Habitat requirements

Habitat factor Range of conditions
Salinity Full
Wave exposure Exposed, moderately exposed
Substratum Bedrock; cobbles; boulders; pebbles; sand

Sabellaria alveolata requires a hard substratum on which to form and these areas must have a good supply of suspended coarse sediment. S .alveolata reefs can form on a range of substrata from pebble to bedrock (Cunningham et al. 1984). Reefs therefore commonly form on areas of rock or boulders surrounded by sand.

Height band Mid shore, Lower shore

Reefs form mainly on the bottom third or so of the shoreline and in the shallow subtidal. Reefs have been recorded subtidally in the Severn Estuary and have been assigned a new MNCR biotope code – SalvMx (Moore et al. 1998)

Zone Eulittoral-mid, Eulittoral-lower
Temperature Gruet (1982) reported that growth of S. alveolata is severely restricted below 5oC. Crisp (1964) noted severe losses of S. alveolata due to the severe winter of 1962-63, especially in south and north Wales, and in Lyme Bay where some colonies were depleted by half and others lost completely. Survival was best at lower shore levels.
Water quality A supply of suspended coarse sediment is a requirement for the development of reefs, but the species has been reported to penetrate into areas such as the Severn Estuary where finer suspended sediments occur (Cunningham et al. 1984). Suspended sediment supply is affected by both the local availability of sediment and the amount of water movement for its suspension.

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