Variation in early growth and survival of pink salmon ( Oncorhynchus gorbuscha) families with respect to temperature and transfer to salt water

Abstract

Five pairs of paternal half-sib families of pink salmon ( Oncorhynchus gorbuscha) were transferred from fresh to 28‰ salt water 1, 7, and 28 days after button-up of the fry and reared for 51 days at 13°C. In another experiment, pink salmon from three populations were also reared in fresh and salt water at 9.5°C for 49 days after fry button-up. Juvenile growth and survival rates were greater when juveniles were reared for a period of time in fresh water after button-up. Juveniles transferred to salt water 1 day after button-up had the lowest growth and survival rates. Juveniles reared at 13°C grew up to five times faster than those reared at 9.5°C. There was evidence of genetic differences in juvenile growth and survival among half-sib families.