| Summary: | NAFO/PICES/ICES Symposium on Reproductive and Recruitment Processes of Exploited Marine Fish Stocks, 1-3 Octubre 2007, Lisboa Any effect of environment on stock reproductive potential (SRP) will have implications in stock assessment projections of stock biomass and sustainability of commercially important species. Environmental influences on SRP were investigated using the intrinsic rate of population increase r, derived from life table analysis, that incorporates characteristics (e.g. growth rate, fecundity, etc.) which are also associated with SRP. Trends in r were compared among nine Atlantic cod Gadus morhua stocks (Northern Gulf of St. Lawrence, Northeast Arctic, Georges Bank, Gulf of Maine, Baltic, Icelandic, Irish Sea, Flemish Cap, and West of Scotland) with time series varying in length between 22 and 56 years for the time period 1946-2005. Cod west of Scotland had the highest r over the observed period while Northern Gulf of St. Lawrence cod had the lowest r. Tests for significant differences of mean r between stocks indicated five distinct groups, for example, cod from Northern Gulf of St. Lawrence and West of Scotland were significantly different from each other and the other three stock-groups. Stock specific environmental variables, including a global climatic variable (Northwest Atlantic Oscillation) and life history characteristics relative to r were analyzed to further investigate the environmental influences on SRP No
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