Along the Croatian Adriatic coast, the Common Tern (Sterna hirundo) breeds on small, sparsely vegetated rocky islets or artificial structures, usually in small colonies of 5-40 pairs. We monitored breeding success at four colonies in the Northern and Central Adriatic from 2021 to 2023 through regular visits and camera traps (in one colony for two years). In 2023 we used GPS loggers to track four males and five females from two colonies in the North and Central Adriatic to study their foraging range. Terns were mainly foraging along the coast or in the channel between the islands and the mainland. The mean daily maximum distance from the colony was 13.9 km, with no significant differences between the sexes. These distances are greater than for Common Terns from freshwater sites in Croatia and the German Wadden Sea. The birds most actively foraged during the late afternoon. As along the east Adriatic coast, diurnal winds increase in the mid-day and calm down towards the evening, this foraging dynamics could be the result of birds avoiding foraging among waves. Tracking studies with a finer temporal scale and detailed spatial and temporal data on wind and tidal dynamics are needed to understand the environmental factors that affect the foraging dynamics of Adriatic terns. Although freshwater lakes were within foraging range, no tracked terns were recorded foraging at freshwater sites. The average daily colony attendance (ratio of GPS locations within a 200 m buffer of the colony) was 0.47, significantly lower than in the freshwater populations. Daily nest attendance was higher for females (males 0.41, females 0.65). The clutch size was between 2.1 and 2.8 eggs per colony per year. Replacement clutches were common, with no significant difference in the number of eggs between first and replacement clutches. Breeding success was low in all colonies in all years (<0.5 chicks/nest). Disturbance by fishermen and tourists was identified as the main threat. Slightly larger breeding success was observed on more remote islands.