Sustainable fisheries: Towards operationalization of decision making accounting for biodiversity

Abstract

Overexploitation of biotic resources constitutes a major threat on marine biodiversity while demand for seafood will rise in the next decades. Application of Life Cycle Assessment to marine ecosystems needs further focus. This study applies two existing methods (Langlois et al., 2014 and Emanuelsson et al., 2014) of fishing impact assessment on biodiversity to 125 common fish stocks fished in the 14 marine areas drawn by FAO and proposes operational guidelines for sustainable production and efficient conservation policies. We show that unsustainable fishing is responsible for a loss of up to 30 times the potential yield of major fish stocks such as Atlantic cod, red snapper and bluefin tuna. We identify depleted fish stocks for which biomass is up to 15 times lower than it should be (yellownose skate fished in South America) and stocks facing fishing mortality up to 1.9 × 107 times higher than required to allow sustainable recovery (Pacific Ocean perch fished on the US West Coast). Regarding intrinsic biodiversity, our study shows that we are not able to understand the consequences of overfishing through a cause-effect chain due to lack of science knowledge. However, we display how to limit the impacts on biodiversity by using complementary indicators at species and ecosystem level. The complexity of marine ecosystems and the remaining limits of studied methods are discussed, showing the compelling need for further data collection and analysis, and opening ways for targeted research.