Assessing fishing impacts in a tropical reservoir through an ecosystem modeling approach

22 pages, 8 figures, 2 tables, supplementary material https://doi.org/10.1007/s11160-018-9539-9Ecological models are useful for evaluating fishery management scenarios, as they allow researchers to investigate alternative fishing effort, as well as varying environmental and trophic interaction scenarios. Through an ecosystem modeling approach (Ecopath with Ecosim), we addressed the possible impacts of small-scale fisheries on the structure and functioning of a tropical ecosystem (Itaipu Reservoir, Brazil). We found that fishing effects and predator–prey interactions were the main drivers explaining catch trends in the Itaipu Reservoir fisheries. The mean trophic level of catch did not change throughout the analyzed time period and no losses in secondary production from exploitation (L index) were observed, indicating that Itaipu fisheries are sustainable regarding ecosystem effects. The negative impacts of introduced species on native species seem to be greater than the fishing impacts. Fishing simulations from the ecosystem Maximum Sustainable Yield (MSY) reduced the biomass of some important species in the local fishery. Regarding management advice, our results indicate that fishing efforts should not be increased for curimba (Prochilodus lineatus), pintado (Pseudoplatystoma corruscans), and jaú (Zungaro jahu). Additionally, participative management methods are important measures for local fisheries. Finally, additional research is needed to investigate how fishery management can promote the use of multispecific methods (e.g., gillnets) to control introduced speciesThis paper is part of the Ph.D. thesis of JSP under the supervision of CMV at University of Maringá (UEM-Brazil) with scholarship supported by Coordination forthe Improvement of Higher Education Personnel (CAPES) toJSP CAPES also supported MC (Proc. PVE A063/2013, Ed.71/2013)Peer Reviewe