Habitat requirements

Habitat factor Range of conditions
Salinity Full
Wave exposure Moderately exposed
Tidal streams Moderately strong, Weak
Substratum Bedrock; boulders, cobbles, mixed substrata; mixed sediment

Sabellaria spinulosa reefs or crusts will form on hard substratum but this does not preclude their formation from other substrata (Hiscock 1991). Rees & Dare (1993) describe habitat preference as being typically on shell (especially oyster valves), sandy gravel or rocky substrates with moderate tidal flow. Larsonneur (1994) reported Sabellaria spinulosa-dominated communities present on rock/pebble bottoms in the Bay of Mont St. Michael. It is likely that stability of the reefs is to some degree a function of the stability of the substratum. The more transient crusts probably occur principally on relatively unstable substrata, while longer-lasting reefs could be limited to more stable substrata.

Zone Circalittoral
Depth range 10-30 m (CSab); 30->50 m (SspiMx)

Dense reefs reported in the Bristol Channel were found at a depth of 41m (George & Warwick 1985), while recently discovered reefs off the north Norfolk coast were found at 15-25 m (Foster-Smith et al., in prep. February 1998).

Temperature Specific information on temperature tolerance for this species is not available. However, its widespread distribution, from at least north of the Shetlands to the Mediterranean Sea, together with its predominantly subtidal habitat means that Sabellaria spinulosa is likely to be much less sensitive to temperature changes than the intertidal Sabellaria alveolata, which has been shown to be severely affected by low winter temperatures. Crisp (1964) found that Sabellaria spinulosa was less affected by the cold winter of 1963 than Sabellaria alveolata, which experienced many mortalities.
Water quality Sabellaria spinulosa requires suspended sand grains in order to form its tubes; reef communities therefore only occur in very turbid areas where sand is placed into suspension by water movement. The relative importance of tidal versus wave- induced movements is unclear. Studies in relation to sewage and other pollution suggest this species is not particularly sensitive to changes in water quality. However, this may not be the case for associated biota.

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