Mediterranean Marine Heatwave 2023 Impacts

This technical report assesses the impacts of the 2023 Mediterranean marine heatwave (MHW) on marine biodiversity and fisheries in Italian waters. It focuses on the spread of two invasive species, Callinectes sapidus (Atlantic blue crab) and Hermodice carunculata (bearded fireworm), particularly in the Po River Delta and along the coasts of Sicily. The report evaluates how increased seawater temperatures during the MHW have contributed to the rise in biomass of these species, which pose significant threats to local fisheries and human health. The study also analyzes socio-economic impacts through fish market data and surveys from the fishing community, highlighting the economic losses attributed to the invasive species. Additionally, it discusses potential strategies for mitigating the ecological impact of these invasions. The findings underscore the need for interdisciplinary collaboration to address the challenges posed by climate change and biological invasions in the Mediterranean region.