Aquaculture of native shellfish can impact nearby ecological systems and wild conspecifics by creating opportunities for genetic impacts on native populations. If wild populations are genetically adapted to local environmental conditions, interbreeding with cultured conspecifics from other locales may disrupt patterns of local adaptation, potentially jeopardizing wild populations by decreasing their adaptive potential. On the other hand, the addition of genetically diverse cultured organisms may enhance genetically depauperate populations. This enhancement is likely to occur in populations where genetic discontinuities exist as a result of population fragmentation from anthropogenic disturbances, rather than naturally occurring restrictions to gene flow.
A significant impediment to sustainable aquaculture is the lack of proper information to predict the impacts of culturing native shellfish species for restoration and commercial production. As a result, expansion and growth of domestic aquaculture is constrained and may be halted by management directives that restrict distribution of hatchery derived native shellfish until the potential interactions are better understood.
Our approach is to simultaneously address local adaptation in three genetically differentiated populations of Olympia oysters by evaluating genotype-by-environment interactions. We will reciprocally transplant seed produced from wild parents collected from contrasting environments into all environments. This very large reciprocal transplant experiment can test for a home field advantage in survival, maturation and growth in Olympia oysters. The overall goals of this project are to increase our knowledge of local adaptation in Olympia oysters to address concerns that interbreeding between potentially maladapted cultured and wild stocks could negatively impact wild populations. Accordingly, in order to attain these goals, the specific objectives of this proposal are to 1) Evaluate fitness components and performance of seed from different origins in a reciprocal transplant experiment and 2) Characterize genetic and epigenetic markers associated with oysters from different origins in a reciprocal transplant experiment.
This research effort is funded by: