AA.B1E Baltic photic hard clay characterized by epibenthic bivalves


HELCOM RED LIST Biotope Expert Team

Textual description            

Baltic photic zone bottoms with at least 90 % coverage of hard clay. Sessile/semi-sessile epibenthic bivalves cover of at least 10 % of the seabed.

Physical environment       

Substrate is hard clay. Depth range: photic zone. Typically high energy exposure areas.

Characteristic species        

Mytilus spp.

Quality descriptors             

Diversity, abundance and biomass of fauna.

Geographic range              

Whole Baltic Sea

Anthropogenic threats     


Correspondence with other classification systems               

HELCOM 1998:

2.3 Hard clay bottoms

2.3.2 Sublittoral photic zone