Canonical correlation analysis of relationships between management inputs and fish growth and yields in polyculture

Canonical correlation analysis was used to study the influence of management factors on growth and yields in an experimental polyculture system. The major conclusions are: (1) yield of each species was affected mainly by its own stocking density, followed by interactions with other species; (2) the best yields and growth rates of tilapia were obtained with stocking weights of over 13 g and; (3) common carp, Cyprinus carpio L., was affected negatively by silver carp, Hypoihalmichihys molitrix (Valenciennes), density and positively by nutrient inputs. Its best performance was obtained at silver carp density below 1000/ha. Analyses of data from commercial production units are required to confirm these conclusions