Epifaunal communities on Baltic circalittoral rock and mixed substrata (predominantly hard)
_(1).jpg "HELCOM RED LIST Biotope Expert Team 2013 and Baltic Sea Working Group for the European Red List of Habitats 2014 and 2015.")
_(2).jpg "HELCOM RED LIST Biotope Expert Team 2013 and Baltic Sea Working Group for the European Red List of Habitats 2014 and 2015.")
Quick facts
| Red List habitat type | code BAL42 |
|---|---|
| Threat status | |
| Europe | Near Threatened |
| EU | Near Threatened |
| Relation to |
|
| Source | European Red List habitat factsheet |
| European Red List of habitats reports | |
| European Red List of habitats (Excel table) |
Summary
This is a Baltic Sea benthic habitat in the aphotic zone where at least 90% of the substrate is rock, boulders or stones as well as on mixed (predominantly hard) substrates where the percentage of rock is between 10-90% according to the HELCOM HUB classification. The HELCOM HUB identifies 14 different biotopes associated with the habitat. In each case the dominate species or species group (in the biotope title) constitutes at least 50% of the biomass. These are: epibenthic bivalves, chordates, cnidarians, bryozoans, crustaceans and sponges.
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. The amount of sediment covering the hard surfaces and the diversity, abundance and biomass of associated fauna are potential quality indicators for this habitat.
Threat status
Synthesis of Red List assessment
The overall assessment for this EUNIS level 4 habitat has been based on the HELCOM (2013) assessments for the associated HELCOM HUB biotopes. Draft assessments were derived using a weighted approach whereby the HELCOM assessment outcomes were assigned a score. This was averaged across the relevant biotopes. The outcomes were reviewed by Baltic experts to reach a final conclusion. HELCOM (2013) assessed eight of the associated biotopes as Near Threatened (A1), and eight as Least Concern (A1). Two were not evaluated. Given the past and predicted future declines in extent of this habitat, current expert assessment is that it should be assessed as Near Threatened (A1) for both the EU 28 and EU 28+.
| EU | |
| Red List Category | Red List Criteria |
| Near Threatened | A1 |
| Europe | |
| Red List Category | Red List Criteria |
| Near Threatened | A1 |
Confidence in the assessment
Pressures and threats
- Mining, extraction of materials and energy production
- Mining and quarrying
- Sand and gravel extraction
- Exploration and extraction of oil or gas
- Biological resource use other than agriculture & forestry
- Fishing and harvesting aquatic resources
- Professional active fishing
- Benthic dredging
- Pollution
- Pollution to surface waters (limnic, terrestrial, marine & brackish)
- Nutrient enrichment (N, P, organic matter)
- Input of contaminants (synthetic substances, non-synthetic substances, radionuclides) - diffuse sources, point sources, acute events
Habitat restoration potential
Trends in extent |
|
Average current trend in quantity |
|
Decreasing  |
Decreasing |
| 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 wetland, freshwater and coastal habitats
- Restoring/Improving water quality
- Measures related to spatial planning
- Establish protected areas/sites
- 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) |
|---|---|---|---|---|
| Baltic Proper | Present | Unknown | Unknown | Decreasing |
| Belt Sea | ||||
| Gulf of Bothnia | ||||
| Gulf of Finland | ||||
| Gulf of Riga | ||||
| The Sound |
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 | Unknown | Unknown | This habitat is present in all the Baltic sub-basins however there is insufficient information for accurate calculation of EOO and AOO. |
| EU28+ | Unknown | Unknown | This habitat is present in all the Baltic sub-basins however 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).
