Meeting Abstract
Acid mine drainage (AMD) constrains within-stream trophic linkages and has negative effects on freshwater ecosystems. The extent to which AMD affects higher trophic levels in riparian ecosystems is not well known. Additionally, it is unknown how AMD affects the ecomorphological relationships between stream and riparian ecosystems. Some terrestrial organisms that normally acquire nutrients from stream may either avoid or be excluded from polluted areas. If true, then AMD potentially constrains cross-ecosystem energy transfer, and may influence the emergent properties of biological organization such as population densities, community membership, and functional ecomorphological relationships. Our goals were to 1) explore the similarities and differences between AMD and non-AMD bird community membership, 2) test for numerical responses in aerial insectivores along those tributaries and 3) determine if there is a morphological, and hence functional loss these AMD affected streams. We conducted bird and nest surveys along tributaries of the Susquehanna River with varying degrees of AMD pollution. We characterized and compared the morphological space of bird communities of AMD and non-AMD streams. Analysis of variance, Monte-Carlo null-community analysis, and non-parametric statistical tests indicate there are fewer species, particularly piscivores and insectivores in AMD stream reaches. Aerial insectivore nesting was less dense and the morphological diversity of AMD streams was negatively affected. The latter result suggests pollutants such as AMD may preclude the capacity for ecomorphological relationships to form along these streams. Acid mine drainage affects the emergent properties of bird communities (e.g. species richness), and potentially more important, negatively affects functional cross-ecosystem dynamics and watershed quality.
