Macaronesian seaweed communities on moderate energy infralittoral rock
|Red List habitat type||code NEAA3.2x|
|Source||European Red List habitat factsheet|
|European Red List of habitats reports|
|European Red List of habitats (Excel table)|
This habitat occurs predominantly on moderately wave-exposed bedrock and boulders, that are subject to moderately strong to weak tidal streams. Two associated biotopes have been described in the Azores archipelago. The first is dominated by Codium elisabethae, Halopteris filicina and coralline crusts on moderate to sheltered bedrock. The second is characterised by dense patches of the green alga Caulerpa webbiana. This species was first reported in the Azores in 2002 and although not considered an invasive species in other parts of Macaronesia or the world it has many characteristics of such a species in the Azores.
In the southern Macaronesian archipelagos, a more diverse sub-set of habitats are recognised, such as that defined by Stypocaulon scoparium / Halopteris filicina (A3.2X3), more frequent in Azores and Madeira archipelagos and with fewer locations in Selvagem and the Canary Islands.
Other representative biotopes in the Canarian archipelago are barren grounds of the long spined sea urchin Diadema africanum (A3.2X4) or those constructed by other sea urchin species Arbacia lixula or Paracentrotus lividus on shallower infralittoral volcanic rocks (A3.2X5). Corynactis viridis defines another interesting biotope (A.3.2X6) mainly associated with sea urchins whereas different zooantids, such as Isaurus tuberculatus, Zoanthus spp. and Palythoa spp are characteristic elements of another biotope (A3.2X7) in hard bottoms.
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.
Synthesis of Red List assessment
This habitat has a large EOO and AOO, and therefore qualifies as Least Concern under criterion B. However the habitat is assessed as Data Deficient both at the EU 28 and EU 28+ levels because of the lack of information on its area and any trends in quantity and quality.
|Red List Category||Red List Criteria|
|Red List Category||Red List Criteria|
Confidence in the assessment
Pressures and threats
- Urbanisation, residential and commercial development
- Urbanised areas, human habitation
- Biological resource use other than agriculture & forestry
- Fishing and harvesting aquatic resources
- Pollution to surface waters (limnic, terrestrial, marine & brackish)
- Nutrient enrichment (N, P, organic matter)
- Marine water pollution
- Invasive, other problematic species and genes
- Invasive non-native species
Habitat restoration potential
Trends in extent
Average current trend in quantity
Trends in quality
Average current trend in quality
Conservation and management needs
List of conservation and management needs
- Measures related to wetland, freshwater and coastal habitats
- Restoring/Improving water quality
- Measures related to spatial planning
- Other marine-related measures
- Establish protected areas/sites
- Measures related to urban areas, industry, energy and transport
- Managing marine traffic
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)|
Extent of Occurrence, Area of Occupancy and habitat area
|Extent of Occurrence (EOO) (Km2)||Area of Occupancy (AOO)||Current estimated Total Area||Comment|
|EU28||725,661||178||Unknown||EOO and AOO have been calculated on the available data. Although this data set is known to be incomplete the figures exceed the thresholds for threatened status.|
|EU28+||178||Unknown||This habitat does not occur outside the EU28|
EOO = the area (km2) of the envelope around all occurrences of a habitat (calculated by a minimum convex polygon).
|Species scientific name||English common name||Species group|
Relation to other habitat types mentioned in legal instruments
|Legal text||Annex||Name in legal text||Code in legal text||
|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||Overlap||http://ec.europa.eu/environm...rective/index_en.htm|