Freshwater C, Trudel M, Beacham T D, Neville C-E, Tucker S, Juanes F
Department of Biology, University of Victoria, Victoria, BC, V8W 3N5, Canada.
Fisheries and Oceans Canada, Pacific Biological Station, Nanaimo, BC, V9T 6N7, Canada.
J Fish Biol. 2015 Jul;87(1):169-78. doi: 10.1111/jfb.12688. Epub 2015 May 11.
Juvenile sockeye salmon Oncorhynchus nerka that were reared and smolted in laboratory conditions were found to produce otolith daily increments, as well as a consistently visible marine-entry check formed during their transition to salt water. Field-collected O. nerka post-smolts of an equivalent age also displayed visible checks; however, microchemistry estimates of marine-entry date using Sr:Ca ratios differed from visual estimates by c. 9 days suggesting that microstructural and microchemical processes occur on different time scales.
