SPATIAL PLANNING FOR OFFSHORE AQUACULTURE IN THE SOUTHERN CALIFORNIA BIGHT:  BALANCING MULTIPLE OBJECTIVES TO ACHIEVE SUSTAINABLE DEVELOPMENT AND ECOSYSTEM HEALTH  

Offshore aquaculture is an emerging industry with the potential to contribute significantly to global seafood production and food security.  However, interactions between marine aquaculture and the surrounding ecosystem have raised concerns about the effect of aquaculture development on environmental health and on other ocean resources.  Further, there are a wide variety of farm types and aquaculture species that each have distinct environmental requirements for optimal growth, spatially variable costs, and pose quite different concerns in terms of environmental impact and interactions with other uses.  Thus, it is important to strategically and simultaneously plan for different types of aquaculture across the seascape in order to most effectively maximize aquaculture value while minimizing conflicts.  We address this problem and demonstrate the value of multi-objective planning with a case study that integrates bioeconomic modeling with tradeoff analysis to inform spatial planning for offshore shellfish, finfish, and kelp aquaculture in Southern California.  While this area is currently home to only a small marine aquaculture industry, it has been targeted as a region with high aquaculture potential, making it an excellent case study for pro-active planning.  We considered how the surrounding environmental conditions coupled with the type and location of farms would impact marine benthic habitat, risk of disease outbreak between farms, yields from wild capture fisheries, coastal viewshed, and the economic value of the aquaculture industry.  Results indicate that this type of modeling can significantly improve the profitability of the aquaculture industry and reduce conflicts and impacts expected under conventional planning.  For example, 28% of potential mussel farm sites overlap with wild-capture halibut fishery grounds, yet strategic planning can enable mussel aquaculture to develop extensively in the region without any effect on the value of the halibut fishery.  This study demonstrates the value of bio-economic modeling and multi-objective planning for addressing multiple environmental and economic objectives in the context of marine aquaculture development.