Modeling intraspecific genetic effects for management of aquaculture programs

Rapid worldwide development of marine finfish cage farming has raised awareness over the possible genetic and ecological effects of escaped fish on wild populations. With increased interest in implementation of marine aquaculture in the United States, NOAA Fisheries and other regulators charged with stewardship of marine ecosystems need tools to understand and mitigate risks presented by aquaculture escapees. To develop an understanding of genetic and ecological effects of escapes and design management strategies to address potential risks to marine resources, NOAA Fisheries has developed a numerical decision-support tool: the Off-shore Mariculture Escapes Genetics/Ecological Assessment (OMEGA) model. The OMEGA model is an extension of concepts from another model, the All-H Analyzer (AHA) that is used successfully in the U.S. Pacific Northwest to evaluate genetic and ecological interactions between hatchery and wild salmon and trout. OMEGA model input parameters include size and growth characteristics of cultured fish, frequency and magnitude of escape events, survival of escapees in the wild, probability of escapees encountering a conspecific natural population and interbreeding, and population dynamics of the natural population. Model results describe the influence of aquaculture escapees on spawning biomass, juvenile production, and genetic fitness of the composite population. Effects of interactions on fitness and abundance are based on the frequency and relative abundance of cultured fish that escape and survive to encounter a natural population, the difference in survival characteristics between the artificial and the natural environments, and the genetic legacy of the cultured and natural populations. NOAA Fisheries is using the OMEGA model to identify and evaluate risks of marine aquaculture operations, design sustainable aquaculture programs, explore the effects of regulation, and identify research priorities for areas of uncertainty. This talk will describe the model and present results for a hypothetical sablefish (Anoplopoma fimbria) culture program along the U.S. West Coast. We are interested in speaking with any and all individuals interested in collaborating on the further development of the model, applying the model to other species of interest such as rockfish (Sebastes spp.), yellowtail (Seriola quinqueradiata), salmon (Oncorhynchus spp.), or any other aquaculture candidate species, and to identify opportunities to validate model results.