray meat for slurping. On June 10, however, the Sunseri family business, P&J Oyster Co., which in 134 years had become the chief oyster purveyor to some of the city’s most esteemed restaurants, effectively closed. Not only was it running short of the delicacies, but people were afraid to eat them. “We’re mourning,” Sunseri says.