Which benthivorous fishes feed greedily after bottom trawling? (Charlotte Desmet)

Jozefien Derweduwen (Copromotor)

    Activiteit: OverigeAndere soorten (prijzen, externe en andere activiteiten) - (Co)promotor masterthesis

    Beschrijving

    This study aims to investigate whether the deeper penetration of a tickler chain beam trawl
    provides more food resource for scavengers than the less destructive pulse trawl. Influence on
    fish size and the start time of feeding after trawl disturbance were researched. Stomach contents
    were analysed from plaice, caught in the Frisian Front in the southern North Sea. Multivariate
    statistical analysis indicated that a significant higher stomach fullness index, higher number of
    taxa and higher number of individuals were observed seven hours after a tickler gear passage.
    Scalibregma inflatum was most responsible for numerical abundance change in community
    structure. Plaice mainly preyed upon this low-energy species seven hours after a tickler gear
    passage, whereas only low occurences were seen of high-energy species, Bivalvia sp (Ensis),
    Gobiidae sp and Callianassa subterranean. Our study demonstrates that plaice exhibits a foraging
    strategy with high energy costs, leading to lower condition of this flatfish species. Hence, the
    deployment of tickler chain beam trawling might negatively affect the plaice stock and its
    fisheries.
    Periode1-feb-201510-jul-2015
    Gehouden opILVO-Ghent University, België