LE3 .A278 2009

2009

Dadswell, Michael

Acadia University

Master of Science

Masters

Biology

Biology

In this study the utility of otolith elemental fingerprints for discriminating river specific stocks of Atlantic salmon was examined. Otoliths were removed from Atlantic salmon smolts collected in May and June 2001 from three rivers in the Canadian Maritimes: the Northwest Miramichi River and Southwest Miramichi River, New Brunswick, and the Margaree River, Nova Scotia. They were analysed for 27 elements using inductively coupled plasma mass spectrometry ( ICPMS) and inductively coupled plasma emission spectrometry ( ICPES). Calcium and 11 minor and trace elements could be precisely measured in whole otoliths at concentrations significantly above the detection limits. Univariate analyses indicated that six of these elements ( Ba, Pb, Li, Mn, Rb, and Tl) were significantly different among rivers, although only Mn differed significantly among all three rivers. The same six elements contributed to a significant difference among rivers when analysed as a multivariate fingerprint. Linear discriminate function analysis based on concentrations of four elements ( Li, Mn, Rb, and Tl) classified Atlantic salmon to their river of origin with an average accuracy of 73 % and correctly identified 93 % of the Margaree River, 77 % of the Southwest Miramichi River, and 46 % of the Northwest Miramichi River smolts. Discriminant analysis generated from a regional grouping of data ( NW Miramichi and SW Miramichi versus Margaree) and based on concentrations of four elements ( Ba, Li, Mn, and Rb) resulted in a mean classification accuracy of 93 %. Results of this study indicate that otolith elemental fingerprints could be used to discriminate among individual river stocks of Atlantic salmon. However, they may be more effective as a natural tag of biogeoclimatic region of origin.

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https://scholar.acadiau.ca/islandora/object/theses:127