Description of biotope or habitat type
Capitella capitata and Tubificoides spp. in reduced salinity infralittoral muddy sediment
Habitat (physical) description
|Salinity||Reduced (18-30ppt), Variable (18-35 ppt)|
|Wave exposure||Moderately exposed, Sheltered, Extremely sheltered|
|Tidal streams||Strong (3-6 kn), Moderately strong (1-3 kn), Very weak (negligible)|
|Substratum||Cohesive muddy sediment, sandy mud|
|Depth Band||0-5 m, 5-10 m, 10-20 m|
|Other Features||Possible organic enrichment or physical disturbance|
Download comparative physical and biological data. The comparative tables enable a rapid comparison of the species composition and principal physical characteristics between a given set of biotopes.
- Records used to define the biotope (core records)
- Other records assigned to this biotope, marked as 'certain'
- Other records assigned to this biotope, marked as 'uncertain'
- Predicted extent of the level 3 (for sublittoral rock & deep sea) or 4 (for sublittoral sediment) habitat
Reduced or variable salinity muddy sediment characterised by the Capitella capitata species complex with a relatively low species richness. Large numbers of the oligochaetes Tubificoides spp. may be found in conjunction with C. capitata, along with other species such as Marenzellaria sp, Macoma balthica, Arenicola marina and Eteone longa. In some estuaries this biotope may also include high numbers of the polychaete Ophryotrocha. This biotope usually has a moderate organic content, and is found away from tidal channels in estuaries. The presence of dense Capitella has classically been associated with organically enriched and physically disturbed habitats in the marine environment (Warren 1977; Pearson & Rosenberg 1978) and areas of higher organic loads in estuaries will typically fall into the biotope Cap. Where Capitella is less abundant and accompanied by other typical estuarine species the dominance of Capitella may be associated with other natural factors including the occurrence of a competitive refuge for C. capitata in the reduced-salinity environment (Wolff 1973).
No situation data available.
No temporal data available.
|Taxon||Relative importance of taxon for defining this community (%)||Typical abundance - SACFOR scale||Typical abundance - (count per m2)||% of core records where taxon was recorded|
|Eteone longa||2||Common||6||21-40 %|
|Neanthes virens||1||5||1-20 %|
|Pygospio elegans||1||5||21-40 %|
|Capitella capitata||60||Frequent||119||81-100 %|
|Arenicola marina||3||6||21-40 %|
|Tubificoides benedii||10||Frequent||84||21-40 %|
|Corophium volutator||1||8||21-40 %|
|Macoma balthica||4||4||41-60 %|