We are investigating the cause and potential impacts of the recent tenfold increase in invasive Asian tiger shrimp sightings along the southeastern U.S. coast and Gulf of Mexico. Our research is the first study comparing the DNA of specimens collected from the Gulf area with that of Atlantic coast specimens to determine origin and other possible differences. It is providing managers and fisherman the first-available biological and ecological assessments related to the Asian tiger shrimp.
Why We Care
Asian tiger shrimp (Penaeus monodon) sightings along the U.S. southeastern coast and Gulf of Mexico increased tenfold from 2010 to 2011. Jumbo prawns are cannibalistic, and, because of their size, they can eat many of their smaller Gulf cousins and their larvae. As with all nonnative species, there are concerns that tiger shrimp may transmit disease to and compete with native stocks. Fishermen and scientists want to know where the shrimp came from, whether they are here to stay, and how they will impact the ecosystem and native shrimp fisheries.
What We Are Finding
Invasive tiger shrimp grow faster and larger than native shrimp, with individuals reaching more than 13 inches long and weighing up to a 1/4 pound. Females lay from 50,000 to 1,000,000 eggs in the coastal ocean, numbers comparable to native shrimp. Tiger shrimp eggs hatch within 24 hours, and the larva migrate into estuaries, where they mature into juveniles and small adults before they return to the ocean to spawn.
Tiger shrimp are being captured—largely in shrimp trawls—in estuaries and the coastal ocean from North Carolina to Texas. Most are collected in the late summer. Their preferred depth ranges from 0 to 110 meters, primarily in sandy or muddy bottoms. We do not think Asian tiger shrimp are established in United States waters.
What We Are Doing
Our study area extends from North Carolina to the Caribbean and Gulf of Mexico. We are assessing the status of the Asian tiger shrimp invasion and its potential impacts, including:
- Biology and ecology
- Outreach and education.
We are looking for possible triggers for the recent increase in sightings. While there are no known Asian tiger shrimp farms in the United States, they may have escaped from an aquaculture facility/ies. Other speculated pathways include ballast water from ships or ocean currents from established populations in the Caribbean or even Gambia, Africa. We are also investigating the developmental stage of the tiger shrimp to determine if they are breeding in U.S. waters or are being carried here by currents.
We will continue to monitor the Asian tiger shrimp invasion and further develop biological assessments. If the invasion intensifies, ecological assessments will be needed to forecast additional impacts of this new species in estuaries and the coastal ocean along the U.S. southeastern coast and Gulf of Mexico.