Don’t miss the big fish! Operational accounting of two major drivers of marine biodiversity loss in LCA of seafood products

Impact of fishing activities on marine biodiversity lacks important impact pathways in Life cycle Assessment. We develop Biomaris, a novel LCA-based way of accounting for multifunctionality of fisheries through the “fishnet approach” that includes various species in the fishnet and allocates impacts between co-products at landing. Biomaris adds two important LCIA pathways: resource depletion and seabed impact and uses the ecosystem quality endpoint of LC Impact. Impact pathways are grouped to display impacts for 4 drivers of biodiversity loss: direct exploitation, land and sea-use change, climate change, and pollution. It is applied to a business case study of a fishery of saithe (Pollachius virens) with bottom trawling. Case study at landing shows that impact on seabed is substantial (1×10−9PDF.year/kgliveweight), and that resource depletion and climate change are of similar order of magnitude (2×10−14PDF.year/kgliveweight), the pollution driver being less important. Case study also displays impact of processed product at distribution (Climate change impact: 6×10−14PDF.year/kgnetweight). As of now, despite drivers being expressed in the same unit (PDF.yr), aggregating them is not advised, as, depending on driver, unit concretely represent different level of species disappearance, either (eco)regional or global. There are still important missing impact pathways to comprehensively assess impacts on biodiversity of seafood products (e.g., ghost fishing, plastic pollution, …), but Biomaris displays practical guidance to account, to our knowledge, for the most up-to-date science in the LCA domain. •Biomaris, a biodiversity assessment framework for fished seafood products, is proposed.•LCIA is completed with impact pathways resource depletion and seabed impact.•Method is tested on a practical business case study accounting for bycatch.•Resource depletion and seabed impact are relevant issues to be accounted for.•Aggregation of these added impacts pathways with the others is discussed.