AA.A1C2 Baltic photic rock and boulders dominated by perennial non-filamentous  corticated red algae


HELCOM RED LIST Biotope Expert Team

Textual description            

Baltic bottoms in the photic zone with at least 90 % coverage of rock, boulders or stones of more than 63 mm in diameter. Perennial attached algae covers at least 10 % of the seabed, and more than other perennial attached erect groups. Out of the perennial attached algae, corticated red algal species constitute at least 50 % of the biovolume.

Physical environment       

Salinity range: >5 psu; Exposure range: all, more common in exposed areas; Depth range: photic zone usually from about 2 to 10 meters

Characteristic species        

Furcellaria lumbricalis

Quality descriptors             

Lower limit of vegetation, amount of epiphytic algae

Geographic range               

Baltic Sea up to the Quark in the North and central Gulf of Finland approximately to the Russian border in the east

Anthropogenic threats     


Correspondence with other classification systems               

HELCOM 1998: Sublittoral level soft rock bottoms dominated by macrophyte vegetation Sublittoral level stony bottoms dominated by macrophyte vegetation

EUNIS 2012:
A3.4 : Baltic exposed infralittoral rock
A3.5 : Baltic moderately exposed infralittoral rock
A3.6 : Baltic sheltered infralittoral rock