The Belgian MSFD monitoring programme ‘Biodiversity - seabed habitats’ aims at assessing the following ETs: • ET7 : The spatial extent and distribution of the EUNIS level 3 habitats (sandy mud to mud, muddy sands to sands and coarse grained sediments), as well as that of gravel beds fluctuate - relative to the reference state as described in Initial Assessment - within a margin limited to the accuracy of the current distribution maps • ET10: The Ecological Quality Ratio as determined by BEQI, indicative for benthic ecosystem structure and quality, has a minimum value of 0,60 in each of the habitat types • ET11: Positive trend in median adult density (or frequency of occurrence) of at least one species within the long-lived and/or slowly reproducing and key engineering benthic species groups in both mud to muddy sands and pure fine to coarse sands • ET12: Spring median benthic bioturbation potential (BPc) in the Abra alba habitat type is higher than 100 • ET13: Positive trend in median colony/body size of the sessile, long-lived and/or larger benthic species Buccinum undatum, Mytilus edulis, Flustra foliacea, Haliclona oculata and Alcyonium digitatum • ET14 – Positive trend in frequency of occurrence and median adult density of at least half of the key and long-lived species Ostrea edulis, Sabellaria spinulosa, Mytilus edulis, Buccinum undatum, Haliclona oculata, Alcyonium digitatum and Alcyonidium spp • ET15 – No loss or positive trend in species richness within all key hard substrate taxa, i.e. Porifera, Cnidaria, Bryozoa, Polychaeta, Malacostraca, Maxillopoda, Gastropoda, Bivalvia, Echinodermata and Ascidiacea • ET16 – Decreasing relative frequency of occurrence of damaged Asterias rubens (2+ cm arm length) and tube clusters of Pomatoceros triqueter, indicative for physical disturbance of the bottom (= pressure indicator), as to enhance natural development of the gravel bed ecosystem (= desired state) • ET17: For each of the scavenging seabirds species, are the mean densities over 5 consecutive years not below the minimum defined by the Birds Directive favourable conservation status Six sub-programmes can be discerned: • ANSBE-D1, 4, 6 Seabed-SP5 (delivering data to assess ET7), targeting a full-coverage seabed and transect seabed mapping of selected areas at EUNIS level 3; • ANSBE-D1, 4, 6 Seabed-SP6 (delivering data to assess ET10), targeting the quantification of a composite index based on density, biomass, species richness and species composition of the macrobenthos at selected stations in the BPNS; • ANSBE-D1, 4, 6 Seabed-SP7 (delivering data to assess ET11), targeting the quantification of long-lived and key engineering benthic species density at selected stations in the BPNS; • ANSBE-D1, 4, 6 Seabed-SP8 (delivering data to assess ET12), targeting the quantification of the macrobenthic community bioturbation potential at selected stations in the BPNS; • ANSBE-D1, 4, 6 Seabed-SP9 (delivering data to assess ET13 to 16), targeting body/colony size of characteristic hard substrate species, frequency of occurrence and densities in a non-bottom fisheries-impacted, a low impacted and regular fisheries-impacted area; • ANSBE-D1, 4, 6 Seabed-SP10 (delivering data to assess ET17), targeting multibeam bathymetry and backscatter measurements in combination with visual observations and seabed sampling in a gravel bed in the Hinder Banks region and a gravel bed in the Flemish Banks region