Spatial patterns and temporal trends in atmospheric deposition, surface water and fish mercury in the Adirondack region of New York

Charles Driscoll1, Stephen Boucher2, Jacqueline Gerson3, Mariah Taylor4, Amy Shaw5 and Eric Paul6

While the Adirondack region of New York experiences modest atmospheric mercury deposition, it is considered a biological mercury hotspot. Wet and litter mercury deposition, and stream and lake mercury are monitored at Huntington Forest in the central Adirondacks through NADP.  We have not found changes in wet mercury deposition since measurements were initiated in 2000, but litter mercury appears to be decreasing. Arbutus Lake inlet and outlet samples at Huntington Forest show long-term decreases in concentrations and fluxes of both total and methyl mercury, despite increases in dissolved organic carbon. More broadly we have examined spatial patterns of mercury in standard length yellow perch (Perca flavescens) across Adirondack lakes.  We find elevated concentrations of mercury in fish, particularly in the western Adirondack.  Mercury concentrations in yellow perch are particularly elevated in lakes with low pH and acid neutralizing capacity.  Fish mercury concentrations also increase with total and methyl mercury concentrations and monomeric aluminum fractions.  We did not observe any relationship between fish mercury and lake concentrations of dissolved organic carbon, although we did find strong correlations between total and methyl mercury concentrations and dissolved organic carbon in the water column.  Finally, there are 17 Adirondack lakes with multiple year observations of fish mercury in yellow perch dating back to the early 1990s.  Trend analysis indicates that all but one of these lakes are showing statistically significant decreases in mercury concentration at a mean rate of 0.007+0.004 µg g-1 ww.

 

1Syracuse University, ctdrisco@syr.edu
2Syracuse University, sebouche@syr.edu
3Syracuse University, jgerson1@gmail.com
4Syracuse University, mstayl01@syr.edu
5Syracuse University, alshaw01@syr.edu
6NYS DEC, eapaul@gw.dec.state.ny.us