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Marine Habitat Classification

Description of biotope or habitat type

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   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
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.

Distribution of habitat LS.LSa.FiSa Polychaete/amphipod-dominated fine sand shores

  • 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.


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.


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.

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