GROWTH AND SURVIVAL OF JUVENILE RAINBOW TROUT PARASALMO MYKISS WAL. IN THE CONDITIONS OF THE KONDOPOGA BAY OF ONEGA LAKE (KARELIA)

Dzyubuk Irina Mikhailovna

The results on the growth and survival of juvenile rainbow trout Parasalmo mykiss Wal., obtained from spawners grown in the Kaluga region (Russia) and Finland, in the Kondopoga Bay of Onega Lake have been presented. The growing conditions for juveniles were favorable, most of the values of hydrochemical parameters were close to optimal, except for the values of biological oxygen consumption and iron content in water. The water temperature in July reached 18С, which was close to the critical limit. The absolute weight gain of the Finnish fry was 32 g and that of the Kaluga fry – 77 g. The survival rate of the fry was high (98.9–99.9%). Correlation analysis confirmed a high degree of correlation between the mortality of Finnish fry and water temperature. The results of the studies showed that, when grown in the Kondopoga Bay of Onega Lake, the Kaluga juvenile rainbow trout was distinguished by a lower intensity of mass accumulation, but a high survival rate with an increase in water temperature to values close to critical, in contrast to the Finnish juveniles.

Keywords:cage fish farming, Onega Lake, rainbow trout, juveniles, fry, fingerlings, rearing, survival rate