Staff Publications

Staff Publications

  • external user (warningwarning)
  • Log in as
  • language uk
  • About

    'Staff publications' is the digital repository of Wageningen University & Research

    'Staff publications' contains references to publications authored by Wageningen University staff from 1976 onward.

    Publications authored by the staff of the Research Institutes are available from 1995 onwards.

    Full text documents are added when available. The database is updated daily and currently holds about 240,000 items, of which 72,000 in open access.

    We have a manual that explains all the features 

Record number 414999
Title Coexistence of fish species with strongly similar life histories - population dynamical feedback forces species to pick sides
Author(s) Schellekens, T.; Kooten, T. van
Source Yerseke : IMARES (Report / IMARES Wageningen UR C158/11) - 22
Department(s) IMARES Delta
Publication type Research report
Publication year 2011
Keyword(s) vissen - aquatische ecosystemen - predatie - interspecifieke concurrentie - voedselwebben - diergemeenschappen - populatiedynamica - mariene ecologie - fishes - aquatic ecosystems - predation - interspecific competition - food webs - animal communities - population dynamics - marine ecology
Categories Marine Ecology
Abstract Fish generally grow several orders of magnitude between the larval and adult stage. Many ecological properties of organisms are related to body size, and hence small fish often have very different ecological roles than large conspecifics. This also implies that omnivory, the feeding on more than one trophic level by individuals of the same species, is a common phenomenon in fish. Intraguild predation is omnivory in its simplest form, where two species compete for the same resource, but one of the species can also eat its competitor. In models, persistence of both species in such a configuration is difficult to obtain. In marine fish communities however, it is observed routinely. One way in which persistence of omnivorous species can be established is by incorporating it as an ontogenetic diet shift, where small individuals of both species compete, and large individuals of one can feed on the small individuals of the others species. We show in this study that this mechanism can not only lead to persistence of a single omnivorous species, but also to persistence of multiple omnivorous species. This is possible given that the adults have sufficiently different diets. It is shown that, while adults of both species can feed both on small competitors or on the basic resource, due to the population dynamical feedback, one species will in practice act as a predator, while the other acts as prey. This way, a system with two omnivores in practice persists as a tritrophic system. Which of the species assumes which role depends on the specific community characteristics. We show here that by incorporating complex size-dependent feeding relationships in food webs, many more species may be able to coexist than is possible based on either species-level considerations or size spectrum models which do incorporate within-population size differences, but relate diet only to individual body size irrespective of species identity. The mechanism underlying our result may be part of the explanation why fish species with seemingly similar life histories do coexist in marine ecosystems.
There are no comments yet. You can post the first one!
Post a comment
Please log in to use this service. Login as Wageningen University & Research user or guest user in upper right hand corner of this page.