Ballast Water Management Convention (BWMC) has entered into force in September 2017, requiring all ships in international traffic to manage their ballast water and sediments to a certain standard. BWMC Regulation A-4 gives Contracting Parties the right to grant exemptions from ballast water treatment. An exemption cannot be granted if there is a risk for the species, which is on Target Species (TS) list, to be spread by ballast water.

According to the IMO (2007) definition, Target Species are those identified by a Party that meet specific criteria indicating that they may impair or damage the environment, human health, property or resources and are defined for a specific port, State or biogeographic region. The TS lists are needed for taking decision whether ballast water management exemption can be granted on ship voyages between selected ports or within a particular marine area.

COMPLETE will result in recommendation for an improved and up-to-date risk assessment for BWMC A-4 exemptions, fully reflecting the Baltic Sea specifics (salinity gradient, differences in climatic conditions etc.). Using the existing Target Species list, which was prepared in the framework of HELCOM-OSPAR Joint Harmonized Procedure for BWMC A-4 exemptions, COMPLETE will review and update selection criteria based on international expertise and local knowledge supported by the integrated Baltic Sea non-indigenous species (NIS) monitoring programme.