Pontic infralittoral sands and muddy sands with stable aggregations of perennial unattached macroalgae

This habitat occurs in infralittoral sands and muddy sands. It is most easily identified and defined by the presence of unattached forms of macroalgae, in particular the ball-like form of the red alga Phyllophora crispa var. sphaerica. The classic example of this habitat is the Small Phyllophora field (SPF) National Botanical Reserve, which lies in shallow water (less than 16 m) on sand with shells in Karkinitsky Bay, Ukraine and occupies some 300-400 km2. Smaller Phyllophora aggregations occur in shallow water (mostly 3-5 m) in Yagorlytsky, Dzharylgachsky, Tendrovsky and Yarylgachsky Bays, and near Cape Evpatoriysky.  Between 1938 and 1994, a shift in communities was observed in the SPF: the Phyllophora – oyster Ostrea edulis community was replaced by Mytilus galloprovincialis – Phyllophora, and the dominant species changed. From the 1970s, the most significant pressure was eutrophication which probably caused the greatest reductions in quantity and quality. After peaking in the 1980s, eutrophication has since reduced due to tighter controls on pollution in the catchment of the Danube and other rivers which enter the north-west Black Sea as well as industrial decline after the dissolution of the Soviet Union.

Indicators of quality:

Several elements of the “quality” of Phyllophora beds have been studied, including time series data comparing 3 patches of the SPF with regard to depth of occurrence, thickness of seaweed layers, biomass, and area covered, as well as the species composition of the benthic community.

Synthesis of Red List assessment

Confidence in the assessment

Pressures and threats