The strength of simulated indirect interaction modules in a real food web

There is an increasing body of literature on the topological analysis of modules (motifs, building blocks) in different networks. Most of these results are of descriptive, comparative and statistical nature, while dynamical simulations of their behaviour are missing. We present a stochastic food web simulation and study the relative strength of different simple food web modules. We found that (1) the effects of prey groups on predators are significantly stronger than other effects, (2) indirect loops have strong effects only on mean population sizes, not on their variabilty, and (3) some short indirect interactions are not stronger than some longer ones. We believe that these findings may contribute to systems-based conservation practice in the future. © 2012 Elsevier B.V.