Particulate waste outflow from fish-farming cages. How much is uneaten feed?
Particulate wastes drive benthic organic enrichment from cage fish farming. Differentiation between faeces and uneaten feed estimates at cage level are of great value to both economize the feeding process and reduce waste. This study estimates the particulate waste outflowing cages at different depths and orientations, and the wasted feed component by combining in situ measurements and modelling. Particulate matter flux (PMF) was greater vertically through the cage bottoms (60.89%), but lateral outflow was also substantial (39.11%). PMF occurs all around the cages, and the influence of the mainstream current was low. Wasted feed was greatly variable, reaching high values (about 50% of supplied feed. The self-application of feed wastage monitoring and estimates by fish farmers is recommended to improve sustainability.
Instituto Murciano de Investigación y Desarrollo Agrario y Alimentario (IMIDA), Estación de Acuicultura Marina, Puerto de San Pedro del Pinatar, 30740 Murcia, Spain.
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M
Ballester-Moltó
Departamento de Ciencias del Mar y Biología Aplicada, Universidad de Alicante, PO Box 99, 03080 Alicante, Spain.
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P
Sanchez-Jerez
Instituto Murciano de Investigación y Desarrollo Agrario y Alimentario (IMIDA), Estación de Acuicultura Marina, Puerto de San Pedro del Pinatar, 30740 Murcia, Spain.
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J
Cerezo-Valverde
Instituto Murciano de Investigación y Desarrollo Agrario y Alimentario (IMIDA), Estación de Acuicultura Marina, Puerto de San Pedro del Pinatar, 30740 Murcia, Spain. Electronic address: felipe.aguado@carm.es.
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F
Aguado-Giménez
D000818:Animals; D017756:Aquaculture; D005399:Fishes; D010316:Particle Size; D012037:Refuse Disposal
Current direction; Fish cages; Particulate waste flux; Passive waste sampler; Wasted feed