Analysis of the epibiont communities of the loggerhead sea turtle Caretta caretta recovered along the southern Italian coasts

Sea turtles (Cheloniidae) offer a suitable substrate for the settlement of various epibiont organisms. The structure of the epifauna communities associated with sea turtles provides information on the movement and habitats most frequented by Cheloniidae. Thanks to the collaboration with the Sea Turtle Recovery Centers (STRC) of Policoro (MT) and Molfetta (BA), the communities of epibionts present on individuals of Caretta caretta, caught or stranded on the beach in the Northern Ionian Sea (ION) and Southern Adriatic Sea (ADR), have been characterized. The study involved a samples of 142 turtles (108 STRC Policoro; 34 STRC Molfetta), and aimed to 1) identifying temporal differences in the structure of epifauna communities and 2) comparing community structures in the two areas, involved a sample of 142 turtles (108 STRC Policoro; 34 STRC Molfetta). Data obtained from the ION individuals were used to test seasonal differences. Differences between ION and ADR samples were evalueted in terms of species richness, abundance and the community structure of epibionts, using univariate and multivariate analyses. Measures of the CCL (Curved Carapace Length) were obtained to identify the predominant age classes of the turtles recovered in the two areas. Finally, an analysis of taxonomic distinctness was performed to further highlight the differences. Comparing the communities on the turtles in the two areas, a greater number of taxa were found in the ION sample than in the ADR sample. The average size of the turtles recovered in the ION was significantly smaller than that of ADR and lastly a greater taxonomic diversity was seen in the ION sample compared to that of the ADR.