Diel activity patterns of juvenile Atlantic salmon in rivers with summer water temperature near the temperature‐dependent suppression of diurnal activity
Abstract:Direct day and night underwater observations of juvenile Atlantic salmon Salmo salar during summer and autumn showed a duality in response to temperature between 7 and 11° C for young‐of‐the‐year (YOY) Atlantic salmon. They were predominantly diurnal in early summer and nocturnal in late summer although water temperatures were similar. Post‐YOY Atlantic salmon did not show a strong response to temperature as they were mostly nocturnal during the study period. It is suggested that the difference in activity patterns between YOY and post‐YOY Atlantic salmon can be explained by size‐dependent trade‐off between growth and predation risk.
Document Type: Regular Paper
Affiliations: 1: INRS-Eau, Terre et Environnement, 880 ch. Sainte-Foy, bur. 840, C.P. 7500, Québec, QC, G1V 4C7, Canada and 2: Département de biologie, Université Laval, Cité universitaire, Québec, QC, G1K 7P4, Canada
Publication date: 2004-11-01