1. Comparative analysis of total mercury concentrations in anadromous and non-anadromous Arctic charr (Salvelinus alpinus) from eastern Canada
- Author
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van der Velden, S., Evans, M.S., Dempson, J.B., Muir, D.C.G., and Power, M.
- Subjects
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MERCURY compounds , *ARCTIC char , *ANADROMOUS fishes , *FRESHWATER fishes , *COMPARATIVE studies , *FISH populations - Abstract
Abstract: Previous research has documented that total mercury concentrations ([THg]) are lower in anadromous Arctic charr than in non-anadromous conspecifics, but the two life-history forms have rarely been studied together. Here, data from nine pairs of closely-located anadromous and non-anadromous Arctic charr populations were used to explore the impact of biological and life-history factors on individual [THg] across a range of latitudes (49–81° N) in eastern Canada. Unadjusted mean [THg] ranged from 20 to 114ng/g wet weight (ww) in anadromous populations, and was significantly higher in non-anadromous populations, ranging from 111 to 227ng/g ww. Within-population variations in [THg] were best explained by fish age, and were often positively related to fork-length and δ15N-inferred trophic level. Differences in [THg] were not related to differences in length-at-age (i.e., average somatic growth rate) among populations of either life-history type. Mercury concentrations were not related to site latitude in either the anadromous or non-anadromous fish. We conclude that the difference in Arctic charr [THg] with life-history type could not be explained by differences in fish age, fork-length, trophic position, or length-at-age, and discuss possible factors contributing to low mercury concentrations in anadromous, relative to freshwater, fish. [Copyright &y& Elsevier]
- Published
- 2013
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