Scale Pattern Analysis Discriminates Atlantic Salmon by River Reach Rearing Origin

Scale pattern analysis was used to discriminate among juvenile Atlantic salmon Salmo salar reared in different reaches of the Narraguagus River basin. Measurements of parr scales collected during 1990-1999 were used in a principal components analysis and to create linear discriminant functions for seven geographic strata and three river basin strata groups reflecting natural habitat breaks and Atlantic salmon management regimens. Discriminant functions were calculated with both pooled and annual data. Sufficient differentiation existed among rearing habitats of different reaches (or between geographically grouped reaches) in the Narraguagus River basin, particularly for tributary habitats, to allow discrimination to various degrees of possible use in management.