The modeling of prey-predator interactions is of major importance for the understanding of population dynamics. Since the classical modeling of Lotka-Volterra, these interactions have usually been modeled using ordinary differential equations. Yet, this approach has the drawbacks of assuming continuous population variables and of being deterministic, despite the stochastic nature of predation.
We propose a general approach to stochastic modeling based on the concept of functional response for a prey depletion process with a changing number of predators. Our model can involve any kind of functional response, and permits a likelihood-based approach to statistical modeling.
To illustrate the method and its benefits, we compare the outcomes of our model with a deterministic counterpart used to model a Cassida rubiginosa- Polistes dominulus system in natural conditions (Bacher & Schenk 2002).
Results/Conclusions
In both cases, the predation was found to be Holling type III, reflecting the ability of the predator to regulate its prey. But, our model provides supplementary information: it suggests that the prey depletion census should have been performed more often, and that predation features were significantly different between the two years for which data are available.
