Natural England - Fragile sponge and anthozoan communities on subtidal rocky habitats

Fragile sponge and anthozoan communities on subtidal rocky habitats

Large colonies of sponges, anemones and sea-fans growing on rocks in shallow water.

Fragile sponge and anthazoan communities on subtidal rocky habitats © Keith Hiscock

Fragile sponge © Keith Hiscock

Anthozoans are a group of soft animals with feathery tentacles, which includes soft corals, sea-fans, cup corals and anemones. Members of this group can be found together with branching sponges on steeply sloping bedrock or large boulders in depths from about 50m to just below low tide.

These sponge and anthozoan communities require sufficient water movement to bring a ready supply of food but not too much, as they are vulnerable to breakage. As a result, they are found on shores which are exposed to moderate or strong waves and possibly quite strong tidal currents, but only in areas of those shores where there is some local shelter from the full force of the waves and tides.

The communities of animals that live here are dominated by large, slow growing species such as branching sponges and sea-fans. 

Beneath these large colonies of animals, there is a rich under-storey of sea squirts, including the lightbulb sea squirt, and sea mats, such as the ross coral, with it’s hard, orange, crinkly ‘petals’.

Brief description of European distribution

This community is present around England’s south-west peninsula from west Dorset to Lundy Island, and also off the south-east coast of Ireland.

Conservation status / need

UKBAP Priority Habitat

Habitats Directive Annex I: Reefs

Further information sources

UK List of Priority Habitatsexternal link (UKBAP)

Interesting fact

Sponges have changed little in the past 600 million years, and are found throughout the fossil record.