Monitoring of water quality parameters affecting the commercial characteristics of the sea urchin Strongylocentrotus intermedius

The hydrochemical parameters of natural seawater quality in the coastal waters of the Sea of Japan during the spring-summer period of 2024 were investigated. An assessment of the influence of the studied parameters on the commercial characteristics of the gray sea urchin Strongylocentrotus intermedius was carried out. In Dunai Bay, an exceedance of the maximum allowable concentration (MAC) for chloride ions was recorded, indicating probable pollution by wastewater. No exceedances of heavy metals in bottom sediments were detected. Individuals in Dunai Bay were noted to have a greater body weight and a significantly higher gonadosomatic index, indicating a significant influence of environmental conditions on reproductive function. The obtained data are necessary for the science-based management of the fishery and reproduction of this aquatic organism.