Scale microchemistry as a tool to investigate the origin of wild and farmed Salmo salar

Adey, E.A., Black, K.D., Sawyer, T., Shimmield, T.M. and Trueman, C.N. (2009) Scale microchemistry as a tool to investigate the origin of wild and farmed Salmo salar. Marine Ecology Progress Series, 390, 225-235. (doi:10.3354/meps08161).

Abstract

Atlantic salmon Salmo salar are extensively farmed throughout their natural range, and
unintentional interactions between farmed fish and wild populations have been implicated in the
decline of wild salmon. The trace element composition of salmon scales distinguishes wild from
farmed fish, and potentially provides a rapid and cheap method to assess the extent of escaped
farmed fish within a wild population. Scale samples from wild and farmed fish from sites throughout
Scotland were analysed for a large number of trace elements using inductively coupled plasma mass
spectrometry (ICP-MS). Discriminant function analysis of the resulting data classified wild and
farmed fish with 98% accuracy. Mn is identified as the element contributing most to the dissimilarity
between wild and farmed fish, with scales from farmed fish yielding significantly higher concentrations
of Mn. Scale chemistry also differed between farms. 87% of samples taken from six farm sites
around the west coast of Scotland were correctly classified to their farm of origin. Scale chemistry
provides a powerful tool to determine the origin of S. salar, despite the potential for post-depositional
change in elemental concentrations of scale bioapatite.

This record has no associated files available for download.

Contributors

Author: C.N. Trueman

Download statistics