G

instantaneous rate of growth (a measure of the weight increase, the natural logarithm of the ratio of final weight to initial weight of a fish in a unit of time, usually a year. When applied collectively to all fish of a given age in a stock, the possibility of selective mortality must be considered (Ricker, 1975). The formula is g = [Ln(Wt) - Ln(W0)]/(t1-t0) where Wt is the weight of the fish after t1 days and W0 is the initial weight).