Patterns of resource utilisation within and between species affect the dynamic dimensionality and stability of ecological communities
2016 (English)Manuscript (preprint) (Other academic)
In many ecological communities, individuals within species pass through a wide spectrum of sizes, spanning several orders of magnitude, during the independent part of their life cycle. Such a large size-variation within a species will affect the structure of its niche, since the size of an individual affects the type of prey it can consume as well as what predators will attack it. Here we use highly resolved individual-based empirical data to investigate patterns in the niche structure of several aquatic food webs. We quantify within and between species components of resource use in these webs and explore its consequences for dynamical dimensionality and community stability using simple food web models with stage-structured consumer species. Among the natural food webs there are webs where species overlap widely in their resource use while the resource use of size-classes within species differs. There are also webs where differences in resource use among species is relatively large and the niches of sizeclasses within species are more similar. Model systems with the former structure are found to have low dynamical dimensionality and to be less stable compared to systems with the latter structure. Thus, although differential resource use among individuals within a species is likely to decrease the intensity of intraspecific competition and favor individuals specializing on less exploited resources it can destabilize the community in which the individuals are embedded.
Place, publisher, year, edition, pages
IdentifiersURN: urn:nbn:se:liu:diva-123968OAI: oai:DiVA.org:liu-123968DiVA: diva2:894602