Night stocking facilitates nocturnal migration of hatchery‐reared Atlantic salmon, Salmo salar, smolts

Abstract Hatchery‐reared salmon, Salmo salar L., smolts are generally stocked during daylight hours, but the natural migration of smolts tends to occur at night. Recapture rates and timing of migration were compared between Atlantic salmon smolts stocked during the day and during the evening. Timing...

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Bibliographic Details
Published in:Fisheries Management and Ecology
Main Authors: ROBERTS, L. J., TAYLOR, J., GOUGH, P. J., FORMAN, D. W., De LEANIZ, C. GARCIA
Format: Article in Journal/Newspaper
Language:English
Published: Wiley 2009
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Online Access:http://dx.doi.org/10.1111/j.1365-2400.2008.00611.x
https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1111%2Fj.1365-2400.2008.00611.x
https://onlinelibrary.wiley.com/doi/pdf/10.1111/j.1365-2400.2008.00611.x
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Summary:Abstract Hatchery‐reared salmon, Salmo salar L., smolts are generally stocked during daylight hours, but the natural migration of smolts tends to occur at night. Recapture rates and timing of migration were compared between Atlantic salmon smolts stocked during the day and during the evening. Timing of release had no significant effect on the number of smolts recaptured, but had a strong effect on nocturnal behaviour. When stocked in the evening (but not during the day) hatchery‐reared smolts moved almost exclusively during the night. This study suggests that timing the release to coincide with the natural time of smolt migration may provide valuable acclimatisation and facilitate nocturnal smolt passage.