E Leclercq, JF Taylor, M Sprague and H.Migaud – Institute of Aquacultural Engineering.
The aim of this study was to compare the efficiency of new candidate lighting-technologies (50W ‘blue’ light-emitting-diode (B, λmax = 465 nm); 232 W ‘green’ hot cathode, (G, λmax = 546 nm); 400 W ‘red’ tungsten-halogen, (R, λmax = 667 to 740 nm)) against a standard 400 W ‘white’ metal-halide used as control technology (C, broad spectrum) at suppressing sexual maturation of 1+ Atlantic salmon (Salmo salar) in sea-cages. A total of seven experimental set-ups were tested on a commercial-scale in three trials using a standardised photoperiod regime in the form of continuous artificial-light (LL) applied from winter to summer solstice during the second year at sea. The experimental stocks were raised under an ambient thermal regime that was similar across all trials.