Ricker curve

Ricker curve
named for William Ricker, a Canadian fisheries biologist, this is a mathematical model of fish population dynamics. A graph of mature progeny and spawners is used to determine average maximum catches for a fishery. One line on the graph is the line of natural replacement where spawners are replaced by an equal number of progeny. The natural equilibrium point is where spawners equal progeny without fishing. Past this point crowding is a factor depressing the numbers of fish through egg loss on spawning beds. A curved line shows the maximum sustainable catch (see Ricker (1975) for details)

Dictionary of ichthyology. 2009.

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  • recruitment curve — a graph of the progeny of a spawning at the time they reach a specified age, e.g. the age at which half of the brood has become vulnerable to fishing, plotted against the abundance of the stock that produced them (Ricker, 1975). Also called… …   Dictionary of ichthyology

  • reproduction curve — a graph of the progeny of a spawning at the time they reach a specified age, e.g. the age at which half of the brood has become vulnerable to fishing, plotted against the abundance of the stock that produced them (Ricker, 1975). Also called… …   Dictionary of ichthyology

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