Genetic influence of parr versus anadromous sires on the life histories of Atlantic salmon ( Salmo salar )

• Published in: Canadian Journal of Fisheries and Aquatic Sciences
• Main Authors: Duston, J, Astatkie, T, MacIsaac, P F
• Format: Article in Journal/Newspaper
• Language: English
• Published: Canadian Science Publishing 2005
• Subjects: Aquatic Science; Ecology, Evolution, Behavior and Systematics; Atlantic salmon; Salmo salar
• Online Access: http://dx.doi.org/10.1139/f05-120; http://www.nrcresearchpress.com/doi/pdf/10.1139/f05-120

The potential for sire size to influence life history patterns from fry to sea age at maturity was established by rearing individually identified half-sibs of a single dam and either small (parr) or large (anadromous) sires in a common tank environment. Male sexual maturity was higher among progeny of small versus large sires at both parr (age 0+, 50% versus 32%, p = 0.065) and grilse stages (age 2+, 23% versus 10%, p = 0.034). In contrast, rates of female grilse (6.8%) and smolt age 1+ (>95%) were independent of sire size. Logistic regression indicated that grilse of small sires had an asymptote body weight (BW) 30% lower than grilse of large sires (1.0 versus 1.4 kg). In comparison, repeated measures analysis of BW, fork length (FL), and condition factor (CF) indicated that growth changes associated with grilsing were independent of sire size and sex. The highest-order interaction for which sire size was significant was day × sire × sex (p < 0.034). Independent of sire size, sexual maturation at both age 0+ and age 2+ was associated with a high CF, whereas smolting at age 1+ was associated with a high BW and FL but low CF.