AB.E1 Baltic aphotic shell gravel characterized by macroscopic epibenthic biotic structures


HELCOM RED LIST Biotope Expert Team

Textual description            

Baltic aphotic bottoms with at least 90 % coverage of shell gravel. Coverage of sessile macroscopic epifauna is ≥10%.

Physical environment       

Substrate is shell gravel. Appears mostly in high energy exposure areas.

Characteristic species        

Mytilus spp., Modiolus modiolus,Ciona intestinalis, Balanidae, Bryozoa

Mapping advise (habitat delineation, identification, similar types)             

Coverage of sessile macroscopic epifauna is ≥10%.

Geographic range               

Southern part of Baltic Sea, the Sound, Kattegat

Anthropogenic threats     

Increase in atmospheric CO2 (Ocean acidification)

Correspondence with other classification systems               

HELCOM 1998:
2.6 Shell gravel bottoms

2.6.1 Aphotic zone

HELCOM 2007:

Shell gravel bottoms

  • habitat under threat and/or in decline in all areas of occurrenc: The Southern Baltic Proper, The Gulf of Gdansk, Bay of Mecklenburg, Kiel Bay, Little Belt, Great Belt, The Sound, Kattegat

EUNIS 2012:

A5 Sublittoral sediment

A5.1 Sublittoral coarse sediment

A5.11 Infralittoral coarse sediment in low or reduced salinity