Beyond the bay: Biophysical simulations of disease dispersal suggest broadening spatial scales for aquaculture carrying capacity

One major societal challenge is meeting the constantly increasing demand for (sea)food in a sustainable way. Marine aquaculture offers large production potential, but it is crucial to define production limits that maintain ocean health. The concept of aquaculture carrying capacity (CC) provides such limits for locally defined areas. However, the ocean is subject to large- and small-scale dynamics, and far-reaching effects of aquaculture (e.g., the spread of marine diseases with ocean currents) are currently neglected in CC estimates. Here we predict potential "impact areas" with a biophysical simulation approach and find them to be larger than those currently considered in CC estimates. We suggest "impact areas" as a measure for spatial connectivity with the requirement to define what is an acceptable "impact area" case specifically. The proposed approach is applicable to various marine aquaculture systems and would drive CC estimates toward improved sustainability by considering the impact and risk of dispersal beyond the immediately adjacent area.