Ten Random Forest models were fitted in order to characterise the environmental niche and to predict the potential spatial distribution of Zostera marina along the French western seaboard. 3 rasters are provided: 1) Habitat suitability index (values ranging from 0 to 1 when conditions are estimated to be optimal), 2) standard deviation around the mean habitat suitability index, and 3) binary suitability estimates (0= not suitable, 1=suitable). These model estimates indicate areas where the species may occur and are overall consistent with field observations but note that these maps are model-based and do not correspond to actual field observations.