Description of biotope or habitat type
To understand more about what this page is describing, see How to use the classification. See also How to cite.
Polychaete/amphipod-dominated fine sand shores
Physical habitat description
| Salinity | Full (30-35 ppt), Variable (18-35 ppt) |
|---|---|
| Wave exposure | Moderately exposed, Sheltered |
| Tidal streams | |
| Substratum | Sand |
| Zone | |
| Depth Band | Lower shore, Mid shore, Strandline, Upper shore |
| 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'
Point data based on records in the UK Marine Recorder Snapshot.
Description
Shores of clean, medium to fine and very fine sand, with no coarse sand, gravel or mud present. Shells and stones may occasionally be present on the surface. The sand may be duned or rippled as a result of wave action or tidal currents. The degree of drying between tides is limited, and the sediment usually remains damp throughout the tidal cycle. Typically, no anoxic layer is present. Fine sand shores support a range of species including amphipods and polychaetes. On the lower shore, and where sediments are stable, bivalves such as Macomangulus tenuis may be present in large numbers. An exceptionally rich fine sand community has been recorded from very sheltered reduced salinity shores in Poole Harbour. Species recorded include Phyllodoce maculata, Hediste diversicolor, Scoloplos armiger, Pygospio elegans, Tharyx killariensis, oligochaetes, Gammarus locusta, Peringia ulvae, Cerastoderma edule and Mya truncata.
Situation
Fine sand communities may be present throughout the intertidal zone on moderately exposed beaches, or they may be present on the lower parts of the shore with mobile sand communities present along the upper shore. A strandline of talitrid amphipods (Tal) typically develops at the top of the shore where decaying seaweed accumulates.
Temporal variation
Fine sand shores may show seasonal changes, with sediment accretion during calm summer periods and beach erosion during more stormy winter months. There may be a change in sediment particle size structure, with finer sediment grains washed out during winter months, leaving behind coarser sediments.
Characterising species
| 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 |
|---|---|---|---|---|
| Macomangulus tenuis | 57 | Abundant | 313 | 61-80% |
| Nephtys cirrosa | 8 | Common | 42 | 41-60% |
| Paraonis fulgens | 5 | Abundant | 72 | 21-40% |
| Bathyporeia pilosa | 3 | Common | 260 | 21-40% |
| Spio filicornis | 3 | Common | 60 | 21-40% |
| Nemertea | 2 | 19 | 41-60% | |
| Pygospio elegans | 2 | Frequent | 69 | 21-40% |
| Pontocrates arenarius | 1 | Frequent | 30 | 21-40% |
| Scoloplos armiger | 1 | Common | 19 | 21-40% |
| Spiophanes bombyx | 1 | Common | 20 | 21-40% |
Similar biotopes or habitat types
Not applicable or unknown.