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Community-driven dispersal in an individual-based predator-prey model

Elise Filotas·Martin Grant·Lael Parrott·Per Arne Rikvold
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Abstract

We present a spatial, individual-based predator-prey model in which dispersal is dependent on the local community. We determine species suitability to the biotic conditions of their local environment through a time and space varying fitness measure. Dispersal of individuals to nearby communities occurs whenever their fitness falls below a predefined tolerance threshold. The spatiotemporal dynamics of the model is described in terms of this threshold. We compare this dynamics with the one obtained through density-independent dispersal and find marked differences. In the community-driven scenario, the spatial correlations in the population density do not vary in a linear fashion as we increase the tolerance threshold. Instead we find the system to cross different dynamical regimes as the threshold is raised. Spatial patterns evolve from disordered, to scale-free complex patterns, to finally becoming well-organized domains. This model therefore predicts that natural populations, the dispersal strategies of which are likely to be influenced by their local environment, might be subject to complex spatiotemporal dynamics.

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Elise Filotas, Martin Grant, Lael Parrott, Per Arne Rikvold. 2008-02-19. Community-driven dispersal in an individual-based predator-prey model. https://doi.org/10.1016/j.ecocom.2008.01.002

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