Tropho-ethological polymorphism of fish as a strategy of habitat development: a simulation model

This paper presents a simple simulation model of temporal and spatial dynamics of polymorphic populations of fish using the well-established model system Stella. The model explores the hypothesis that intraspecific competition has played a major role in the development of tropho-ethological polymorphism in fish populations. This hypothesis is illustrated by the example of the population of bream, Abramis brama, inhabiting Rybinsk reservoir, Russia. The presence of several tropho-ethological groups within a population is an important ecological and evolutionary strategy, which helps fish to develop new habitat and, therefore, increases population survivorship, what can lead to appearance of new species.