AA.E3X Baltic photic shell gravel characterized by mixed infaunal macrocommunity in coarse and well-sorted shells and shell fragments


HELCOM RED LIST Biotope Expert Team

Textual description            

Baltic photic bottoms with at least 90 % coverage of shell gravel. Macroscopic infauna present, no macrovegetation or epibenthic macrofauna. Dominant type of shell gravel fragments is coarse and well-sorted.

Physical environment       

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

Mapping advise (habitat delineation, identification, similar types)             

Only for biotopes occuring in Kattegat and the most southern parts of the Baltic Sea (Mytilus shell gravel in Northern Baltic Sea, should be classified AA.E1E1)

Geographic range               

Southern part of Baltic Sea

Anthropogenic threats     

Increase in atmospheric CO2 (Ocean acidification)

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

A5.1 Sublittoral coarse sediment

A5.11 Infralittoral coarse sediment in low or reduced salinity

A5.113 : Baltic shell gravel bottoms in the infralittoral photic zone