A survey of clusters of gray sea urchin (Strongylocentrotus intermedius) in the coastal zone of the islands of Iturup, Kunashir, Shikotan and the islands of the Lesser Kuril Ridge showed that the population of gray sea urchin is in a stable condition. In addition, the scientists noted signs of an increase in the total and commercial biomass of hydrobionts.
Animals were found on all types of soils, the most dense clusters were formed on rocky and boulder-stony soils. The frequency of occurrence of the gray sea urchin in the southern Kuril Islands averaged more than 65%.
The proportion of sea urchins with dark spots (scuffs) and without needles on the shell was insignificant, and external factors did not affect their vital activity. The real facts of the mass death of sea urchins were also not recorded.
VNIRO Press Service
