One-way Gene Flow by Stocking and Its Effects on a Fish Population

Abstract

In local populations, one-way gene flow occurs during a stocking program. Using a simple recursion formula and information on genetic fitness, the genetic influence on a natural population is investigated when a one-way gene flow takes place at a constant rate. One-way gene flow alters and finally replaces the genetic composition of a natural population when hatchery stocking continues over a long period of time. In particular, if the genetic composition of the stocked individuals differs from that of the optimal one, stocking prevents maximization of population fitness. In the light of these findings we emphasize the importance of using the seeds which are closely related to the gene composition of the natural population.