Spatiotemporal patterns of distribution of large predatory sharks in Calabria (Central Mediterranean, Southern Italy)

During the 2000-2009, a survey study on the spatiotemporal patterns of distribution of largepredatory sharks was carried out in the Calabria region. A total of 12 species were recorded andamong them the blue shark Prionace glauca and the bluntnose sixgill shark Hexanchus griseus werethe most common ones. Also of interest was the frequency of species such as Carcharodon carcharias,Sphyrna zygaena and Cetorhinus maximus. 57% of all reported records derived from the Tyrrhenianside of the region and 43% on the Ionian side. A significant relationship between season of the yearversus number of records was found, but this could be related to the small number of observers thatwere active during the winter months. The presence of Sphyrna lewini is reported for the study area;this species was previously recorded only in the western part of the Mediterranean Sea. This paperalso provides evidence of the second and first documented accounts of white shark predation uponTursiops truncatus and Stenella coeruleoalba, respectively, in the Mediterranean Sea. The recoveringof Ionian Sphyrna zygaena populations and the declining of Lamna nasus populations were alsonoted.