Abstract
Bay scallops (Argopecten irradians) once supported a successful wild fishery that collapsed in the 1980's due to habitat loss and overfishing. Restoration and aquaculture efforts have been underway since the early 2000's to replace the lost economic value and ecological benefits of this system. Mud blister worms (Polydora spp.) and pea crabs (Pinnotheres maculatus) are two macroparasites that threaten the success bay scallop aquaculture and restoration efforts. The coastal environments which bay scallops, pea crabs, and mud blister worms inhabit are experiencing earlier seasonal increases in water temperature and longer periods of seasonal warmth. Earlier seasonal warming of coastal waters is expected to extend reproduction periods for pea crab and mud blister worms, increasing population density and risk of infection for bay scallops. The aims of this thesis were to 1) document the role of water temperature on the infection dynamics of mud blister worms and pea crabs in aquacultured bay scallops and their impacts on bay scallop fitness, 2) determine the role of water temperature on the infection success of adult pea crabs, 3) identify potential pea crab and mud blister worm mitigation strategies for bay scallop aquaculture. Work from this study shows that natural infection prevalence of mud blister worms in aquacultured bay scallops is linked to increases in water temperature and pea crabs and mud blister worms negatively impact the reproductive health of bay scallops. In addition, this research indicates that pea crab infection success significantly varies depending on the sex of infecting pea crab and infection success significantly increases with increasing water temperature. Finally, this work was able to determine that the location of aquaculture gear in the water column effectively mitigates pea crab and mud blister worm prevalence in aquacultured bay scallops.