Using a trait-based framework to characterize farmed seaweeds and guide selection of new candidates

Abstract Seaweed aquaculture could meet the “triple bottom line” of environmental, social, and economic sustainability. However, while seaweeds in nature are incredibly diverse, only eight species are responsible for >95% of production, leaving untapped potential. We use a trait-based framework to identify candidate seaweed species for commercial production. We apply a trait-based approach to characterize the traits of species already successfully aquacultured (identified from Food and Agriculture Organization production data) and compare them to a global species database of seaweeds with traits related to performance. We collected traits from the literature for the aquacultured species that were not already in the global dataset. The trait distributions of aquacultured and non-aquacultured species did not differ, underscoring the significant biological potential for expansion into production of novel seaweeds. We found five broad “types” of seaweeds farmed at scale and posit the trait combinations distinct to each group could facilitate selection of candidates for aquaculture production. Our approach and analyses indicate the current practices in seaweed aquaculture do not take full advantage of the huge diversity of seaweed in the ocean. Indeed, there is likely significant capacity to diversify production and unlock seaweed aquaculture potential to create a vibrant and sustainable industry.