Starting/ending date: 01/02/2014-30/06/2014
Financing:  250.000,00 €
National project
Dr A. Machias, Marine Biological Resources

ECOsystem effect of fisheries DISCards.The European Commission has decided the gradual banning of fisheries discards by imposing obligation for landing of unwanted catch as key point of the reform of the Common Fishery Policy. Discards constitute food source for several groups of species (especially seabirds and benthic scavengers) and cause alteration of trophic interactions which affect ecosystem functioning and structure.

The effect of a discards ban on the environment is largely unknown, especially for oligotrophic systems like the Mediterranean Sea. ECODISC aims at understanding how fisheries discards affect ecological processes and biogeochemical cycles, and how this can be managed. These are addressed by a series of experiments and tools (maps, statistical and mathematical models) that aim to elucidate discards fate and their use as a food source by the ecosystem communities, and integrate this information to explore ecosystem effects of a possible application of partial or full discards ban. First the spatio-temporal distribution of discards in the Ionian Sea will be analyzed, discard management scenarios that are likely to be applied will be defined and resultant changes in discards quantities will be explored. A series of on board experiments will shed light on the survival of discards, their fate after sinking and their use by opportunistic benthic scavengers. A series of research trips is designed to explore discards use by seabirds and analyze their dependency by this food levy.

The information gained will be integrated in an existing ecosystem model which will be updated to focus on the interactions of discarding with seabirds and benthic communities. The model will be used to simulate the defined discards ban management scenarios and results will be used to assess if discards play important role for the conservation of seabirds and/or the sustainability of fisheries resources. Finally, based on the model outcomes, management strategies will be evaluated.