Lakeward Migrations by Juvenile Atlantic Salmon, Salmo salar

Atlantic salmon parr, Salmo salar, undertook lakeward migrations from outlet streams in the Wings Brook system, eastern Newfoundland. Lakeward movement occurred from May through November, intensifying over a 6- to 8-wk period during spring. Parr remained in the lakes where they either matured (usual...

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Bibliographic Details
Published in:Canadian Journal of Fisheries and Aquatic Sciences
Main Author: Hutchings, Jeffrey A.
Format: Article in Journal/Newspaper
Language:English
Published: Canadian Science Publishing 1986
Subjects:
Online Access:http://dx.doi.org/10.1139/f86-090
http://www.nrcresearchpress.com/doi/pdf/10.1139/f86-090
Description
Summary:Atlantic salmon parr, Salmo salar, undertook lakeward migrations from outlet streams in the Wings Brook system, eastern Newfoundland. Lakeward movement occurred from May through November, intensifying over a 6- to 8-wk period during spring. Parr remained in the lakes where they either matured (usually males) or smoltified (predominantly females) before returning to the streams. Mature parr emigrated from the lakes during autumn whereas smolts entered the streams during spring. Lakes provided conditions for increased parr growth and survival to the smolt stage relative to the riverine environment, and appeared to represent important overwintering habitat. Smolt production occurred almost entirely within the lakes. Parr movement into lakes could not be explained by physical environmental factors. Lakeward migrations appear to have an adaptive basis and can be explained as an evolutionarily stable reproductive tactic.