Cetacean records and encounter rates in the northern Adriatic Sea during the years 1988 2007

We report a total of 156 cetacean sightings made in the northern Adriatic Sea between 1988 and 2007. Con firmed identifications (n 97) involved exclusively common bottlenose dolphins Tursiops truncatus. Encounter rates for this species, obtained between 2001 and 2006 during visual cetacean surveys, ranged between 0.42 and 1.67 groups per 100 km of navigation, with no significant differences among years if a consistent methodology was used. Information provided by this study contributes to setting environmental baselines and it can inform the design of surveys aimed to obtain absolute estimates of cetacean abundance in this part of the Adriatic