Probing Molecular Determinants of Bivalve Resilience to Ocean Acidification (Regional)
(1) To identify molecular processes involved in bivalve resilience to ocean acidification and to characterize genetic markers associated with resilience
(2) To validate the ability of identified markers to predict resilience towards acidification
(3) To determine the physiological cost of resilience
We will use a complementary set of traditional breeding methods and modern high throughput genomic tools for the identification of molecular features associated with bivalve resilience to acidification. These comparative investigations will target 3 species with predominant regional importance for their economic and ecologic values: the eastern oyster (Crassostrea virginica), the northern quahog (Mercenaria mercenaria; a.k.a. hard clam) and the blue mussel (Mytilus edulis). Adult bivalves will be collected from several northeastern locations, spawned and larvae and juveniles raised under contrasting ecologically-relevant pH conditions. Bivalves will then be sampled at various developmental stages to assess molecular (high throughput sequencing) and physiological (scope for growth, immunity) responses to acidification and to determine the cost of resilience. In particular, we will identify molecular features (e.g. genetic variants such as single nucleotide polymorphism or SNP) and pathways linked to resilience by comparing molecular shifts in control and acidified conditions throughout development. Genetic variants that show consistent contrasts in frequency between "Winners" and "Losers" within each species will be identified and used to genotype the original breeders. Crosses of contrasting families (Winners vs. Losers) will then be produced and used for genetic markers validation. As in the past, we will use various means (factsheets, web, conferences attended by the industry, specialized journals) to ensure the widest distribution of study results to stakeholders and to the larger public. This will be facilitated by ongoing and new partnerships with the industry and with New York Sea Grant extension staff.
Bivalve molluscs represent the first marine resource in dockside value in several states, particularly along the east coast. While production traditionally relied on wild capture, bivalve aquaculture production in the last few decades has been displaying double digit annual growth. At the same time, hatchery production of seed, a main component of bivalve aquaculture growth, has been seriously hampered by ocean acidification in some of the major hatcheries in the nation. Worryingly, recent studies showed that the impact of current levels of coastal acidification on bivalve production in embayments along the east coasts is likely much more dramatic than initially thought. Nevertheless, the long-term effect of ocean acidification on these animals remains unpredictable, in part because of the strikingly limited information on intra- and inter-species susceptibility to acidification and on factors affecting species and individual resilience. "Winners" and "losers" exist within each species and between species and studies that comprehensively assess genetic determinants of resilience are lacking. The proposed research will fill this important gap and identify molecular markers and mechanisms associated with resilience to acidification in some of the most important bivalve species along the east coasts. This research has major implications for basic and applied science. It will determine molecular and physiological mechanisms and pathways involved in bivalve natural resilience to acidification and identify molecular features associated with resilience. This information is greatly needed for the management of wild fisheries and for the development of resilient varieties of aquacultured stocks. Resilient broodstocks will provide the industry with superior germline to face current and projected episodes of acidification in local waters.