Parasitofauna del salmonete de roca (Mullus surmuletus) en el Mediterráneo español: variabilidad espaciotemporal y su implicación pesquera

An investigation on the fauna of metazoan parasites of the striped red mullet, Mullus surmuletus, in the Spanish Mediterranean has been carried out. It represents the most detailed parasitological study of this species in this region to date. Our research focuses on the advantages and limitations of the use of parasites as population tags, and as a tool to trace the origin (spatial and temporal) of captures of striped red mullet. The main goal is to provide useful, yet critical evidence to achieve a sustainable management of this overexploited fish species. Overall, we analyzed 1024 fish during the period 2003-2006: 1000 fish were collected from 5 localities of the Spanish Mediterranean (from north to south: Barcelona, Burriana, Santa Pola, Roquetas de Mar and Fuengirola), and 100 from 2 Tusinian localities, i.e., Sfax y Zarzis. In addition, a total of 104 fish was also collected for validation of predictive models, including fish from other localities from Mediterranean (Palamós, Peñíscola, Valencia) and Atlantic (Barbate) localities, as well as fish from the 5 main Spanish localities of the study that were larger or smaller than those used to build the predictive models. This thesis is divided into 3 main sections: 1. A taxonomic section, in which parasite taxa are identified and described in detail, or eventually classified as new species. This long section is necessary to reliably perform research on parasites as biological tags. 2. An ecological (biogeographical) section in which diversity patterns of parasites from striped red mullets are examined at a large geographical scale (the whole Mediterranean Sea). This analysis allows a better understanding of the processes that generate patterns of diversity (e.g., species’ turnover) and abundance at smaller spatial scales. 3. A section about the use of parasites as biological tags, in which we firstly investigate the validity of some implicit assumptions usually adopted in studies about the use of parasites to discriminate stocks and traceability of fish. Then, we investigate the use of parasites for both stock discrimination and traceability in the case of red-striped mullet at several spatial scales and between different seasons.