As commercial shrimpers in Louisiana battle unparalleled economic challenges that led to a strike this summer and a special state task force, reports are surfacing about catches including a non-native species that potentially could harm wild stocks in the Gulf of Mexico. Officials with the state Department of Wildlife and Fisheries say native shrimp species could be infected with a variety of diseases if giant tiger prawns, or penaeus monodon, somehow establish a population in Louisiana's waterways. Marine fisheries biologist Martin Bourgeois says his office has been fielding reports and collecting specimens. "So far, they've been taken in waters near Lafitte, Grand Isle and Venice," he says. "Several weeks ago, we had two documented captures a week apart in Vermilion Bay. All were mature adults." There also have been a "number of unconfirmed reports from shrimpers," Bourgeois added, and the department is circulating a new poster at shrimp docks in south Louisiana.
The species is native to the western Pacific and is widely harvested as food. They're visually striking, characterized by distinct dark and white bands, and are large: A giant tiger prawn could rest in a large hand and stretch from the wrist to fingertips, with its wide tail covering the area of two fingers or more. Giant tiger prawns have been reported in Louisiana as far back as the fall of 2007 and have been collected in South Carolina, Georgia, Florida, Alabama and North Carolina. According to the United States Geological Survey, some of the prawns escaped from a facility in Bluffton, S.C., in 1988. Approximately 1,000 adults were later recaptured as far south as Cape Canaveral, Fla.
The most significant threat to Louisiana's native shrimp is that giant tiger prawns carry several disease pathogens and various forms of bacterial, fungal and viral infections. If you should come across these non-native shrimp in local waterways, you are encouraged to save the specimen — put it on ice or refrigerate it — and record the location before contacting wildlife and fisheries at (225) 765-2641. — Jeremy Alford