Results
Assessment was based on evaluation of trends in acoustic survey data (1975 – 1994) and bottom trawl surveys (1996 – 2019: upper right figure – Canadian spring surveys biomass index; 1985 – 2019: lower right figure – Canadian spring surveys mean catch). Bottom-trawling is not a satisfactory basis for a stock assessment of a pelagic species. The assessment is only sensitive to large-scale fluctuations in biomass and abundance. Therefore, although the next full assessment is in principle scheduled for 2024, SC recommends that this stock be monitored in future by interim monitoring reports only, until such time conditions change to warrant a full assessment.
Biomass Human impactLow fishery related mortality due to moratorium and low bycatch in other fisheries. Other sources (e.g. pollution, shipping, oil-industry) are considered minor.
Biological and environmental interactionsChanges in growth, maturity and recruitment are linked to temperature on the Grand Banks. The Grand Bank (3LNO) EPU is currently experiencing low productivity conditions and biomass has declined across multiple trophic levels and stocks since 2014.