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 could potentially harm wild stocks in the Gulf of Mexico. Officials with the state Department of Wildlife and Fisheries say native shrimp species could be inflicted 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 actually collecting specimens. “So far, they’ve been taken in waters near Lafitte, Grand Isle and Venice,” Bourgeois says. “Several weeks ago we had two documented captures a week apart in Vermilion Bay. All were mature adults.” There have also been a “number of unconfirmed reports from shrimpers,” he adds, and the department is circulating a new poster at shrimp docks in south Louisiana.
The species is native to the western Pacific and are widely-harvested as food. They’re likewise visually striking, characterized by their distinct dark and white bands. It’s quite large as well; a Giant Tiger Prawns could easily rest in a large hand and stretch from wrist to fingertips, its wide tail covering the area of two fingers or more.
Giant Tiger Prawns have been reported in Louisiana as far back as fall 2007 and there have also been species collected in South Carolina, Georgia, Florida, Alabama and North Carolina. According to the United States Geological Survey, an agency within the Interior Department, the prawns were introduced locally because they escaped from various aquaculture facilities.
Giant Tiger Prawns were inadvertently set loose from a facility in Bluffton, South Carolina in 1988. Approximately 1,000 adults were later recaptured as far south as Cape Canaveral, Florida. It’s also speculated that an individual prawn captured off Alabama’s coast recently may have escaped with others from another, nearby aquaculture facility during hurricanes Katrina and Rita in 2005.
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 — ice or refrigerate — and record the location before contacting the Louisiana Department of Wildlife and Fisheries at 225-765-2641.
