Trophic structure in the Gulf of Lions marine ecosystem (north-western Mediterranean Sea) and fishing impacts
|Author(s)||Banaru Daniela1, 2, Mellon Capucine1, Roos David1, Bigot Jean-Louis1, Souplet Arnauld1, Jadaud Angelique1, Beaubrun P.3, Fromentin Jean-Marc1|
|Affiliation(s)||1 : IFREMER, Ctr Halieut Mediterraneen & Trop, Lab Ressources Halieut, F-34203 Sete, France.
2 : Aix Marseille Univ, Mediterranean Inst Oceanog, UMR 7294, UR 235, F-13288 Marseille 09, France.
3 : Univ Montpellier, Ecole Prat Hautes Etud, Montpellier, France.
|Source||Journal Of Marine Systems (0924-7963) (Elsevier Science Bv), 2013-02 , Vol. 111 , P. 45-68|
|WOS© Times Cited||51|
|Keyword(s)||Gulf of Lions, Ecopath with Ecosim, Food web, Fishing impacts|
|Abstract||The Gulf of Lions ecosystemwas described using the Ecopath mass-balancemodel to characterise its structure and functioning and to examine the effects of themultispecific fisheries operating in this area. The model is composed of 40 compartments, including 1 group of seabirds, 2 groups of etaceans, 18 groups of fish, 12 groups of invertebrates, 5 groups of primary producers, detritus and discards. Input datawere based on several recurrent scientific surveys, two alternative datasets for fishing data, stock assessment outputs, stomach content analyses and published information. Results showed that the functional groups were organised into five trophic levels with the highest one represented by dolphins, anglerfish, Atlantic bluefin tuna, European hake and European conger. European pilchard and European anchovy dominated in terms of fish biomass and catch. Other fish with high biomass such as Atlantic mackerel and blue whiting were highly important in the food web. Seabirds, dolphins and cuttlefish–squids represented keystone species. Important coupled pelagic–demersal–benthic interactions were described. The 7 different fisheries analysed were operating at mean trophic levels situated between 2.6 for
small artisanal boats, and 4.1 for purse seines (>24 m) targeting large pelagic fish, indicating an intensively exploited ecosystem. Large trawlers (24–40 m) had the highest impact on most of the groups considered; while purse seines (12–24 m) targeting small pelagic fish had the lowest impact. Preliminary results highlighted the importance of data sources for further ecosystem and fisheries analyses and management scenarios.