Macaronesian communities of infralittoral algae moderately exposed to wave action
|Red List habitat type||code NEAA3.23|
|Source||European Red List habitat factsheet|
|European Red List of habitats reports|
|European Red List of habitats (Excel table)|
This habitat is characterised by the presence of many photophilic algae covering areas of bedrock and boulders. It occurs in the infralittoral zone in areas that are moderately exposed to wave action and currents.
In the case of the Azores - northern archipelago – four associations are recognized: one of the brown algae Colpomenia sinuosa, another one of the red genus Peyssonnelia, with P. rubra as most common species. The two other biotopes are mainly associated to brown macroalgae, such as Zonaria tournefortii – Dictyota spp. and Turf (calcareous and non calcareous) with Dictyota spp. and Stypocaulon scoparium / Halopteros filicina.
In the southern archipelagos: Madeira, Selvagem and Canary Islands the diversity of biotopes is much greater as is the variety of associated macroalgae. Where the articulated calcareous algae Ellisondia (Corallina) elongate is the characteristic species, there are also many associated epiphytes and small marine invertebrates. The brown foliose macroalgal biotope is characterised mainly by Lobophora variegata, with other dictyotales such as Zonaria tournefortii, Dictyota spp., Stypopopdium zonale as major elements.There is also an associated biotope composed by the green algae Pseudotetraspora marina), which has been spreading along areas of moderately exposed infralittoral rocks in the Canary Islands. The biotope characterised by Cymopolia barbata covers large shallow infralittoral rocks in locations with strong sunlight. In the eastern canarian archipelago, another conspicuous biotope is that of Padina pavonica, which is sometimes associated with Cladostephus spongiosus, Hypnea and Spyridia.
On horizontal rocky surfaces the red algae Lophocladia trichoclados may form nearly monospecific stands. Seasonal red algal of the genera Galaxaura, Dudresnaya, Liagora and Helminthocladia, are key elements of another conspicuous biotope, whereas the turf forming articulated calcareous algae Haliptilon, Jania and Amphiroa are widespread biotope in the Selvagem and Canary Islands.
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
- Urban and industrial waste management
- 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||501,455||86||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+||86||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).
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|