The common bottlenose dolphin (Tursiops truncatus) hereafter referred to as “the bottlenose dolphin” is possibly the best known and most widely distributed of all Delphinidae species. The basic biology of this species is well documented. It has a fusiform body shape (streamlined); body colour varies from dark grey on the dorsal cape to pale grey on the side and white on the underside, which may have a pinkish glow when the summer water temperature is high. The bottlenose dolphin measures between 1.9 m to 4 m when adult and weighs anything from 100 kg to 500 kg. In the Adriatic, animals usually reach up to 3 m in length and weigh about 200 kg. Dolphins must surface every few minutes to breath. The single blowhole is located on the dorsal surface of the head and is covered by a muscular flap that provides an airtight seal when diving. Bottlenose dolphins remain submerged for 4 – 7 minutes when foraging for fish. Bottlenose dolphins feed mostly on benthic fish and small squids, and therefore are often in direct competition with fishermen. They are famous for their curiosity and this makes them prone to entanglement, particularly in gillnets, which in turn is a major form of premature death for the species. Although there is no current worldwide estimation of their population, based on the aerial surveys we carried out, their number in the Adriatic is estimated at around 10,000 individuals. Pollution, overfishing and habitat destruction reduces the numbers of these dolphins and confines them to limited habitats.
