Forests play a major role in maintaining healthy streams and in providing ecosystem services such as clean drinking water, flood/drought protection and biodiversity, but studies have shown that some forestry operations can compromise these benefits. To assess whether current forest management practices impact stream ecosystems, a five-year study was conducted in J.D. Irving, Limited’s Black Brook Forestry District (New Brunswick, Canada) and in other watersheds with varying forest management intensity. This study was divided into two phases, with each addressing one main research question: 1) how different intensities of forest management affect the ecological health of headwater streams and, 2) whether the changes observed in headwater streams accumulate or dissipate in larger downstream rivers. A comprehensive approach to examining these research questions was taken by measuring multiple …