Faunal communities on variable salinity Atlantic circalittoral rock
.jpg "European Red List of Habitats 2016")
.jpg "European Red List of Habitats 2016")
Quick facts
| Red List habitat type | code NEAA4.25 |
|---|---|
| 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 type occurs on wave-sheltered, variable/reduced salinity bedrock and boulders, subject to moderately strong to weak tidal streams. There may be large growths of the brackish-tolerant sponge Halichondria bowerbanki. It is characterised by sponges tolerant of variable salinity, barnacles and a sparse hydroid and bryozoan turf. Especially where low salinity is frequently present, ‘groves’ of the peacock worm Sabella pavonina may be present. Beds of mussels, Mytilus edulis, may also be present but may be ephemeral.
Indicators of quality:
Both biotic and abiotic indicators have been used to describe marine habitat quality. These include: the presence of characteristic species as well as those which are sensitive to the pressures the habitat may face; water quality parameters; levels of exposure to particular pressure, and more integrated indices which describe habitat structure and function, such as trophic index, or successional stages of development in habitats that have a natural cycle of change over time.
There are no commonly agreed indicators of quality for this habitat, although particular parameters may have been set in certain situations e.g. protected features within Natura 2000 sites, where reference values have been determined and applied on a location-specific basis.
Threat status
Synthesis of Red List assessment
Although not considered likely to occur in many locations it is unlikely that the available data show its full distribution. It exceeds the threshold for threated status on the basis of a small range but there is a lack of information on trends. 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
- Fishing and harvesting aquatic resources
- Professional active fishing
- Demersal seining
- Pollution
- Pollution to surface waters (limnic, terrestrial, marine & brackish)
- Natural System modifications
- Human induced changes in hydraulic conditions
Habitat restoration potential
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 spatial planning
- Other marine-related measures
- Establish protected areas/sites
- Measures related to hunting, taking and fishing and species management
- Regulation/Management of fishery in marine and brackish systems
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) |
|---|---|---|---|---|
| Bay of Biscay and the Iberian Coast | Present | Unknown | Unknown | Unknown |
| Celtic Seas | ||||
| Greater North Sea | ||||
| Kattegat |
Extent of Occurrence, Area of Occupancy and habitat area
| Extent of Occurrence (EOO) (Km2) | Area of Occupancy (AOO) | Current estimated Total Area | Comment | |
|---|---|---|---|---|
| EU28 | 209,008 | unknown | Unknown | There is insufficient information for accurate calculation of EOO and AOO. |
| EU28+ | unknown | Unknown | There is insufficient information for accurate calculation of EOO and AOO. |
EOO = the area (km2) of the envelope around all occurrences of a habitat (calculated by a minimum convex polygon).
