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bioRxiv · 10.1101/2020.08.23.263384

Crowding Effects In An Empirical Predator-Prey System

Subbey, S.·Frank, A.-S.·Kobras, M.
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Abstract

AO_SCPLOWBSTRACTC_SCPLOWThis paper uses a Lotka-Volterra (predator-prey) modeling framework to investigate the dynamical link between the biomass of an empirical predator, and that of its prey. We use a system of ordinary (ODE) differential equations to describe the system dynamics, and derive theoretical conditions for stability, in terms of system parameters. We derive the empirical system parameters by fitting the ODE system to empirical data, using non-constrained optimization. We present results to show that the predator biomass is regulated by that of the prey. Furthermore, that the system dynamics is subject to Hopf bifurcation, conditioned on independent second-order terms in the ODE system. In ecological terms, the findings translate into evidence for existence of population crowding (density) effects.

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Subbey, S., Frank, A.-S., Kobras, M.. 2020-08-24. Crowding Effects In An Empirical Predator-Prey System. https://doi.org/10.1101/2020.08.23.263384

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