Temps d'ajustement de la flottabilité des saumons atlantiques ( Salmo salar ) d'élevage et flottabilité comparée de saumons atlantiques d'élevage et sauvages

• Published in: Canadian Journal of Fisheries and Aquatic Sciences
• Main Authors: Legault, Michel, Lalancette, Louis-Marie
• Format: Article in Journal/Newspaper
• Language: English
• Published: Canadian Science Publishing 1985
• Subjects: Aquatic Science; Ecology, Evolution, Behavior and Systematics; Atlantic salmon; Salmo salar
• Online Access: http://dx.doi.org/10.1139/f85-081; http://www.nrcresearchpress.com/doi/pdf/10.1139/f85-081

We determined the time of adjustment of buoyancy of juvenile hatchery-reared Atlantic salmon (Salmo salar) and investigated whether if their higher position off the substratum, compared with wild fish, might better result from a higher buoyancy. In flowing water, hatchery-reared Atlantic salmon adjust their buoyancy within 24 h. No difference in buoyancy exists between juvenile hatchery-reared and wild Atlantic salmon in still water. However, juvenile hatchery-reared Atlantic salmon are more buoyant in flowing water than wild Atlantic salmon. Even after 3 mo in a stream, the buoyancy of juvenile hatchery-reared Atlantic salmon did not change. Acquired hatchery behaviour appears to be responsible for their difference in buoyancy.