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Providing evidence to improve practice

Action: Alter cage size Sustainable Aquaculture

Key messages

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  • A replicated study in Australia recorded lower levels of amoebic gill disease in salmon kept within larger compared to smaller cages.

Supporting evidence from individual studies


In 2000, a replicated study in Tasmania, Australia (Douglas- Helders et al., 2004) found higher levels of amoebic gill disease salmon, Salmo salar, stocked in 60m diameter round cages compared to those in 80m diameter cages. Levels of amoebic gill disease were 47% and 22%, respectively. Two cages with a diameter of 60m and three of 80m diameter were used for the study. Average biomass per pen was 2337 kg for the 60m cages and 2806 kg for the 80m cages. Monthly samples were taken from August to November. Signs of clinical disease were assessed using the routine Tasmanian salmon farmers gill assessment method.


Referenced papers

Please cite as:

Jones, A.C., Mead, A., Austen, M.C.V.  & Kaiser, M.J. (2013) Aquaculture: Evidence for the effects of interventions to enhance the sustainability of aquaculture using Atlantic salmon (Salmo salar) as a case study. Bangor University