Current State of Knowledge and Conservation Perspectives on the Cetaceans of the Aegean Sea

The underwater habitat complexity of the Aegean Sea renders it home to a diversity of cetacean species. From shallow-diving piscivores to teuthophagous deep divers, this sea hosts seven regular cetacean species (Delphinidae, Phocoenidae, Physeteridae, and Ziphiidae), while five more species have been reported as visitors. Despite this high biodiversity, little is known about this taxon, with most available information referring only to presence data. Due to an ever-increasing human development in the area, seven threats can be identified so far: interactions with fisheries and plastic debris, noise and chemical pollution, shipping, climate change, and epizootics. The concurrent absence of abundance data for these apex predators and the lack of protection areas and law enforcement undermine the survival of the cetaceans in the Aegean Sea. Based on these deficiencies and the scarce governmental funding, we propose that research effort should focus on three main topics: abundance, fine-scale distribution, and ecology. Only with this information available, the monitoring of anthropogenic threats will allow the assessment of the effectiveness of potential conservation measures.