Positive steady state in multi-species models of real food webs

Real food web data available in the literature presents us with the relations between various species, sizes of these species, metabolic types of the species and other useful information, which allows us to define parameters for the mathematical dynamical models of these food webs, and perform theoretical studies of these models. Unfortunately, the researches often face the problem of the extinction of the species in such situations, which could be an important limiting factor. In this paper, we propose a simple algorithm of parameterisation that leads to the existence of positive steady state and improves persistence of the species in multi-species models of real food webs.