Osmoregulatory capability in juvenile sockeye salmon (Oncorhynchus nerka)

The osmoregulatory capability of sockeye salmon (Oncorhynchus nerka) embryos and fry was tested at weekly intervals by exposing them for 5 days to seawater with a salinity of 29‰. Juveniles that survived the 5-day test were considered to be euryhaline. The fry acquired a salinity tolerance in March 1968 when they were 64 days old and less than 35–40 mm long. The juvenile salmon retained the ability to survive direct transfer to seawater during the 12-month period following March 1968.