Abstract
The following conclusions were reached: The number of dolphins using the SAC continues to show interannual variability but remains stable in the long term. However, the recent reporting period has seen a decline in the number of dolphins and in the proportion of the total population using this area. In contrast, the number of dolphins and the proportion of the east coast population using Tayside & adjacent waters has increased. The population of dolphins on the east coast of Scotland is still increasing. Both the SAC and Tayside & adjacent waters area are used by >50% of the population in most years. Passive acoustic monitoring continues to show interannual variability in dolphins’ use of the SAC with a peak during summer months. However, one area was used to a similar extent during summer, autumn and winter. As the long-term trend in the number of dolphins using the SAC remains stable, the use of this protected area continues to be high, and the east coast population is increasing we recommend that the condition status is Favourable (maintained).