Even though no GES indicators have been agreed regarding Harbour Porpoise, the Eastern Baltic population of Harbour Porpoise is on the HELCOM Red List as critically endangered (CR) and the Wester Baltic population as vulnerable (VU). It is therefore quite clear that whatever GES indicators are eventually adopted, the current status of the species does not correspond to good environmental status. Since the Harbour Porpoise is a species that uses large tracts of the sea as its habitat, conservation measures by a single state are highly unlikely to be effective in the current situation of the species. Consequently, although Poland in its updated PoM has adopted measures dedicated to the conservation of the Harbour Porpoise, these measures on their own will not solve the problem. Other Baltic Sea States (Denmark, Estonia, Finland, Germany, Latvia, Lithuania, Russia, Sweden) and/or the European Union should put in place similar or complimentary measures.

After decades of almost complete absence, the Grey Seal has become a regular presence on the Polish coast. In recent years, the haul-out site at the mouth of the Vistula river has been hosting well over 200 seals each spring. However, births of young seals are very rare. It is thought that disturbance by humans may be a major factor contributing to lack of reproductive success. The updated PoM includes a measure consisting in the establishment of a protection zone around the houl-out site in order to remedy the situation. However, even if the measure proves to be a success, it will most probably take longer than until 2027 for the colony to reach reproduction rates coressponding to GES.