The Influence of Fisheries on the Structure and Function of Aquatic Ecosystems

Abstract

Commercial and artisanal fisheries represent potent direct and indirect agents of stress within marine and freshwater ecosystems that structurally reshape the biological architecture, species composition, and biochemical cycles. In this integrative paper, we review the system-wide consequences of commercial and artisanal fisheries upon aquatic communities across the planet. Through analyses of food web trophic cascades, physical and biological community damage caused by invasive gear types and selective harvesting-related evolutionary effects from apex species loss, we analyze the processes of aquatic network disorganization. Bioregional data gathered globally reveal significant diminishment of system functional redundancy through heavy fishing, which makes aquatic networks exceptionally susceptible to disturbance events and the forces of exotic species invasion and climate change impacts. The modification of nutrient dynamics in benthic-pelagic coupling networks and nutrient regeneration cycles is then analyzed as a structural influence upon other aquatic service provision. Management actions associated with ecosystem-based management of fisheries, increased coverage of no-take MPAs, and appropriate technological modification of harvesting gear types are analyzed for effective restoration efforts and to ensure long-term resource sustainability. This review presents an organized framework upon which to direct future applied research and environmental policy direction within the aquatic sciences.