We are working to develop an integrated and calibrated indicator of ecological integrity for forested headwater streams in the Mid-Atlantic states. Ecological indicators provide a quick, objective, and relatively easy method to gauge the condition of a particular resource, and aid greatly in the establishment of conservation priorities and development of restoration goals. Headwater systems are degraded by point source stressors, like acid mine drainage, and also by more cumulative and insidious stressors that operate at large scales, such as forest fragmentation.
Ecological indicators exist that respond to site-level attributes, like water quality.
We studied LOWA on forested headwater streams in three physiographic provinces of Pennsylvania between March and July 2000. Low water quality in our sample streams is due to low pH, primarily resulting from acid mine drainage in southwestern Pennsylvania. We were particularly interested in documenting nest predation levels in 2000, for comparison to the apparently elevated levels we observed in 1999. Our observations in 2000 indicate that the high nest predation rates observed in 1999 were indeed anomalous. Figure 1 illustrates fledging success in all three study areas over the 3-year sampling period for this project.