Acronym NA
Category
Fisheries
Title Valutazione dell'efficacia delle zone interdette alla pesca a strascico attraverso lo studio delle prede e dei predatori della triglia, Mullus barbatus; Sottoprogetto: Ruolo trofico di Mullus barbatus in aree con diverso grado di protezione - Evaluation of the efficacy of areas forbidden to trawl fishery through the study of prey and predators of red mullet, Mullus barbatus; Subproject: Trophic role of Mullus barbatus in areas with different degree of protection Programme National Programme
Instrument (FP6)
Contact Type (FP7)
Strand (Interreg)
NA
Theme (FP7)
Activity Area (FP6)
Regional Area (Interreg)
Action (COST)
NA
Specific Programme (FP7)
NA
Funding source National Coordinator Franco Andaloro Coordinator email franco.andaloro@isprambiente.it
Coordinator institution
ISPRA - Italian National Institute for Environmental Protection and Research (Italy)
Institutions involved
NA
Start year 2004 End year 2006 Funding (€) € NA Website NA Summary The ecosystem approach is the most topical management model for the achievement of sustainable and responsible fishery. A shift from the use of provisional models based on population dynamics or from a single-species management approach, to a holistic vision of aquatic ecosystems which takes into account its multi-specific context, particularly in those basins characterized by great biodiversity, was observed. The energy flows between the different levels of a food web, influence the survival, abundance and quality of the resources. The knowledge of the diet of animal species provides information on the their trophic level and contributes to defining their ecological niche and therefore functional role in the environment, providing precious information for a correct exploitation and conservation of the fish resources. More and more evidence shows that the pressure of fishing activities can alter the trophic structure and therefore destabilise the marine ecosystems. The use of areas subject to partial or total constraints of the fishing activities is important for the acquisition of information on the structural and functional characteristics of the community that can be compared with those of adjacent areas subject to intense fishing exploitation. The specific objectives of the project can be synthesized in the following points: (1) Study of M. barbatus feeding habits by means of stomach contents analysis; (2) Study of the ontogenetic variations of M. barbatus diet; (3) Study of the significance of the institution of areas off-limits to trawl fishing on the trophic role of M. barbatus within the soft bottom communities. The study areas were four gulfs located along the northern coast of Sicily: Castellammare del Golfo (GCAST), Patti (GPATT), Termini Imerese (GTERM) and S. Agata di Militello (GSANT). Of these, GCAST and GPATT are considered marine protected areas, given that trawl fishing is prohibited, whereas GTERM and GSANT represent the control areas where the ban does not apply and thus subjected to intensive fishing activity. The specimens sampling was conducted by means of trawl fishing. The fishing campaigns were carried out in the period between the 23rd of May and the 14th of June 2005. . The results obtained in this study allow us to gather a number of considerations. First of all, the prey found in the stomach contents and the results obtained are only partially in accordance with the studies of other authors. Previous studies have shown that M. barbatus is a benthic carnivorous species, feeding upon a limited number of prey categories (mostly molluscs, polychaetes and crustaceans) belonging to taxonomic groups closely related to the benthos. The presence within the analysed stomachs of species typically supra-benthic (which therefore move in the water layer close to the bottom), such as the mysidaceans, the crustacean Processa and Crangonidae and teleosts at juvenile stage allows us to suppose a certain trophic adaptability of the red mullet also on resources not strictly benthic. Ontogenetic variations in the diet of M. barbatus were observed in protected as well as non-protected gulfs. The diet of M. barbatus in protected and non-protected areas was different, giving evidence of a significant impact of trawl fishing activity on the trophic structure of the system analysed. The major differences in the trophic structure of the protected gulfs compared to the non-protected ones were determined by a higher consumption of polychaetes, bivalves and epi-benthic crustaceans in the former. On the contrary, in the gulfs where trawl fishing was allowed, a predominance in the diet of crangonids, processids and mysidaceans was observed. Our results highlight that in protected gulfs the diet of the red mullet was heterogeneous, with infaunal and epifaunal organisms contributing the most to its diet. In non-protected gulfs, where trawl fishing is permitted, the diet was more homogenous based almost entirely on supra-benthic organisms.
Goals:
(1)study of M. barbatus feeding habits by means of stomach contents analysis; (2) study of the ontogenetic variations of M. barbatus diet; (3) study of the significance of the institution of areas off-limits to trawl fishing on the trophic role of M. barbatus within the soft bottom communities.
Keywords
Trawling;
Red mullet;
Fish;
MPA;
Fisheries management;
Food web;
Marine Region
48
South Tyrrhenian Sea (GSA 10)
1
Marine Region Map
