Effects of Tagging and of Fin-clipping on the Survival and Growth of Atlantic Salmon Between Smolt and Adult Stages

• Published in: Journal of the Fisheries Research Board of Canada
• Main Authors: Saunders, Richard L., Allen, K. Radway
• Format: Article in Journal/Newspaper
• Language: English
• Published: Canadian Science Publishing 1967
• Subjects: Atlantic salmon
• Online Access: http://dx.doi.org/10.1139/f67-208; http://www.nrcresearchpress.com/doi/pdf/10.1139/f67-208

Rates of recapture of Atlantic salmon marked as naturally produced smolts in the Northwest Miramichi River, New Brunswick, were 2.9 for tagged and 3.9% for fin-clipped grilse and 0.7 for tagged and 1.8% for fin-clipped larger salmon. There are indications that survival to the adult stage is much higher for unmarked smolts than for tagged or fin-clipped fish. Length measurements of 117 tagged, 607 fin-clipped, and 301 unmarked grilse taken above tidehead in the Northwest Miramichi showed that those entering freshwater early in the season were smaller that those entering later. Tagged grilse were shorter than fin-clipped grilse which returned at the same time, and the fin-clipped grilse were shorter than unmarked ones. Rates of increase in size among tagged, fin-clipped, and unmarked grilse during the season of return to freshwater (June through October) did not differ significantly.