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arXiv · 1809.03975

Lotka-Volterra systems with stochastic resetting

Abstract

We study the dynamics of predator-prey systems where prey are confined to a single region of space and where predators move randomly according to a power-law (L\'evy) dispersal kernel. Site fidelity, an important feature of animal behaviour, is incorporated in the model through a stochastic resetting dynamics of the predators to the prey patch. We solve in the long time limit the rate equations of Lotka-Volterra type that describe the evolution of the two species densities. Fixing the demographic parameters and the L\'evy exponent, the total population of predators can be maximized for a certain value of the resetting rate. This optimal value achieves a compromise between over-exploitation and under-utilization of the habitat. Similarly, at fixed resetting rate, there exists a L\'evy exponent which is optimal regarding predator abundance. These findings are supported by 2D stochastic simulations and show that the combined effects of diffusion and resetting can broadly extend the region of species coexistence in ecosystems facing resources scarcity.

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BibTeXRIS

Gabriel Mercado-Vásquez, Denis Boyer. 2018-09-11. Lotka-Volterra systems with stochastic resetting. https://doi.org/10.1088/1751-8121%2Faadbc0

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