Red List habitat classification > RL - Marine habitats > RLBLS - Black Sea > BLSA5.5w Seagrass meadows in Pontic lower infralittoral sands

Seagrass meadows in Pontic lower infralittoral sands

Quick facts

Red List habitat type code BLSA5.5w
Threat status
Europe Vulnerable
EU Endangered
Relation to
Source European Red List habitat factsheet
European Red List of habitats reports
European Red List of habitats (Excel table)


Seagrass beds are found on sandy and sandy-muddy bottoms in sheltered habitats with sufficient lighting. Maximum development is in the summer. The habitat occurs all around the Black Sea as small and fragmented meadows. Its distribution is well documented in Russia, Ukraine, Romania and Bulgaria, while for Turkey it is mostly unknown. Off the coast of Georgia sparse eelgrass meadows are known to occur at Cape Souk-Sou (after Cystoseira communities at a depth of 6-10 m), in the Gulf of Skurge at a depth of 4-6 m. This habitat contains communities in both the upper and lower infralittoral sands with different dominant eelgrass species:

The habitat occurs in the deeper infralittoral zone, most typically where the sediment is silty sand and in the 10 m depth range. The meadows are found in sea water with salinity varying between 11 and 19 psu. Six species of seagrass may be present in this habitat but Zostera marina is generally dominant. There are also algae living on the eelgrass blades, mostly red algae. Species diversity develops two peaks, one in spring and the other in autumn. Seasonal dynamics of the biomass and density are less pronounced due to the depth. The communities of Z. marina display greatest diversity in the Kerch Strait with its special hydrological and hydrochemical conditions.

Indicators of quality:

Leaf length, biomass, shoot density have all been identified has indicators of quality. However, thresholds have not been set and these can and will vary between countries.

Characteristic species
For full habitat description, please download the habitat factsheet.

Threat status

Synthesis of Red List assessment

Due to this habitats restricted distribution and continued decline this habitat has been assessed as Endangered in the EU 28. Due to the overall slight decline in quality, this habtitat has been assessed as Vulnerable in the EU 28+. The threat is plausible based on losses caused in the recent past and plans to continue coastal development and protection works in both the EU 28 and the EU 28+.
Red List Category Red List Criteria
Endangered B1b, B2b
Red List Category Red List Criteria
Vulnerable C/D1

Confidence in the assessment

Red List of habitat categories and criteria descriptions

Pressures and threats

  • Urbanisation, residential and commercial development
    • Other urbanisation, industrial and similar activities
  • Human intrusions and disturbances
    • Other human intrusions and disturbances
    • Trampling, overuse
  • Pollution
    • Nutrient enrichment (N, P, organic matter)

Habitat restoration potential

If only quality degradation occurs then it is possible to recover naturally within 50 years if pollution pressures are removed. In case of strong habitat fragmentation or loss of whole meadows recovery may take much longer or even never occur.

Trends in extent

Average current trend in quantity

Decreasing Decreasing
EU28 EU28+

Trends in quality

Average current trend in quality

Stable Decreasing
EU28 EU28+

Conservation and management needs

The habitat is a characteristic feature of several habitat types listed in Annex 1 of the Habitats Directive like 1130 Estuaries or 1160 Large shallow inlets and bays. Areas of this habitat in Romania and Bulgaria all occur in Natura 2000 protected areas. Around the Crimean region all seagrass meadows are included in a local Red List. Many meadows are present in marine reserves. Turkey has limited bait dredging to >30 m. Collection of Z. noltei is banned. Additional actions needed: Prohibit bait dredging over the entire Black Sea; Improve enforcement of MPAs; explore habitat restoration (i.e. translocation of sea grasses. This has yet to be tested in the Black Sea), improve water quality.

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


For each habitat a distribution map was produced from a wide variety of sources indicating known and potential occurrences of the habitat in 10x10 km grids within Europe. Occurrences in grid cells were given in two classes: actual distribution from relatively reliable sources (surveys, expert knowledge), and potential distribution based on models or less reliable indicators. Please download the fact sheet to see the map.

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 9,155 13 13,00 EOO and AOO have been calculated on the available data.
EU28+ 146 14,600 EOO and AOO have been calculated on the available data.
AOO = the area occupied by a habitat measured in number of 10x10 km grid cells.
EOO = the area (km2) of the envelope around all occurrences of a habitat (calculated by a minimum convex polygon).

Characteristic species

The full list of characteristic species and genus are available above from the Summary. The species available in the EUNIS database are shown here.
Algae Cystoseira barbata
Algae Gracilaria gracilis
Flowering Plants Zostera marina
Species scientific name English common name Species group
Cystoseira barbata Algae
Gracilaria gracilis Algae
Zostera marina Flowering Plants

Vegetation types

Relation to vegetation types (syntaxa)

Not available

Other classifications

Not available
European Environment Agency (EEA)
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