ENVIRONMENTAL CONDITIONS IN THE COASTAL AREA OF BASIC SPAWNING BASINS OF PINK SALMON <i>ONCORHYNCHUS GORBUSCHA</i> AT WESTERN KAMCHATKA
The hydrological and hydrobiological survey carried out in early June 2018 at the western coast of Kamchatka at the beam of basic spawning rivers, on the polygon with less than 20 m depth has demonstrated, that abiotic conditions (temperature and oxygen content) were within optimal values for early marine rearing of pink salmon. Meant for polygon density of “forage” zooplankton of 313 mg/m3 characterizes trophic conditions at the potential areas of early marine rearing of pink salmon as favorable. But the distribution of plankton at the western coast of Kamchatka is nonregular. By means of statistical multivariate data analysis three zones of high productivity of plankton were revealed. These zones were associated with the coldest parts of water area. Throughout the most part of investigated polygon biomass of “forage” zooplankton is less than starting value 200 mg/m3. In the case of increase of commercial fishing importance of the area, the attention is focused on the necessity of hydrological monitoring and on finding methods of studying distribution and migrations of pink salmon juveniles, its trophic relations with other hydrobionts and evaluation of its abundance at early marine period.