AA.E1C4 Baltic photic shell gravel dominated by kelp


HELCOM RED LIST Biotope Expert Team

Textual description            

Baltic bottoms in the photic zone with at least 90 % coverage of shell gravel. Perennial attached algae cover at least 10 % of the seabed, and more than other perennial attached erect groups. Out of the perennial attached algae, kelp constitutes at least 50 % of the biovolume.

Physical environment       

Salinity range: <11 psu; Exposure range: moderate to high; Depth range: photic zone

Characteristic species        

Saccharina latissima, Laminaria digitata, Laminaria hyperboria

Mapping advise (habitat delineation, identification, similar types)             

Photic zone areas consisting of dead mollusc shells or shell fragments.

Geographic range               

South-western Baltic Sea, the Sound

Anthropogenic threats     


Correspondence with other classification systems               

HELCOM 1998:

2.6 Shell gravel bottoms

2.6.2 Sublittoral photic zone

HELCOM 2007:

Shell gravel bottoms

  • habitat under threat and/or in decline in all areas of occurrence : 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

A5.5 Sublittoral macrophyte-dominated sediment

A5.52 Kelp and seaweed communities on sublittoral sediment


 Related information

This biotope has been listed as Near Threatened (NT) in the HELCOM Red List of Baltic Sea biotopes and habitats.

See the Biotope Information Sheet of AA.E1C4