Seaweed farming offers a zero-input production system with multiple benefits including CO₂ absorption, biodiversity enhancement, healthy food production and sustainable coastal communities. Despite the rapid expansion of seaweed farming, a major factor limiting the productivity of seaweed aquaculture in the mesotrophic waters of the North Atlantic, is the proliferation of biofouling organisms on the seaweed blades. This unwanted growth results in increased processing costs, decreased product value and risks for public health. Target biofouling species include invertebrates and algae, which settle from the plankton as larvae or spores respectively. Despite the obvious challenges, solutions are possible by carefully planning the harvesting time, location/depth and species of the farmed seaweed. In this study, data were collected during a full production cycle from a Scottish seaweed farm.  Epibionts (including meroplanktonic zooplankton and epiphytic algae) were monitored from their early life stages by combining microscopy (zooplankton, phytoplankton and epibionts from the blades) and molecular approaches (environmental DNA metabarcoding and epibionts barcoding). Succession patterns of epibionts were observed during the studied period and lags were identified as well as variation in the intensity of biofouling by depth. This information can be paramount for predicting, preventing, and mitigating biofouling in seaweed aquaculture to safeguard the economic viability of the industry.

Primary Presenter: Sofie Spatharis, University of Glasgow (sofie.spatharis@glasgow.ac.uk)

Authors:

Martin Llewellyn, University of Glasgow  (martin.llewellyn@glasgow.ac.uk)

Eleni Christoforou, University of Glasgow  (eleni.c.chr@gmail.com)

Kyla Orr, KelpCrofting  (info@kelpcrofting.com)

María Algueró-Muñiz, University of Glasgow  (maria.alguero-muniz@glasgow.ac.uk)