AA.E2 Baltic photic shell gravel characterized by sparse macroscopic epibenthic biotic structures


HELCOM RED LIST Biotope Expert Team

Textual description

Baltic bottoms in the photic zone with at least 90 % coverage of shell gravel; coverage of macroscopic vegetation or sessile macroscopic epifauna is 0><10 %.

Physical environment

Salinity range: up to 5 psu; Exposure range: moderate to high; Depth range: photic zone

Characteristic species

Due to the large variety of interstitial space, inhabited by very specialized fauna, for example Amphioxus spp. (HELCOM 1998)

Mapping advise (habitat delineation, identification, similar types)

Photic zone areas consisting of dead mollusc shells or shell fragments. Coverage of macroscopic vegetation or sessile macroscopic epifauna is 0><10 %.

Geographic range

Up to the Quark in the North and to the 5 psu salinity gradient in the Eastern Gulf of Finland

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

A5.1 Sublittoral coarse sediment

A5.11 Infralittoral coarse sediment in low or reduced salinity

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