AEI Aquaculture Environment Interactions Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsTheme Sections AEI 9:193-204 (2017) - DOI: https://doi.org/10.3354/aei00224 Effects of light source and intensity on sexual maturation, growth and swimming behaviour of Atlantic salmon in sea cages Tom Johnny Hansen*, Per Gunnar Fjelldal, Ole Folkedal, Tone Vågseth, Frode Oppedal Institute of Marine Research, 5984 Matredal, Norway *Corresponding author: tomh@imr.no ABSTRACT: We investigated how highly efficient LED light sources may be used in Atlantic salmon cage farming. Specifically, we tested the incidence of sexual maturation and growth patterns in autumn sea-transferred Atlantic salmon Salmo salar L. during their second sea winter given continuous artificial light (LL) (between 13 January and 18 June) of 5 different intensities using LED sources, compared to a single intensity provided by a metal halide (MH) source or a control treatment of natural light (NL). Growth effects were independent of light source, but increased with irradiance. We propose a model wherein sufficiently high irradiance from the artificial light source will give a long day signal throughout late winter and spring, an intermediate irradiation will give a long day signal until it is outcompeted by the seasonal increase in natural light, and an irradiance that is always below the threshold will not be perceived as different from natural light. Sexual maturation in males (6.1% under NL) was evenly arrested at all intensities, and swimming activity at night increased during winter in lit groups. We conclude that LED lamps may replace MH sources at similar intensity. Reducing the light irradiance of the superimposed light reduced the growth-stimulating effect, but all irradiances reduced the incidence of sexual maturation. KEY WORDS: Salmo salar · Photoperiod · Salmonid aquaculture · Cage environment Full text in pdf format PreviousNextCite this article as: Hansen TJ, Fjelldal PG, Folkedal O, Vågseth T, Oppedal F (2017) Effects of light source and intensity on sexual maturation, growth and swimming behaviour of Atlantic salmon in sea cages. Aquacult Environ Interact 9:193-204. https://doi.org/10.3354/aei00224 Export citation RSS - Facebook - Tweet - linkedIn Cited by Published in AEI Vol. 9. Online publication date: June 20, 2017 Print ISSN: 1869-215X; Online ISSN: 1869-7534 Copyright © 2017 Inter-Research.