The present study attempts to improve understanding of the patterns of seabird by-catch in the Ionian Sea and more specifically in the wider marine area of the Prefecture of Zakynthos Island, as well as to identify the main types of fishing gear responsible for by-catch, and to estimate the impact on local populations of seabird species listed in Annex I of the ‘Birds Directive’ 2009/147/EC (EU, 2009).