Description of biotope or habitat type
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Circalittoral faunal communities in variable salinity
Physical habitat description
| Salinity | Full (30-35 ppt) |
|---|---|
| Wave exposure | Sheltered, Very sheltered, Extremely sheltered |
| Tidal streams | Moderately strong (1-3 kn), Weak (>1 kn) |
| Substratum | Bedrock, cobbles |
| Zone | Circalittoral - lower, Circalittoral - upper |
| Depth Band | 0-5 m, 5-10 m, 10-20 m |
| Other Features |
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
Point data based on records in the UK Marine Recorder Snapshot. Predicted habitat extent is from UKSeaMap.
Description
This biotope complex occurs on wave-sheltered, variable salinity bedrock and cobbles, subject to moderately strong to weak tidal streams. This complex contains a suite of sponges able to tolerate the variable salinity conditions like Hymeniacidon perlevis, Suberites ficus, Halichondria panicea, Halichondria bowerbanki, Cliona celata and Leucosolenia botryoides. The barnacle Balanus crenatus is frequently recorded in this complex. A sparse hydroid/bryozoan turf composed primarily of Nemertesia antennina, Nemerteis ramosa, Plumularia setacea, Alcyonidium diaphanum and Crisularia plumosa is often recorded. Other species recorded are the ascidians Clavelina lepadiformis, Morchellium argus and Dendrodoa grossularia, the anemones Metridium senile and Sagartia troglodytes, the starfish Asterias rubens and the crab Carcinus maenas. Two biotopes have been identified within this complex: CuSpH (cushion sponges with hydroids) and HbowEud.
Situation
No situation data available.
Temporal variation
No temporal variation data available.
Characterising species
| Taxon | Relative importance of taxon for defining this community (%) | Typical abundance - SACFOR scale | % of core records where taxon was recorded |
|---|---|---|---|
| Balanus crenatus | 9 | Common | 41-60% |
| Clavelina lepadiformis | 8 | Frequent | 41-60% |
| Hymeniacidon perlevis | 8 | Frequent | 41-60% |
| Suberites ficus | 8 | Frequent | 61-80% |
| Halichondria panicea | 6 | Frequent | 41-60% |
| Halichondria bowerbanki | 5 | Frequent | 41-60% |
| Nemertesia antennina | 5 | Frequent | 41-60% |
| Asterias rubens | 4 | Occasional | 41-60% |
| Carcinus maenas | 4 | Occasional | 41-60% |
| Plumularia setacea | 4 | Occasional | 41-60% |
| Metridium senile | 3 | Occasional | 21-40% |
| Crisularia plumosa | 2 | Occasional | 21-40% |
| Morchellium argus | 2 | Occasional | 21-40% |
| Nemertesia ramosa | 2 | Frequent | 21-40% |
| Alcyonidium diaphanum | 1 | Occasional | 21-40% |
| Cliona celata | 1 | Occasional | 21-40% |
| Dendrodoa grossularia | 1 | Occasional | 21-40% |
| Leucosolenia botryoides | 1 | Frequent | 21-40% |
| Sagartia troglodytes | 1 | Occasional | 21-40% |
Similar biotopes or habitat types
Not applicable or unknown.