Estimated Escapement of Atlantic Salmon ( Salmo salar ) for Maximum Smolt Production in Rivers of Different Productivity

• Published in: Journal of the Fisheries Research Board of Canada
• Main Author: Symons, Philip E. K.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Canadian Science Publishing 1979
• Subjects: General Medicine; Atlantic salmon; Salmo salar
• Online Access: http://dx.doi.org/10.1139/f79-022; http://www.nrcresearchpress.com/doi/pdf/10.1139/f79-022

Smolt production at different egg deposition densities is estimated from data on survival rates and space requirements of juvenile Atlantic salmon (Salmo salar) reported in the literature. Average maximum production of smolts is estimated to be approximately 5/100 m 2 for 2+ smolts, 2/100 m 2 for 3+ smolts, and 1/100 m 2 for 4+ smolts. Minimum egg depositions recommended for production of these numbers of smolts are 220/100 m 2 , 165–220/100 m 2 , and 80/100 m 2 for each age of smolts, respectively. The escapement of adults required to produce these depositions must be estimated from observed average weights of returning females and a reported fecundity of Atlantic salmon between 1650 and 1760 eggs/kg of female. With the exception of Ungava rivers, average smolt age in any particular river can be estimated from the number of days per year on which water temperature reaches or exceeds 7 °C. Key words: fishery resources, fishery management, production (biological), escapement, survival, game fish, freshwater fish, rivers