Fig. 1 Area where porpoises were exposed to boat disturbance. The red rectangle in the top left map indicates the location of the study area; coloured lines show the boat tracks on different dates during fieldwork. The country map was extracted using the “rnaturalearth” package for R (Massicotte & South, 2023). Bathymetry data were obtained from https://emodnet.ec.europa.eu/en/bathymetry.