명태의 수정란 부화 및 자어 생존에 미치는 염분의 영향

Abstract

The aim of this study was to investigate the influence of seawater salinity on hatching rate of fertilization eggs and larval survival of walleye pollock, Gadus chalcogrammus. The following water salinity was considered: 10, 15, 20, 25, 30 and 34 psu for the control (natural seawater). Survival of eggs maintained at 34 psu was greater than that of eggs maintained at different salinities for 12 days. The highest hatching rate was observed for larvae maintained at 34 psu, and higher than other salinity treatments. Time to first hatch of eggs maintained at 10, 15 and 20 psu was longer than at 25, 30 and 34 psu. However, time to 50% and 100% hatch of eggs maintained at 10 psu was shorter than those of eggs maintained at 25, 30 and 34 psu. Survival of larvae at 34 psu was greater than larvae at all other salinity treatments. Therefore, the best results of hatching rate of fertilization eggs and larval survival were obtained when eggs and larvae were reared in the salinity of 34 psu.