Migratory behaviour of wild and farmed Atlantic salmon (<i>Salmo salar</i>) during spawning

Økland, Finn; Heggberget, Tor G.; Jönsson, Bror

doi:10.1111/j.1095-8649.1995.tb05942.x

Cited by 61 publications

(39 citation statements)

References 16 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Studies that have examined the interaction of wild and escaped farmed salmon occasionally report that farmed fish enter the rivers later (Gausen and Moen, 1991), tend to spawn more in the lower reaches of a river, and later in the year (Webb et al, 1991) than wild salmon although this is not consistent among all studies (Okland et al, 1995). In our experiment, the first group was released to coincide with the timing of the natural salmon return to Conne River, but the cage-reared wild fish generally delayed their return to the river for several weeks.…”

Section: Discussionmentioning

confidence: 98%

Evaluation of an alternative strategy to enhance salmon populations: Cage rearing wild smolts from Conne River, Newfoundland

Dempson

1999

ICES Journal of Marine Science

View full text Add to dashboard Cite

Section: Discussionmentioning

confidence: 98%

Evaluation of an alternative strategy to enhance salmon populations: Cage rearing wild smolts from Conne River, Newfoundland

Dempson

1999

ICES Journal of Marine Science

View full text Add to dashboard Cite

“…No erratic movement pattern was found in farmed compared to wild salmon during the upstream migration phase (Heggberget et al 1996), but the farmed fish showed more and longer up-and downstream movements during the spawning period (Økland et al 1995;. Despite a tendency for farmed salmon being distributed higher up in the river during spawning, wild and farmed salmon were not geographically separated, and farmed fish occurred in parts of the river with important wild salmon spawning areas (Heggberget et al 1996;Butler et al 2005).…”

Section: Previous Experiencementioning

confidence: 92%

Factors affecting the within-river spawning migration of Atlantic salmon, with emphasis on human impacts

Thorstad

Økland

Aarestrup³

et al. 2007

Rev Fish Biol Fisheries

205

236

View full text Add to dashboard Cite

We review factors affecting the withinriver spawning migration of Atlantic salmon. With populations declining across the entire distribution range, it is important that spawners survive in the last phase of the spawning migration. Knowledge on the factors affecting migration is essential for the protection of populations, and to increase the success of reintroduction programmes. A number of studies have documented that the upstream migration may be delayed for many weeks at man-made obstacles such as power station outlets, residual flow stretches, dams, weirs and fishways. The fish may also be delayed at natural migration barriers. Often, the magnitude of delay is not predictable; fish may be considerably delayed at barriers that appear to humans to be easily passable, or they may quickly pass barriers that appear difficult. Stressful events like catch-and-release angling may affect upstream migration. Impacts of human activities may also cause altered migration patterns, affect the withinriver distribution of the spawning population, and severe barriers may result in displacement of the spawning population to other rivers. Factors documented to affect within-river migration include previous experience, water discharge, water temperature, water velocity, required jump heights, fish size, fish acclimatisation, light, water quality/pollution, time of the season, and catch and handling stress. How each of these factors affects the upstream migration is to a varying extent understood; however, the effects may differ among different river sections and sites. There are likely a number of additional important factors, and the relationship between different factors is complex. The understanding of general mechanisms stimulating fish within-river migration are still lacking, and it cannot be reliably predicted under which conditions a fish will pass a given migration barrier or which conditions are needed to stimulate migration at different sites. The strong focus on the effects of water discharge in past work may have hampered consideration of other factors. Exploration of the influence of these other factors in future studies could improve our understanding of what controls the upstream migration.

show abstract

“…Cultured Atlantic salmon enter rivers to spawn later in the season, move about more, and stay in the river for a shorter time than wild fish (Jonsson et al, 1990;Økland et al, 1995). That cultured fish are not homing to any particular spawning area, probably influences upstream migration.…”

Section: Spawningmentioning

confidence: 99%

“…;Riley et al, 2005 River movement B Jonsson et al, 1990;Økland et al, 1995 . River stay B. Jonsson et al, 1990 Straying to foreign riversHansen et al, 1993; B. Jonsson et al, 2003 Predator recognition Brown andSmith, 1998;Mirza and Chivers, 2000;Berejikian et al, 2003b; Vilhunen et al, 2005 Refuge use Griffiths andOrpwood et al, 2004Rungruangsak-Torrissen et al, 1998; N. Jonsson et al, 2005 Protein synthesis Rungruangsak-Torrissen et al, 1998, 1999 Maintenance ration Rungruangsak-Torrissen et al, 1998, 1999 Youngson and Webb, 1992; McCormick et al, 2003 Adiposy Rowe et al, 1991; Silverstein et al, 1999 Maturity age Patterson et al, 2004 Swimming performance McDonald et al, 1998; Claireaux et al, 2005 Fin healing Jørgensen and Jobling, 1993…”

mentioning

confidence: 99%

Cultured Atlantic salmon in nature: a review of their ecology and interaction with wild fish

Jönsson

2006

ICES Journal of Marine Science

238

190

View full text Add to dashboard Cite

N. 2006. Cultured Atlantic salmon in nature: a review of their ecology and interaction with wild fish. e ICES Journal of Marine Science, 63: 1162e1181.When cultured Atlantic salmon are released into nature, they compete with wild fish for food, space, and breeding partners. As a result of morphological, physiological, ecological, and behavioural changes that occur in hatcheries, their comp etitive ability often differs from that of wild fish. These changes are partly phenotypic and partly genetic. Cultured juveniles' faster growth rate influences age and size at smolting and maturity, reproductive output, and longevity. Fast-growing parr tend to smolt younger, produce more but smaller eggs, attain maturity earlier, and die younger. Juvenile learning influences a number of behavioural traits, and differences in early experience appear to affect feeding and spawning success, migratory behaviour, and homing ability. Genetic change in hatcheries is chiefly the result of natural selection, with differential mortality among genotypes and broodstock selection based on production traits such as high adult body mass and fast growth rate. Experimental evidence has revealed that cultured parr's greater aggression often allows them to dominate wild parr, although smaller cultured parr can be subordinated if they co-occur in fast-flowing water and if wild smolts have established prior residence. During spawning, the fitness of wild salmon is superior to that of cultured conspecifics. Cultured males are inferior to wild males in intra-sexual competition, courting, and spawning; cultured females have greater egg retention, construct fewer nests, and are less efficient at covering their eggs in the substratum than their wild counterparts. In rivers, the early survival of cultured offspring is lower than that of their wild counterparts. The lifetime reproductive success of farmed fish has been estimated at 17% that of similar-sized wild salmon. As a result of ecological interaction and through density-dependent mechanisms, cultured fish may displace wild conspecifics to some extent, increase their mortality, and decrease their growth rate, adult size, reproductive output, biomass, and production.

show abstract

Migratory behaviour of wild and farmed Atlantic salmon (Salmo salar) during spawning

Cited by 61 publications

References 16 publications

Evaluation of an alternative strategy to enhance salmon populations: Cage rearing wild smolts from Conne River, Newfoundland

Evaluation of an alternative strategy to enhance salmon populations: Cage rearing wild smolts from Conne River, Newfoundland

Factors affecting the within-river spawning migration of Atlantic salmon, with emphasis on human impacts

Cultured Atlantic salmon in nature: a review of their ecology and interaction with wild fish

Contact Info

Product

Resources

About