Circalittoral biogenic habitats in the Mediterranean - corralligenous bioconcretions
.jpg "European Red List of Habitats 2016")
.jpg "European Red List of Habitats 2016")
Quick facts
| Red List habitat type | code MEDA5.6y |
|---|---|
| Threat status | |
| Europe | Data Deficient |
| EU | Data Deficient |
| Relation to |
|
| Source | European Red List habitat factsheet |
| European Red List of habitats reports | |
| European Red List of habitats (Excel table) |
Summary
This habitat sometimes referred to as 'coral gardens' can be found on a variety of substrates and at depths ranging from 20 to 200 meters. The main characteristic is a relatively dense aggregation of colonies or individuals of one or more coral species but also coralline algae. For example, soft-bottom coral gardens may be dominated by solitary scleractinians and sea pens, whereas hard-bottom coral gardens are often dominated by gorgonians, and red or black corals. Red corals rarely occurs about 30m as they require reduced light levels.
Reef forming hard corals (e.g. Lophelia, Madrepora and Caryophylliidae), if present, occur only as small or scattered colonies and not as a dominating habitat component. The habitat can also include relatively large numbers of sponge species. Other commonly associated fauna include basket stars, brittle stars, crinoids, ascidians, molluscs, crustaceans and fish.
Indicators of quality:
Several indicators have been proposed to assess the health of coralligenous habitats based on the composition and abundance of species (biotic cover and conspicuous species richness), the percent cover of different benthic assemblages (encrusting calcified Rhodophyta, non-calcified encrusting algae and fauna, turf forming algae, and sediment), boring species marks, percent cover of each species and the percentage of necrosis, bryozoa percent cover, sludge percent cover and the builder species percent cover.
Threat status
Synthesis of Red List assessment
Infralittoral coralligenous habitats are known to be decreasing in quality and quanitity but there is a lack of quanitative data on trends for circalittoral corralligenous concretions. This habitat has therefore been assessed as Data Deficient for both the EU 28 and EU 28+.
| EU | |
| Red List Category | Red List Criteria |
| Data Deficient | - |
| Europe | |
| Red List Category | Red List Criteria |
| Data Deficient | - |
Confidence in the assessment
Pressures and threats
- Biological resource use other than agriculture & forestry
- Professional passive fishing
- Demersal longlining
- Professional active fishing
- Benthic or demersal trawling
- Benthic dredging
- Removal for collection purposes
- Pollution
- Marine water pollution
- Invasive, other problematic species and genes
- Invasive non-native species
- Natural System modifications
- Reduction or loss of specific habitat features
- Applied (industrial) destructive research
- Climate change
- Changes in abiotic conditions
- Changes in biotic conditions
Habitat restoration potential
Some site specific studies for selected species (Corallium rubrum, Gorgonacea) have provide insights on the potential to recover after fishing activities or due to natural disasters (storms) and invasion of non-native species but these results cannot be generalized to other sites or to other species.
Trends in extent |
|
Average current trend in quantity |
|
Unknown  |
Unknown |
| EU28 | EU28+ |
Trends in quality |
|
Average current trend in quality |
|
| Unknown |
Unknown |
| EU28 | EU28+ |
Conservation and management needs
List of conservation and management needs
- Measures related to marine habitats
- Other marine-related measures
- Measures related to spatial planning
- Establish protected areas/sites
- Establishing wilderness areas/allowing succession
- Legal protection of habitats and species
- Measures related to hunting, taking and fishing and species management
- Regulation/Management of fishery in marine and brackish systems
- Measures related to special resouce use
- Regulating/Managing exploitation of natural resources on sea
Distribution
Geographic occurrence and trends
| Seas | Present or presence uncertain | Current area of habitat (Km2) | Recent trend in quantity (last 50 years) | Recent trend in quality (last 50 years) |
|---|---|---|---|---|
| Adriatic Sea | Present | Unknown | Unknown | Unknown |
| Aegian-Levantine Sea | ||||
| Ionian Sea and the Central Mediterranean Sea | ||||
| Western Mediterranean Sea |
Extent of Occurrence, Area of Occupancy and habitat area
| Extent of Occurrence (EOO) (Km2) | Area of Occupancy (AOO) | Current estimated Total Area | Comment | |
|---|---|---|---|---|
| EU28 | >50,000 | >38 | 163 | This habitat is present in all the Mediterranean sub-basins. AOO figures recognised as an underestimate. |
| EU28+ | >43 | 178 | This habitat is present in all the Mediterranean sub-basins. AOO figures are known to be an underestimate. |
EOO = the area (km2) of the envelope around all occurrences of a habitat (calculated by a minimum convex polygon).
Characteristic species
Legal status
Relation to other habitat types mentioned in legal instruments
| Legal text | Annex | Name in legal text | Code in legal text |
Habitat type relationship |
More information |
|---|---|---|---|---|---|
| Council Directive 92/43/EEC of 21 May 1992 on the conservation of natural habitats and of wild fauna and flora - consolidated version 01/01/2007 | Annex I: natural habitat types of community interest whose conservation requires the designation of special areas of conservation | Reefs | 1170 | Narrower | http://ec.europa.eu/environm...rective/index_en.htm |
