FACTORS AFFECTING MERCURY CONCENTRATIONS IN 3 SPECIES OF STREAM SALAMANDER IN GARRETT COUNTY, MARYLAND

Abstract

I sampled 9 streams in Western Maryland during the spring, summer and fall of 2010. 5 species of stream salamander were collected at these streams and analyzed for total mercury; northern dusky salamanders (Desmognathus fuscus), northern two-lined salamanders (Eurycea bislineata), Allegheny Mountain dusky salamanders (Desmognathus ochrophaeus), seal salamanders (Desmognathus monticola), and eastern red spotted newts (Notopthalmus viridescens). The streams were also analyzed for various water chemistry factors; pH, Acid Neutralizing Capacity (ANC), Total Mercury (THg), Methyl Mercury (MeHg), Chloride (Cl-), Nitrate (NO3-), Sulfate (SO42-), Total Suspended Solids (TSS), and Dissolved Organic Carbon (DOC).

In all but two streams adult northern two-lined salamanders had significantly higher concentrations of total mercury in their tissues than larval northern two-lined salamanders. Adult northern two lined salamanders also had the highest concentrations of the three species that were statistically analyzed; northern two-lined salamanders, northern dusky salamanders, and Allegheny Mountain dusky salamanders. Stream methyl mercury concentrations and stream DOC were also found to significantly influence salamander tissue total mercury concentrations.