Quantifying Elements in Arctic Grayling and Bull Trout in the South Nahanni River Watershed, Northwest Territories, Using Nonlethal Tissue Samples

AbstractMonitoring of contaminants in fish generally involves lethal sampling, but public scrutiny and increased pressure on fisheries have driven the need to develop nonlethal sampling methods. We examined the ability of adipose, anal, and caudal fin tissues to serve as nonlethal surrogates for lethal muscle tissue samples in the analysis of metals (elements). First, we evaluated the use of biopsies by examining relationships between concentrations of 39 elements in low-volume dorsal muscle biopsies and high-volume muscle samples from Arctic Grayling Thymallus arcticus and Bull Trout Salvelinus confluentus collected in the South Nahanni River watershed, Northwest Territories, Canada. Low-volume dorsal biopsy samples in this study served to most closely model the concentrations of elements found in high-volume dorsal samples; caudal and anal fins were more representative of high-volume dorsal samples than were adipose fins. Regressions between high- and low-volume dorsal muscle samples were significant fo...