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bioRxiv · 10.1101/2020.08.03.233981

Marine reserve benefits and recreational fishing yields: the winners and the losers

Abstract

Marine reserves constitute effective tools for preserving fish stocks and associated human benefits. However, not all reserves perform equally, and predicting the response of marine communities to management actions in the long run is challenging. Our decadal-scale survey of recreational fishing yields at Frances 45-year old Cerbere-Banyuls marine reserve indicated significant protection benefits, with 40-50% higher fishing yields per unit effort in the partial-protection zone of the reserve (where fishing is permitted but at a lower level) than in surrounding non-reserve areas. Over the period 2005-2014, catch per unit effort (CPUE) showed a similar pattern of decline inside and outside the reserve while weight per unit effort (WPUE) increased by 131% inside and decreased by 60% outside. Different CPUE and WPUE trajectories among fish families indicated changing catch assemblages, with yields increasing for the family most valued by fisheries, Sparidae (the ecological winners). However, reserve benefits were restricted to off-shore fishermen (the social winners), as on-shore yields were [~]4 times lower and declining, even inside the reserve. Our study illustrates how surveys of recreational fishing yields can help evaluate the effectiveness of marine protected areas for key social and ecological protagonists. We show that, more than four decades after its establishment, fishing efficiencies at the historical Cerbere-Banyuls marine reserve are still changing, but benefits in terms of catch abundance, weight, and composition remain predominantly restricted to off-shore fishermen. Further regulations appear necessary to guarantee that conservation strategies equitably benefit societal groups.

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Kayal, M., Cigala, M., Cambra, E., Soulat, N., Mercader, M., Lebras, A., Ivanoff, P., Sebesi, L., Lassus-Debat, A., Hartmann, V., Bradtke, M., Lenfant, P., Jabouin, C., Dubreuil, J., Pelletier, D., Joguet, M., Le Mellionnec, S., Brichet, M., Binche, J.-L., Payrot, J., Saragoni, G., Crechriou, R., Verdoit-Jarraya, M.. 2020-08-03. Marine reserve benefits and recreational fishing yields: the winners and the losers. https://doi.org/10.1101/2020.08.03.233981

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