Mariculture is a growing industry in Alaskan communities that can complement commercial fishing as an economic driver. The coastal zone of the Gulf of Alaska (GOA) has many locations that are likely suitable for mariculture growth; however, the expansive size of the GOA shoreline, variability of the coastal systems, and lack of in-situ nearshore oceanographic data make it difficult to predict successful oyster farming locations. To support industry development, we need localized approaches to farm site selection based on environmental factors influencing crop production. Oceanographic conditions affect growth duration, crop health, and economic output for the farmer.
Through the Mariculture Research and Restoration Consortium (MarRecon), we analyzed oceanographic variability at eight kelp and oyster farms across three Gulf of Alaska regions: Kodiak, Kachemak Bay, and Prince William Sound. In-situ sensors located on partner farm sites collected hourly measurements of salinity, temperature, dissolved oxygen, turbidity, and chlorophyll fluorescence. Using principal component analysis (PCA), ANOVA of PCA variance, and analysis of similarities (ANOSIM), we found that Kachemak Bay and Kodiak consistently grouped together, while Prince William Sound separated distinctly. Higher temperatures and lower salinities drove this separation year-round, with other variables contributing seasonally. Multivariate analyses indicated seasonal oceanographic variability across sites within regions.
Our results provide insight into environmental drivers of productivity at these farms to inform future farm siting decisions and provide partner and prospective farmers with environmental data at farm sites across the Gulf of Alaska.