Caves, overhangs and surge gullies in Pontic infralittoral rock
Quick facts
| Red List habitat type | code BLSA3.74 |
|---|---|
| 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
Caves and overhangs in the infralittoral zone are completely submerged at all states of the tide. Light conditions are generally poor which influences the species that can occur in these situations. As a result communities of sciaphillic algae, sponges and mussels are commonly present. Information on the biodiversity of sublittoral caves in the Black Sea is extremely fragmentary but some studies have been undertaken. e.g. describing the dominating sponge communities in the shallow semi-submerged karst caves on the Tarhankut peninsula, Crimea.
The habitat includes a range of situations including: vertical walls under overhangs, semi-dark tunnels and walls and floors of semi dark tunnels. Each of these may contain its own unique diagnostic communities which are also influenced by the rock type and the size of the cave - most semi-submerged caves from the Tarkhankut peninsula are small (5-10m) but the longest Kapchik-2 is 250m in length. Studies of caves in the Tarkhankut peninsula indicate a faunal zonation with depth into the cave.
The habitat is dominated by filter feeders in the surge gullies, robust species able to cope with the heavy wave action.
Indicators of quality:
Both biotic and abiotic indicators have been used to describe marine habitat quality. These include; the presence of characteristic species and those which are sensitive to the pressures the habitat may face, water quality parameters, levels of exposure to particular pressure as well as 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
| 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
- Pollution
- Nutrient enrichment (N, P, organic matter)
- Input of contaminants (synthetic substances, non-synthetic substances, radionuclides) - diffuse sources, point sources, acute events
- Marine macro-pollution (i.e. plastic bags, styrofoam)
- Natural System modifications
- Siltation rate changes, dumping, depositing of dredged deposits
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 marine habitats
- Other marine-related measures
- Measures related to spatial planning
- Establish protected areas/sites
- Legal protection of habitats and species
- Measures related to urban areas, industry, energy and transport
- Other measures
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) |
|---|---|---|---|---|
| Black Sea | Present | Unknown | Unknown | Unknown |
| Sea of Marmara |
Extent of Occurrence, Area of Occupancy and habitat area
| Extent of Occurrence (EOO) (Km2) | Area of Occupancy (AOO) | Current estimated Total Area | Comment | |
|---|---|---|---|---|
| EU28 | Unknown | Unknown | Unknown | The habitat is known to occur in the Black Sea but there is insufficient data to accurately calculate EOO and AOO. |
| EU28+ | Unknown | Unknown | The habitat is known to occur in the Black Sea but there is insufficient data to accurately calculate EOO and AOO. |
EOO = the area (km2) of the envelope around all occurrences of a habitat (calculated by a minimum convex polygon).
