| Summary: | 34th European Cetacean Society Conference, O Grove, 16-20 April 2023 Information on cetacean distribution is needed at a range of scales, such as European, national, subregional or regional level. Providing detailed information at larger scales, with the highest possible spatial resolution, is essential to adequately assess and evaluate the impacts of human activities at the population or subpopulation level, as required by several legal instruments and international agreements (e.g., OSPAR or ASCOBANS). In this study, we modelled the distribution and relative abundance of common dolphin (Delphinus delphis), bottlenose dolphin (Tursiops truncatus), and pilot whale (Globicephala melas) in continental shelf waters of the Spanish North Atlantic waters, using a time series of 13 years of sightings collected on the PELACUS multipurpose survey in spring months by means of Distance Sampling methodology. Species distribution models were fitted using geographical and biological explanatory variables. The more than 20,000 km of effort, regularly distributed over the study area throughout the time series, provided more than 400 sightings of the species of interest. The three species showed interannual variability in distribution and relative abundance. These annual differences might reflect changes in their movement patterns due to the different timing of oceanographic and biological processes between years, as shown by the models and the variables analysed. The results prove the relevance of the continental shelf in southern Galicia (the Rias Baixas) as an area of importance for these species. The maps produced have several applications, including the identification of relevant areas for these species and, when combined with other data (e.g., fishing effort, underwater noise), quantitative risk analysis to different anthropogenic activities No
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