Fish and Benthic Macroinvertebrate Assemblage Response to Removal of a Partially Breached Lowhead Dam

Dam removal is an increasingly common restoration technique in lotic ecosystems. Potential dam removal benefits include improved aquatic organism passage, restoration of natural flow dynamics and a general improvement in habitat for native species. However, understanding potential dam removal outcomes requires data on ecosystem response in a wide variety of settings. We evaluated fish and benthic macroinvertebrate response to removal of the Spruce Pine dam in western North Carolina, USA. This dam was partially breached prior to removal, and impounded a coolwater river, both scenarios under which dam removal has been under‐studied. Post‐removal shifts in fish and benthic macroinvertebrate assemblages did not occur, suggesting that previously documented patterns of assemblage change in response to dam removal, particularly in the area upstream from the dam, are not universal, and may depend upon factors such as river gradient and water temperature, and the available species pool. Such information can aid managers in identifying conditions under which an expectation of significant instream habitat improvement in response to dam removal may not be warranted. Copyright © 2016 John Wiley & Sons, Ltd.