Competitive Asymmetries in Territorial Juvenile Atlantic Salmon, Salmo salar

Stress Responsiveness Affects Dominant–Subordinate Relationships in Rainbow Trout

“…Both relative size (where differences between individuals are substantial; Cutts, Metcalfe and Taylor, 1999) and prior residency (Huntingford and de Leaniz, 1997;Johnsson, Nobbelin and Bohlin, 1999) are important factors in determining the outcome of competitive interactions in salmonid fish, therefore paired fish were size-matched and contests were conducted in an arena comprising the combined "home" compartments of both fish. Fish were not handled following initial transfer to the test tanks and the only potentially stressful stimulus that was imposed prior to the contest was removal of the partition, an event experienced simultaneously by both fish.…”

Multigenerational hybridisation and its consequences for maternal effects in Atlantic salmon

“…Large eggs result in large offspring but are under evolutionary constraints because of the trade-off between egg size and egg number (Sargent et al, 1987). Time of emergence may also affect fitness with earlier emerging fry advantageously finding territories first (Cutts et al, 1999;Mogensen and Hutchings, 2012) but being at a disadvantage under predation (Brännäs, 1995).…”

“…The phase following fry emergence has been identified as a 'critical period' because of high mortalities caused by predation and starvation (Elliott, 1990;Einum and Fleming, 2000). It is generally accepted that larger fry are fitter through advantages in feeding territory acquisition (Elliott, 1990;Cutts et al, 1999), with larger sizes of only a few per cent resulting in dominance advantages (Berejikian et al, 1996), and predator avoidance (Mogensen and Hutchings, 2012). Large eggs result in large offspring but are under evolutionary constraints because of the trade-off between egg size and egg number (Sargent et al, 1987).…”

Prior residence, territory quality and life-history strategies in juvenile Atlantic salmon (Salmo salar L.)

“…All fish were of similar size, showing that prior residence alone, and not the size advantage it may subsequently confer, has a strong influence on which individuals obtain territories. Therefore prior residence, and with it information about the territory's resource value, is reflected in the increased competitive ability of the fish (Cutts et al, 1999). Across all groups, aggression correlated significantly with size.…”

“…Early emerging juveniles are competitively superior to their later emerging conspecifics, by being first to acquire the available territorial space, and are also larger by the time other juveniles emerge (Mason & Chapman, 1965;Chandler & Bjornn, 1988;Metcalfe & Thorpe, 1992). Such differences in competitive ability due to relative time of emergence obscure intrinsic differences in competitive ability (Cutts et al, 1999;Johnsson et al, 1999).…”