MULTI-YEAR SUCCESSION OF BIOFOULING COMMUNITIES ON UNDERWATER ARTIFICIAL STRUCTURES IN THE APHOTIC ZONE OF THE SEA OF OKHOTSK

А 10-year succession of the fouling community inhabiting underwater manmade structures at a depth of 80–90 m was described using the materials from regular video surveys of the technical installations on the southwestern shelf of the Sea of Okhotsk. A general scheme of macrofouling community developmental stages in steps of 1–2 years has been compiled both for the intact community and for sites subjected to the single or multiple hydrodynamic cleaning. For each stage we visually estimated the projective cover of macrofouling and identified the characteristic dominant species down to the smallest possible taxon. The first two years of the intact community are characterized by low projective cover (up to 50%), in the third year and further there is a sharp increase in the abundance and diversity of macrofouling organisms. Barnacles Chirona evermanni, sponges Phakellia sp., bryozoans Securiflustra securifrons, and ascidians Boltenia ovifera were noted among the dominant species in the community older than two years. The early stages of restorative succession differ from the intact succession in terms of dominant species and developmental rates.