Large fisheries declines linked to compound and extreme climate events

This study quantifies the effects of annual temperature extremes (TempX), productivity extremes (NPPX), and their compounded co-occurrence on local fish stocks and fisheries worldwide. Using three decades of global data encompassing 6,659 fisheries and environmental time-series for 1,246 exploited fish and invertebrate species across 254 Exclusive Economic Zones (EEZs). The authors applied a risk-based framework and statistical modelling to assess how extreme high temperatures and low ocean productivity affect the likelihood of extreme low fisheries catches. 

The study finds that compound high-temperature and low-productivity extremes amplify the risk of extreme low catches beyond those associated with individual extremes and identifies compound ocean extremes as an emerging global risk to fisheries. The authors project that, without adaptation, the risks from extreme events will strongly intensify by the mid-21st century, with the share of fish stocks experiencing extreme low catches in vulnerable EEZs increasing from about 11 per cent in the early 1990s to almost 16 per cent by mid-century. The study underscores the urgent need for climate-adaptive fisheries management and recommends adaptive harvest control rules, early warning systems, diversification of target species, and strengthened monitoring and forecasting capacity. The authors highlight that targeted investments and international support will be vital, particularly for socio-economically vulnerable countries, to build resilience and respond effectively to the compounding pressures of physical and biogeochemical extremes.