Common dolphins (Delphinus delphis) status in the central and southern Mediterranean around the Maltese Islands

Abstract

Since 1997, a conservation biology research project focusing on cetaceans in the Central and Southern Mediterranean Sea around the Maltese Islands has managed to increase accurate information of the various species inhabiting these waters (Vella, 1998; 2000a; 2000b). Among the species studied, this paper focuses upon the common dolphin, Delphinus delphis in the Mediterranean. This species/subpopulation rated as endangered in the Mediterranean (EN A2abc - IUCN 2003 - http://www.redlist.org) necessitates particular conservation assessment, monitoring and management planning in this region (IUCN, 2003; Reeves et al., 2003). This ongoing longterm research therefore also aims at contributing valuable information (Vella, 2000b) required in relation to the Agreement on the Conservation of Cetaceans of the Black Sea, Mediterranean Sea and Contiguous Atlantic Area (ACCOBAMS). Although Mediterranean cetaceans are legally protected by Maltese law, through specific legal notices, this field conservation research is, to date, the only scientific effort around the Maltese Islands that may furnish the required details for local conservation measures to be implemented. Common dolphin distribution, abundance, habitat preference, behaviour, and associations with fisheries that are exploited in the same area are among the parameters studied. Marine habitat degradation and resource over-exploitation are considerations that need to be addressed since both may affect cetacean survival in the region. Part of the study area, closer to the Maltese Islands is shown in Fig.1, and includes most of the fishing area utilised by Maltese fishermen.