Interaction entre le débit et les populations de tacons ( Salmo salar ) de la rivière Matamec, Québec

• Published in: Canadian Journal of Fisheries and Aquatic Sciences
• Main Authors: Frenette, M., Caron, M., Julien, P., Gibson, R. J.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Canadian Science Publishing 1984
• Subjects: Aquatic Science; Ecology, Evolution, Behavior and Systematics; Salmo salar
• Online Access: http://dx.doi.org/10.1139/f84-109; http://www.nrcresearchpress.com/doi/pdf/10.1139/f84-109

Given the hypothesis that in a river, the population of young salmon (Salmo salar), called parr after the first year, is directly related to the discharge-variable physical characteristics of the habitats, a multiple linear regression analysis was carried out between the parr population estimates in the Matamec River (north shore of the Gulf of St. Lawrence) and the minimum, average, and maximum discharges for monthly and seasonal periods. The most significative variables were obtained for the minimum discharge before flooding (around April), the average August discharge of the year before last (2 yr before), and the average July discharge of the previous year. These discharges corresponded to critical biological periods for the young salmon present in the river and were used to develop a prediction model that was loaded with data covering the period 1971–77. The predictions obtained were 95% significant when the three independant parameters were used jointly and reached more than 66% when only one parameter was taken into account. Overall, it is shown that the discharge is an important limiting factor directly influencing salmon survival in streams.