Distribution of Circalittoral Faunal Turfs (CFTs)

Global and European perspectives

Distribution within SAC sites

Global and European perspectives

CFT communities occur world-wide, and have much in common in that a major component of the fauna is comprised of coelenterates. In the tropics CFTs on rock substrata are uncommon, because the original rock surface, at least down to a depth of over 60 metres, is generally covered with stony scleractinian corals. Nevertheless the other components of the community - sponges, hydroids, anemones, soft coral, fan corals, serpulids, bryozoans and tunicates - are similar to those found in temperate CFTs.

In temperate regions the hard scleractinian corals are reduced to a very minor role, consisting mainly of small solitary polyps (nevertheless still of considerable conservation and biodiversity interest). The rest of the fauna, with the abundance of soft corals, makes it an analogy of a tropical reef community. The deep sea Lophelia reefs provide the only real temperate equivalent of a coral reef. CFTs occur throughout Europe in abundance. They are important in the Mediterranean, and equally so in Scandinavia where there are very well developed deep sheltered reefs in the fjords.

Distribution within SAC sites

CFT communities will be found in those SAC sites wherever rock substratum extends substantially below ELWS, and will be best developed where the rock extends to well below the depths supporting profuse algal growth (10 m or more). The more striking CFT communities typically occur where wave action and/or tidal currents generate substantial (though not excessively vigorous) water movement (see section II.D). Nevertheless there are very sheltered situations where rich and diverse CFT communities can occur, given the absence of sedimentation, and these less-typical communities are often of considerable conservation interest. Thus a general knowledge of the marine topography will indicate where CFTs are likely to occur. The rocky coastlines of Papa Stour or the Llyn Peninsula will provide widespread opportunities, whilst the Solway Firth or Morecambe Bay have limited potential as CFT sites. However, where candidate SAC sites contain small areas of CFT communities amongst predominantly different biotopes, then these small areas can, if of adequate quality, provide particularly valuable resources which may well come under substantial pressure. Where appropriate they should be highlighted, and managed suitably.

Figure 3 shows the locations of the ‘candidate’ and ‘possible’ marine SAC sites - those with important CFT biotopes are shown in Figure 5. The twelve demonstration Marine SAC sites are shown in Figure 4, where they are divided into three categories according to the status of their CFT biotopes.

‘Reefs’ listed as an Annex I habitat feature for site selection, CFTs a major feature.

CFTs present in quantity, but not a selection feature.

CFTs absent, or present to only a minor extent.

The occurrence of CFTs in each of the demonstration SACs, grouped according to these three categories, is outlined below.

SACs in which CFTs are a feature for site selection

SACs in which CFTs are present in quantity

SACs where CFTs are absent or unimportant

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