AA.M1Q2 Baltic photic mixed substrate dominated by stable aggregations of unattached Fucus spp. (dwarf form)


HELCOM RED LIST Biotope Expert Team

Textual description 

Baltic bottoms in the photic zone with more than 10 %, but less than 90 % coverage of both hard and soft substrata. No perennial attached erect group has a coverage ≥ 10 %. Stable aggregations of unattached perennial vegetation covers at least 10 %, out of which Fucus spp.(dwarf form) constitutes at least 50 % of the biovolume.

Physical environment       

Salinity range: >4.5 psu; Exposure range: sheltered; Depth range: photic zone to about 5 meters.

Characteristic species  

Fucus vesiculosus dwarf form (synonym f.pygmaea)


Known from coasts of Sweden and Germany

Correspondence with other classification systems               

HELCOM 1998:

2.8 Mixed sediment bottoms

2.8.2 Sublittoral photic zone Dominated by macrophyte vegetation

EUNIS 2012:

A5 Sublittoral sediment

A5.5 Sublittoral macrophyte-dominated sediment


 Related Information

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

See the Biotope Information Sheet of AA.M1Q2