Relationship between Mercury Accumulation in Young-of-the-Year Yellow Perch and Water-Level Fluctuations

Abstract

A three-year (2001-2003) monitoring effort of 14 northeastern Minnesota lakes was conducted to document relationships between water-level fluctuations and mercury bioaccumulation in young-of-the-year (YOY) yellow perch (Perca flavescens) collected in the fall of each year at fixed locations. Six of those lakes are located within or adjacent to Voyageurs National Park and are influenced by dams on the outlets of Rainy and Namakan lakes. One site on Sand Point Lake coincides with a location that has nine years of previous monitoring suitable for addressing the same issue over a longer time frame. Mean mercury concentrations in YOY yellow perch at each sampling location varied significantly from year to year. For the 12-year monitoring site on Sand Point Lake, values ranged from 38 ng gww(-1) in 1998 to 200 ng gww(-1) in 2001. For the 14-lake study, annual mean concentrations ranged by nearly a factor of 2, on average, for each lake over the three years of record. One likely factor responsible for these wide variations is that annual water-level fluctuations are strongly correlated with mercury levels in YOY perch for both data sets.

Influence of Fluctuating Water Levels on Mercury Concentrations in Adult Walleye

“…However, it not known how the duration and/or frequency of wet-dry cycles affect Hg levels in specific water-bodies, because limnological conditions and water cycles vary between lakes. Increased Hg concentrations measured in fishes following water level fluctuations could be associated with the frequency of inundation (Sorensen et al 2005). Increased sulfate levels, caused by the drying and rewetting of soils, enhance sulfate reducing bacteria that produce MeHg.…”

“…In this study, we document changes in lake surface area for glacial lakes in the Prairie Pothole Region and relate this to Hg concentration in adult walleye (Sander vitreus). Although a similar phenomenon is known to occur in reservoirs with fluctuating water levels (Jackson 1988;Snodgrass et al 2000;Sorensen et al 2005), widespread effects of surface area changes on Hg concentrations in fishes have not been documented in natural, glacial lakes. We hypothesized that increases in lake surface area enhanced Hg methylation and resulted in elevated fish Hg concentrations.…”

Geochemical legacies and the future health of cities: A tale of two neurotoxins in urban soils

“…The identification of this urban pollution memory for streams is not new (e.g., Gray, 2000;Neumann et al, 2005), but it might be especially problematic for Hg. Many conditions need be present to cause high methylation rates, but the combination of high Hg, high organic matter, and numerous impoundments all contribute to a higher potential for MeHg production (Mason et al, 1994;Macalady, 2000;Seigneur et al, 2004;Sorensen et al, 2005) and thus a higher risk to anglers if they consume certain fish from even these rural stretches of the river (Munthe et al, 2007;Scudder et al, 2009). Crewe (2012), utilized a broad soil sampling scheme to characterize Hg concentrations throughout central Indiana and to further explore the link between regional patterns and a cluster of large Hg emissions sources in southwestern Indianapolis.…”

Mercury bioaccumulation in the food web of Three Gorges Reservoir (China): Tempo-spatial patterns and effect of reservoir management

“…THg concentrations in aquatic organisms exhibited significant difference across sampling seasons (MANOVA, F = 11.93, p b 0.01, Supplementary Table S5 Fuling 13.0 ± 0.3 7.5 ± 0.5 5.7 ± 0.5 5.3 ± 0.5 43 ± 7.3 30 ± 4.2 33 ± 2.1 37 ± 7.1 Wanzhou 11.7 ± 0.4 4.2 ± 0.3 5.2 ± 0.2 4.9 ± 0.2 31 ± 6.4 28 ± 6.2 24 ± 4.8 25 ± 5.7 Zigui 8.5 ± 0.5 5.9 ± 0.2 4.4 ± 0.1 3.8 ± 0.2 20 ± 5.1 16 ± 3.4 14 ± 5.1 10 ± 2.4 Table 3 Comparison of THg concentration (mean or mean ± SD) in the water column, sediment and fish from selected studies (The species code was in accordance to Supplementary (Snodgrass et al, 2000;Sorensen et al, 2005). In Nov. 2011, the water-levelfluctuating zone with external organic matter was inundated, which could activate microbial activity to increase methylmercury production (Sorensen et al, 2005). On the other hand, temporal variation of Hg level could be associated with the frequency of inundation (Ye et al, 2011).…”