Fisheries Centre research reports, Vol. 29, no. 3

This report presents the key results of a multi-year activity of the Sea Around Us devoted to assessing the status of marine fisheries globally. This was accomplished by estimating, for the Exclusive Economic Zones (EEZ) of all maritime countries and the high seas, the fraction currently left in the sea of the exploited populations of fish and invertebrates that occurred before the onset of large-scale industrial fishing. More precisely, the ‘fraction left’ is the current biomass (B) of a stock relative to its initial biomass (B0), i.e., B/B0. This fraction was estimated for multiple exploited populations (or ‘stocks’) by applying a versatile stock assessment method (CMSY++), whose main features are also described. Altogether, over 2,500 stocks of fish and marine invertebrates (mainly crustaceans such as lobsters and mollusks such as squids) were assessed in the EEZs of countries on five continents and the high seas. These assessments were based mainly on long catch time series (typically 1950 to 2018) but considered, wherever they were available, the results of earlier assessments made by national or international fisheries management bodies. Thus, the evaluations of fisheries status presented herein are not defined by data scarcity; rather, we used all available data pertinent to the status of fisheries in all maritime countries to reduce the uncertainty inherent in all stock assessments. The detailed results of these stock assessments and their supporting data are available on the Sea Around Us website (www.seaaroundus.org). These results will also be used by the Flourishing Ocean Initiative of the Minderoo Foundation, which kindly funded a large part of our catch reconstruction update to 2018 and the stock assessment work described herein.Science, Faculty ofNon UBCOceans and Fisheries, Institute for theUnreviewedFacultyResearche