An age-structured fish population model with coupled size and population density
In this paper an age-structured fish population model in which fish size is included as a dynamic variable is formulated and analyzed. The main features of the model include size-dependent growth and mortality of young-of-the-year fish as well as size-related fecundity of adult females. The inclusion of cannibalism of young-of-the-year fish by yearlings, as it is represented in the model, can lead to some interesting stability behavior such as the existence of multiple equilibrium states. Depending on initial conditions, the population may evolve to either of two stable equilibrium states: one with relatively large numbers of small fish or one with relatively small numbers of large fish.
existence of multiple equilibrium states
scientific article; zbMATH DE number 4014511