Asian Tiger Shrimp Distribution and Genetics
Science Center Objects
The Asian tiger shrimp began appearing in commercial shrimp catches in 2006. They grow larger than native shrimp and are known to be fierce predators - so shrimpers and managers are concerned about the potential effects this species might have.
The Science Issue and Relevance: Beginning in 2006, a new non-native shrimp species began showing up in commercial shrimp catches – the Asian tiger shrimp (Penaeus monodon). The numbers caught each year have increased and in 2011 there was at least a 10 fold increase in the number observed. This species is very popular in aquaculture, but has not been farmed in the United States since 2005. The only known accidental release of Asian tiger shrimp occurred in 1988 off the coast of South Carolina. Individuals were captured from that release for approximately six months and then none were seen until one was captured in the Gulf of Mexico in 2006. Tiger shrimp grow much larger than native shrimp and are known to be predaceous. Shrimpers and managers are concerned about the potential effects this species might have. Although numbers have increased, we do not know if they are established or are waifs riding currents from other areas of the ocean. Escaped wild populations exist off western Africa and Venezuela. Escapes are believed to have also occurred in the Caribbean due to flooding resulting from tropical storms.
The Nonindigenous Aquatic Species database has been tracking reports of occurrence since the 1988 release. Starting in late 2011, NOAA developed a tissue repository to facilitate genetics work on this invasion. The genetics lab at the WARC began conducting genetics analysis early in 2012 to determine if the species is established and to try to identify the source of the population or individuals.
Methodology for Addressing the Issue: Genetic analyses will help to provide information on the founding population size, location, and source population(s) of P. monodon. Characterizing the genetic divergence of polymorphic loci will help to determine whether a reproducing population is present in U.S. waters. Additionally, the number of related or isolated populations throughout the Southeast will be addressed, providing information on larval dispersal mechanisms. This information, along with transport currents and other dispersal mechanisms will be used to help in forecasting future distribution patterns. When available, gut content samples will be analyzed using DNA barcoding primers to determine the taxonomic species or family of the prey items.
Future Steps: USGS scientists will collaborate with NOAA scientists to develop an Integrated Assessment for the Asian tiger shrimp. The NAS database program will continue to track occurrence records. Additional genetic markers will be developed to address Tiger shrimp population relatedness and connectivity.