To return to the Northeast Fish & Wildlife Conference website, go to: http://www.neafwa.org/conference.html. The following schedule and room names are subject to change (as of April 3, 2017). Please check back for updates. Session titles marked with an asterisk (*) have student presenters.
AUTHORS: Valerie Watson, Pamela Wells, Melissa Smith - University of Maine
ABSTRACT: The responses of invertebrate communities and leaf decomposition to urbanization is well understood at the scale of whole rivers, but very few studies have addressed the possibility of differences in response between habitat types within rivers. We investigated whether urbanization influenced invertebrate communities and leaf decomposition rates in central Maine streams differently in high versus low velocity habitats. We used leaf bags of red maple (Acer rubrum) to measure invertebrate community composition and leaf breakdown rates in the pools and riffles of six streams along a gradient of catchment impervious cover (IC) spanning from < 1% IC to more than 50% in the most heavily developed watersheds. Physical variables remained fairly constant along this gradient in both habitat types, but more urbanized streams had significantly fewer EPT taxa and significantly more non-insect taxa than their less impacted counterparts. In addition, urbanized pools had considerably higher overall abundance and taxonomic richness than natural pools, while riffles saw the opposite trend. Urbanization had no major effect on leaf breakdown rate, but leaves in riffles decomposed faster than those in pools. These results suggest it is important to consider differences in habitat response when looking at the response of stream ecosystems to urbanization.
