Effects of watershed heterogeneity on mercury bioavailability in lotic salamanders [Draft]
Bank MS, Loftin CS, Haines TA, Jung RE. 2004. Effects of watershed heterogeneity on mercury bioavailability in lotic salamanders [Draft]. Acadia National Park
From the abstract: "Mercury (Hg) bioaccumulation in salamanders has received little attention despite widespread Hg contamination of aquatic ecosystems and worldwide amphibian declines. Here we report concentrations of methylmercury (MeHg) and total Hg in larval northern two-lined salamanders (Eurycea bislineata bislineata) collected from streams in Acadia National Park (ANP), Maine, Bear Brook Watershed (BBWM; a paired, gauged watershed treated with bimonthly applications (25kg/ha/yr) of ammonium sulfate [(NH4)2So4]) since 1989), Maine and Shenandoah National Park (SNP), Virginia. MeHg comprised 73-97% of total Hg in the larval salamander composite samples from ANP. At BBWM we detected significantly higher total Hg levels in larvae from the (NH42SO4 treatment watershed. At ANP, total Hg concentrations in salamander larvae were significantly higher in streams in unburned watersheds in comparison to larval samples collected from streams located in watersheds burned by the 1947 Bar Harbor fire. Additionally, total mercury levels were significantly higher in salamander larvae collected at ANP than in samples collected from SNP. Our results suggest that watershed-scale attributes including fire history, whole-catchment (NH4)2SO4 additions, wetland extent, soil properties, and forest cover type influence mercury bioavailability in salamanders inhabiting lotic environments. Use of this species as an indicator of Hg bioavailability in stream ecosystems is also proposed."
- Type
- Published Report
- Authors
- Bank, Michael; Loftin, Cynthia; Haines, Terry; Jung, Robin
- Date of Issue
- 2004
- Units
- ACAD , SHEN
- Keywords
- Mercury (Hg), Mount Desert Island, Pollutants, Precipitation, Rivers & Streams, Salamanders (Caudata), two-lined salamander (Eurycea bislineata), Watersheds