Based on the example of wintering waterbirds in the Baltic Sea, we show a method that is useful in setting priorities for species management. The Value Factor (VF) shows which species in the region are the most valuable and on which ones conservation measures need to focus. Every year 4,400,000 waterbirds winter in the Baltic. Among which the highest priority species are velvet scoter Melanitta fusca (VS, VF=153) and long-tailed duck Clangula hyemalis (LTD, VF=204): 74% and 40%, respectively, of the world populations and over 90% of the EU populations of both species spend the winter there. Management plans (MP) regulating the protection of marine Natura 2000 sites (MPA) and dedicated to the protection of VS and LTD have been implemented in 65% and 51%, respectively, of MPAs in the Baltic. Poland, a key country for the survival of these species, has not implemented a single MP despite the existence of documentation confirming their crucial importance for seaducks, and on the pressures occurring there. We suggest using the VF concept to define priority species. On this basis, it will be possible to identify gaps in the protection of the most seriously threatened species and implement conservation measures in the most appropriate sites