Site influence in parasite distribution from fishes of the Bonifacio Strait Marine Reserve (Corsica Island, Mediterranean Sea).

The spatial distribution of parasite communities from teleost fishes (Diplodus vulgaris, Mullus surmuletus, Pagellus erythrinus, Phycis phycis, Scorpaena scrofa and Symphodus tinca) was studied in the Bonifacio Strait Marine Reserve (Corsica Island) with different protection levels. Canonical correspondence analysis was used to study spatial patterns and to quantify the importance of site influence on parasite communities. To supplement these results, we used the indicator species analysis (Indval) to identify parasite species as bioindicators of a given ecosystem. Moreover, fish spatial distribution in the marine reserve was evaluated in order to link parasite species occurrence and fish abundance. Several parasite species were associated with a specific site, and some of them were considered as site bioindicators, especially in the western part of the protected area (Bruzzi and Moines Islands). However, the relative abundance of fish followed a different spatial pattern. Stronger fish abundance was observed in the eastern part of the reserve (Lavezzi Islands). The parasite species were correlated to sites inside as well outside the reserve. The parasite distribution seemed not to be influenced by the protection status of the site. Furthermore, in our study, most of the parasite species were not linked to a site. The most important factor influencing their distribution was host specificity. This suggested that the parasite life traits history remained a fundamental determinant in the community composition.