The impact of behavioral plasticity at individual level on domestic cat population dynamics

An extension of a model studying the population dynamic consequences of int ra-individual variability in behavior is presented. Individuals can adopt t hree different tactics: hawk, dove and bully. We consider a population of i ndividuals that compete for some resources. The same individual experiences the different tactics in his life and it is assumed that the game is playe d at a fast time scale in comparison to population dynamics. This fast part of the model is coupled to a slow part, which describes the growth of each sub-population. By use of aggregation methods, we obtain an equation gover ning the total population at the slow time scale. This equation is a logist ic one whose r and K parameters are related to the payoff of the tactics. T he model is applied to the case of domestic cat populations. Results show t hat the highest population density corresponding to urban environment is re ached when all individuals are bully. We also obtain a gradient from rural to urban environments, respectively corresponding to aggressive to non-aggr essive individuals. The results of the model are consistent with empirical data: high-density populations of domestic cats are mainly bullies, whereas low-density populations are mainly hawks. (C) 2000 Elsevier Science B.V. A ll rights reserved.