R/E-24m

Strategic focus area:

Description:

Callinectes sapidus supports the most valuable commercial fishery in the Chesapeake Bay and its tributaries. Nationally, the average total dockside value of blue crab fisheries in Maryland, Virginia, North Carolina, Florida, Louisiana and Texas approaches $200 million. Interstate live blue crab transport has increased due to seasonal cycles of crab landings in the Chesapeake regions and changes in allocation of immigration permits for guest workers. The risk of spreading shellfish pathogens through commercial transportation of live seafood has drawn increasing attention, while the potential for blue crab pathogens to be spread by commerce may be underappreciated. In a comprehensive study of the genetics of the pathogenic blue crab virus, CsRV1, we recently discovered that a “Maryland” genotype is also common in crabs from Louisiana, indicating that interstate transport of blue crab may have moved the genotype from one region to the other. Thus far, at least nine viruses have been reported infecting blue crab, and recent developments in viral metagenomics will no doubt soon reveal even more viral diversity in blue crabs. Therefore, evaluating the potential for interstate blue crab imports to Maryland to introduce new crab viruses and novel genotypes of known viruses, is crucial for a more sustainable blue crab fishery in Maryland. We propose to apply metagenomic approaches to discover novel viruses in blue crabs from Maryland Chesapeake Bay and other states that have high exports of blue crabs to Maryland. This approach will help define the diversity of viruses in blue crabs and identify region-specific genetic differences of viruses that may have different pathogenicity to the host. The study will produce genetic information of novel viruses on which to develop assays to monitor prevalence and virulence of these viruses, then to evaluate risks of importing pathogenic viruses through interstate blue crab transports into the Chesapeake Bay.