Future climate change impacts on anchoveta (Engraulis ringens) in the Northern Peru Current Ecosystem

The Northern Peru Current Ecosystem (NPCE) is the most productive ecosystem in terms of fish biomass and sustains the worlds largest small pelagic fishery, the Peruvian anchovy fishery. A cooling of this system has been observed during recent decades but the potential regional impacts of rising atmospheric CO2 concentrations on upwelling dynamics and productivity are still unknown. We used the ecosystem model OSMOSE to forecast the impacts of several scenarios of climate change on Peruvian anchovy in the NPCE. The OSMOSE model was forced by plankton production and climate drivers from the Earth System Models IPSL CM5A-LR and GFDL-ESM2M for the period 2009-2100. For each earth system model, representative concentration pathways (RCP) scenarios 2.6, 4.5, 6.0 and 8.5 were run. Our results showed that an optimistic trajectory for anchovy is a reduction of biomass at a rate of 14% per decade until mid-21st century, followed by a collapse and late recovery by the end of the 21st century, while no changes in the spatial distribution of the population were observed. The pessimistic trajectory for anchovy is a reduction of biomass of 22% per decade, with a collapse after 2020 and near extinction by 2060, with a spatial displacement of the population to the south and to more coastal areas. Further research is needed to include additional key environmental variables such as oxygen as well as more realistic fisheries management intervention scenarios to evaluate future options for the sustainability of anchovy resource and fisheries.