The effect of fish life-history structures on the topologies of aquatic food webs

Abstract

Biological organisms can vastly change their ecological functionality due to changes in body size and diet across their life. Consequently, it has been increasingly recognized that to attain sufficient biological realism, food webs may need to include life-history structures. The objective of the work is to study theoretically whether and how the inclusion of life-history structures affects the food web topology. Topological research was done by applying network theory metrics for three different food web types with two different sizes that were generated by using the niche-model. The dynamical modeling was performed by using an allometric trophic network modeling approach. The different types included food webs with and without the life-history structure for top predators (three fish species). Each of the generated random food webs analyzed reached dynamical equilibrium conditions with respect to the biomass densities of the species prior to the network analysis. Our results suggest that food web topologies are not largely affected by the inclusion of age- or stage-structure. In addition to the topological study, the relationship between the metrics used in this work was investigated by using Pearson correlation. Results suggested that only a few pairs of metrics had a strong positive correlation and most of the correlations did not change with food web size or type.