BIOMIMICRY CONSIDERATIONS FOR SEAWEED MARICULTURE: ASSESSING FUNCTIONAL DIVERSITY AT THE LOCAL SCALE  

Increasingly, aquaculture research explores synergistic interactions between cultivated species, with a classic example being the development of integrated multi-trophic aquaculture (IMTA) farming systems that co-culture fish, shellfish, and seaweeds. Seaweeds, or marine macroalgae, have gained prominence as a foundational element of most modern IMTA systems because of their capacity to mitigate negative environmental impacts associated with farming fish and other higher trophic level species. Yet, for more than 50 years, monoculture of seaweeds on par with land-based industrial agriculture has been undertaken in Asia. With the development of novel seaweed-based products and emergence of new markets for nutritious and environmentally-benign sea vegetables, global demand for seaweed crops is escalating. Seaweed cultivation is thus occurring along new coastlines and thereby creating opportunities to explore innovative approaches to farming and the development of best management practices. In locations where seaweed aquaculture operations have already scaled up to high levels of commercial production as well as in emerging industries, issues have been noted in relation to disease and biofouling. Are these concerns endemic to seaweed aquaculture or do they stem from the monoculture mindset that has characterized the sector's growth thus far?

The research presented draws upon literature from several fields and investigates the potential for co-cultivation of multiple seaweed species, either for improved design of seaweed-only farms or as a component of IMTA systems. This study builds on the observation that healthy natural marine ecosystems are typically characterized by mixed algal communities wherein various species of seaweeds grow in close proximity, often intertwined with consistent patterns and epiphytic relationships. As an initial step in examining such interactions and possible interdependencies, data were collected to assess minimum estimates of seaweed biodiversity at a local scale (1m sq.) within the broad groups of reds, greens, and browns. Local-scale seaweed diversity measurements are reported for both tropical and temperate bioregions, including archipelagos on Panama's Caribbean coast and in Canada's Bay of Fundy. In both areas, prior research programs have evaluated broad-scale distribution of seaweed species. Results from this initial assessment and related work may inform design of polyculture systems to mimic natural biodiversity configurations.