Abstract
Abstract Two hatchery stocks of juvenile spring chinook salmon Oncorhynchus tshawytscha originating from two southeast Alaska rivers were reared in freshwater to an average size of 8–10 g and placed in marine net-pens with an artificial freshwater lens system (AFLS) at four entry times from mid-September to early November 1987. Overwinter survival to May 1988 averaged 83.6% for Unuk River stock and 76.0% for Chickamin River stock and did not differ significantly in the AFLS among the four entry dates. Survival over 24 h differed significantly when entry was directly into 30‰ seawater. The 24-h plasma sodium levels in the juveniles challenged to either full-strength seawater or marine net-pens with an AFLS were not useful predictors of overwinter survival. Over winter, both stocks grew significantly better in the AFLS than in freshwater. The AFLS appears to be a cost-effective means of substantially increasing smolt production while minimizing freshwater use.
Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
