Commercial fisheries in large temperate and subtropical floodplain rivers Volga (Russia) and Paraná (Argentina): resilient to climate change?

GÓRSKI KONRAD; ANA PIA RABUFFETTI; ESPÍNOLA LUIS ALBERTO; NAGELKERKE LAJ; WINTER HV; DE LEEUW JJ; MININ AE

Simposio; Adaptation of inland fisheries and aquaculture to climate change.EIFAAC International Symposium; 2017

Inland Fisheries Institute; FAO, Ministry of Maritime Economy and Inland Navigation

Periodic flooding (flood pulse) plays a key role in the ecology of floodplain rivers. Flood pulse characteristics e.g., magnitude, duration, are the primary driving force of the recruitment of commercially exploited fish in these systems. These flood pulse characteristics are primarily driven by climatic and resulting hydrologic fluctuations. We analysed the effects of hydrologic fluctuations in the last decades of the 20th century on fisheries catches in the Lower Volga and the Middle Paraná rivers. We found that large floods resulted in increased abundances and commercial fish catches in both rivers, probably due to enhanced recruitment. Specifically, large floods produced increased fish biomass one year later in the Volga and two years later in the Paraná. This effect was the strongest for species that use floodplain habitats as areas of larval nurseries. We discuss potential changes in fisheries catches in these rivers in projected future climate scenarios.