In this study, performed under the LifeWatchGreece infrastructure, are presented preliminary results from the digitization of biodiversity data from various sampling expeditions carried out from 1996 to 1999. The main purposes of the project were to examine the biodiversity of mäerl habitats in European seas, assess the anthropogenic impacts and develop conservation strategies for European mäerl beds. Twelve sampling sites were selected. Six of them were subjected to anthropogenic impacts and the other six represented pristine conditions as far as possible. Overall, 4127 records of marine biota were digitized belonging to phyla of the kingdoms Bacteria, Plantae, Chromista and Animalia.