Stable coexistence in a Lotka-Volterra model with heterogeneous resources and intraguild predation.
In this study we model population dynamics in a three-species food web with heterogeneous resources and intraguild predation by using a nonspatial Lotka-Volterra system with a density-dependent interaction of resource items. The model consists of two predators with an intraguild predation (IGP) relation competing for a common resource. The resource is subdivided into subpopulations of different quality that are distinguished by grazing rates of the two predators, contact rates between subpopulations and mortality rates. The proposed system describes an exchange of traits between species from distinct subpopulations by using a species interaction term. In particular, we examine the percentage of stable coexistence solutions versus resource carrying capacity and contact rates between distinct resource pools. We also present a numerical comparison of the percentage of stable food webs found for different numbers of subpopulations. While at high enrichment no stable coexistence was found in the IGP system with a single resource, our model predicts a stable coexistence of two IGP-related predators and resources at high and intermediate enrichment already at a low contact rate between subpopulations.
Alfred-Wegener-Institut Helmholtz-Zentrum für Polar und Meeresforschung, Biologische Anstalt Helgoland, Kurpromenade 201, D-27498 Helgoland, Germany.
Elena Y
EY
Shchekinova
Alfred-Wegener-Institut Helmholtz-Zentrum für Polar und Meeresforschung, Biologische Anstalt Helgoland, Kurpromenade 201, D-27498 Helgoland, Germany.
Martin G J
MG
Löder
Alfred-Wegener-Institut Helmholtz-Zentrum für Polar und Meeresforschung, Biologische Anstalt Helgoland, Kurpromenade 201, D-27498 Helgoland, Germany.
Karen H
KH
Wiltshire
Alfred-Wegener-Institut Helmholtz-Zentrum für Polar und Meeresforschung, Biologische Anstalt Helgoland, Kurpromenade 201, D-27498 Helgoland, Germany.
Maarten
M
Boersma
D000818:Animals; D020387:Food Chain; D008962:Models, Theoretical; D011157:Population Dynamics; D011235:Predatory Behavior; D062211:Spatio-Temporal Analysis