Underwater landscapes of Peter the Great Bay present major interest for observation and photography of both individual organisms and communities. The Bay has the largest specific diversity of floor animals in Russia. Coelenterata (Actinia, medusas, and Ctenophora), mollusks (CephalopodaЧthe octopus and squids), echinoderms (sea urchins, starfish, Ophiuroidae and holothurians), ascidia and numerous fish present special interest. Most of them occur on rocky soils, underwater cliffs, banks (Ivanov, Boisman, Bonsdorf, Furnovo and De Livron), often covered with a motley solid carpet of algae, actinia and mollusks. At deeper horizons in springtime and fall, you can come across octopuses. On sandy soil, you can also come across dark red and gray flat and cordiform sea urchins and bright starfish. The various algae are diverse, too.
    Deeper than 20 m, on rocky-sandy soil, large macrobenthos species disappear almost totally. However, at these depths, on the boulder heap boundary, if you look around sufficiently well, you can come across large octopuses. Boulders also abound with Actinia.  On the sidewalls of boulders, they form spots of up to 3-4 sq. m in area with 100% projective soil cover. Mussel druses also occur in the form of occasional spots among Actinia.  Black sea urchins (5-6 specimens/sq. m) Patiria starfish (2-3 specimens/sq.m), single gray urchins, rare trepangs and Swift pectens, and numerous sea limpets were noted on rock pinnacles.

A. TIURIN, Cand. Sci (Biology).