The number of non-indigenous species which are newly introduced via human activity into the wild, per assessment period (6 years), measured from the reference year as reported for the initial asessment under Article 8(1) of Directive 2008/56/EC, is minimised and where possible reduced to zero. The threshold for good status in the Bulgarian Black Sea are as follows: BLK-BG-D2C1_NewNIS (coastal waters) = 1 BLK-BG-D2C1_NewNIS (shelf) = 0 BLK-BG-D2C1_NewNIS (open sea) = 0

Abundance and spatial distribution of established non-indigenous species, particularly of invasive species, contributing significantly to adverse effects on particular species groups or broad habitat types. Thresholds for good status in the Bulgarian Black Sea are as follows: BLK-BG-D2C2_ML_BIOM < 4 г/м3

Proportion of the species group or spatial extent of the broad habitat type which is adversely altered due to non-indigenous species, particularly invasive non-indigenous species. In the Bulgarian Black Sea a threshold is defined for the proportion of bivalves to invasive predatore Rapana venosa biomass: BLK-BG-D2C3_BV/RV_RATIO ≥ 10