Trying to choose the less bad route: Individual migratory behaviour of Atlantic salmon smolts (Salmo salar L.) approaching a bifurcation between a hydropower station and a navigation canal

Previous studies have shown kin recognition abilities in salmonid fish. Some authors have suggested that the attraction of juvenile fish to siblings may indicate preference for shoaling with kin. The aim of the present study is to test the prerequisite for the hypothesis that siblings swim spatially closer than unrelated fish during their seaward migration as smolts. Atlantic salmon (Salmo salar) eggs from three families were each reared in two tanks to create familiar and unfamiliar sibling smolts. Before the experiment started they were tagged individually withpassive integrated transponders (PITs). Twelve individuals from each of six groups were mixed and released together at several occasions in the upper end of the 400-m-long experimental stream. An automatic PIT-monitoring system placed in the outlet recorded the time for passage of each individual leaving the stream. Eighty-five percent of the juveniles monitored by the PIT antenna showed downstream migration at night hours and they migrated significantly more often closer in time to both known and unknown siblings than to unrelated fish. The results suggest that there is a genetic component in the migratory behaviour of Atlantic salmon smolts and support the hypothesis that smolts migrate in kin-structured groups.

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The pre-spawning migratory behaviour of Atlantic salmon Salmo salar in a large lacustrine catchment

Journal of Fish Biology ◽

10.1111/jfb.13068 ◽

2016 ◽

Vol 89 (3) ◽

pp. 1651-1665 ◽

Cited By ~ 4

Author(s):

R.J. Kennedy ◽

M. Allen

Keyword(s):

Atlantic Salmon ◽

Salmo Salar ◽

Migratory Behaviour ◽

Atlantic Salmon Salmo Salar

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The migratory behaviour of wild Atlantic salmon (Salmo salar) smolts in the estuary of the River Conwy, North Wales

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f95-784 ◽

1995 ◽

Vol 52 (9) ◽

pp. 1923-1935 ◽

Cited By ~ 93

Author(s):

A. Moore ◽

E. C. E. Potter ◽

N. J. Milner ◽

S. Bamber

Keyword(s):

Atlantic Salmon ◽

Water Column ◽

Fresh Water ◽

Seasonal Change ◽

Salmo Salar ◽

Coastal Waters ◽

Salt Water ◽

Migratory Behaviour ◽

Atlantic Salmon Salmo Salar ◽

North Wales

Thirty-two wild Atlantic salmon (Salmo salar) smolts, tagged with miniature acoustic transmitters, were tracked in the River Conwy, North Wales, to describe the freshwater and estuarine patterns of migration. Migration in fresh water was predominantly nocturnal, although there was a seasonal change in this pattern with later run fish moving during both the day and night. Smolts tagged earlier in the study spent significantly longer in the river (mean 456 ± 43 h) before migrating into coastal waters than fish tagged later in the study (mean 201 ± 30 h). The movement of smolts through the estuary was indicative of a nocturnal selective ebb tide transport pattern of migration. All of the smolts migrated seawards on an ebb tide close to the surface and within the fastest moving section of the water column. The nocturnal pattern of migration would appear to be the result of an endogenous rhythm of swimming activity that results in the smolts moving up into the water column after dusk and migrating seawards. Smolt migration in the lower portion of the estuary was indicative of active directed swimming and there was no apparent period of acclimation required when moving from fresh to salt water.

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Initial mortality of radio-tagged Atlantic salmon (Salmo salar L.) smolts following release downstream of a hydropower station

Aquatic Telemetry ◽

10.1007/978-94-017-0771-8_5 ◽

2002 ◽

pp. 31-37 ◽

Cited By ~ 3

Author(s):

A. Koed ◽

N. Jepsen ◽

K. Aarestrup ◽

C. Nielsen

Keyword(s):

Atlantic Salmon ◽

Salmo Salar ◽

Hydropower Station ◽

Atlantic Salmon Salmo Salar

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