In 2022 and 2023, the CoastalWarming research team at CIBIO, in Portugal, surveyed the intertidal biodiversity of rocky shores along the North Atlantic coast, from Scotland to Morocco. The sampling protocol encompassed two approaches to identify and estimate the abundance of the main macrospecies typifying each shore: (i) quadrat sampling and (ii) SACFOR scaling. Some specimens were collected to confirm identifications with a magnifying lens.