Сотрудники ИПIEE RAS staff took part in an expedition to Paramushir IslandЭЭ РАН приняли участие в экспедиции на острове Парамушир

Fig. 1. Members of the Russian Geographical Society expedition to Paramushir Island. Photo by K. Mikhailova.

O.V. Savinkin, T.I. Antokhina, and Yu.V. Deart, staff members of the A.N. Severtsov Institute of Ecology and Evolution of the Russian Academy of Sciences (IEE RAS), took part in the Russian Geographical Society's "Eastern Bastion – Kuril Ridge" expedition to Paramushir Island (Northern Kuril Islands) as part of a group of hydrobiologists. The expedition took place in July and August 2025, with the camp based in Krasheninnikov Bay, south of the island. A total of approximately 50 people worked on Paramushir, including volcanologists, botanists, ornithologists, entomologists, hydrobiologists, geographers, historians, volunteers, and others.

Fig. 2. The Kuril Ridge and the research site in Krasheninnikov Bay.

The hydrobiologists' primary goal was to study the biodiversity of the benthic fauna of Paramushir Island. Researchers from the Institute of Ecology and Evolution of the Russian Academy of Sciences (IEE RAS) conducted the research using lightweight diving equipment. Seven locations in Krasheninnikov Bay and the surrounding capes were surveyed (Fig. 2).

Fig. 3. Photographs of animals taken during processing of the material at the expedition camp. A – starfish Crossaster papposus (Linnaeus, 1767), B – symbiotic polychaete worm Arctonoe vittata (Grube, 1855), C – gastropod mollusk Boreotrophon cf. truncatus, D – shrimp Lebbeus grandimanus (Bražnikov, 1907). Photo: A, B, D – Antokhina T.I.; C – Deart Yu.V.

The dives revealed two contrasting biotopes: boulder bottoms virtually devoid of large animals, and rocky outcrops near the capes—oases inhabited by a multitude of sea urchins, starfish, polychaetes, anemones, soft corals, and mollusks (Figs. 3-4). Of particular interest is the astonishing species diversity of coelenterates—anemones, soft corals, and hydroids—which form unique underwater gardens that provide shelter for small invertebrates and fish. Another species-rich group is starfish, of which at least 15 species were encountered. The rock surface is covered with mussel brushes and clusters of sea urchins (Fig. 4).

Fig. 4. A – underwater landscape at Cape Amnat, depth 10-12 m, B – sea anemones Metridium farcimen (Brandt, 1835) and M. senile fimbriatum (Verrill, 1865), starfish and urchins at Cape Skalny, depth 18-20 m, C – sea anemone Cribrinopsis albopunctata Sanamyan et Sanamyan, 2006, D – starfish Leptasterias sp. Photo: Antokhina T.I.

During the dives, observations of benthic inhabitants (feeding behavior, symbiotic relationships, etc.) were conducted, and their environmental preferences were clarified.

Further laboratory work involves species identification of the collected specimens, study of morpho-anatomical characteristics using various methods, molecular genetic analysis of the samples, and investigation of embryonic and postembryonic development for individual sea anemone species.