Description of biotope or habitat type
Hediste diversicolor and Streblospio shrubsolii in littoral gravelly sandy mud
Habitat (physical) description
|Salinity||Reduced (18-30ppt), Variable (18-35 ppt)|
|Wave exposure||Sheltered, Very sheltered, Extremely sheltered|
|Substratum||Gravelly sandy mud|
|Depth Band||Lower shore, Mid shore|
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.
Extremely sheltered gravelly sandy mud, subject to variable salinity, on the mid and lower shore. The infaunal community consists of the ragworm Hediste diversicolor, Pygospio elegans, Streblospio shrubsolii, and Ampharete grubei, as well as oligochaetes and Corophium volutator. There are often low densities of Scrobicularia plana. Given the low sample numbers for this biotope, more records are needed to confirm the characterising species list.
It is probable that there are broad transition areas between this biotope and the corresponding muddy sediment biotope Hed.Str. The boundaries may be very indistinct, with HedMx.Str present in patches of gravelly mud on areas of mudflat, where the main biotope is Hed.Str. This biotope has been found along edges of tidal channels in the upper Stour estuary, below its equivalent mud biotope.
|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|
|Hediste diversicolor||55||Super abundant||1719||81-100 %|
|Pygospio elegans||5||Common||279||41-60 %|
|Streblospio shrubsolii||14||Common||219||81-100 %|
|Ampharete grubei||3||Abundant||193||41-60 %|
|Corophium volutator||2||Frequent||39||61-80 %|