Poster Presentation Symposium on Urbanization and Stream Ecology 2025

Mussel response to dam removal: a synthesis of survey approaches and findings (#45)

Alexa Hershberger 1 , Allison Roy 2 , Ayla Skorupa 3 , Jason Carmignani 4
  1. Organismic and Evolutionary Biology Program, University of Massachusetts Amherst; Massachusetts Cooperative Fish and Wildlife Research Unit, Amherst, MA, USA
  2. U.S. Geological Survey, Department of Environmental Conservation, University of  Massachusetts Amherst, Massachusetts Cooperative Fish and Wildlife Research Unit, Amherst, MA, USA
  3. Illinois Natural History Survey, University of Illinois at Urbana-Champaign, Urbana, IL, USA
  4. The Natural Heritage and Endangered Species Program, Division of Fisheries and Wildlife, Westborough, MA, USA

Historically, dams have provided important economic resources (e.g., textiles, mills, hydroelectric power),yet, many dams are no longer needed for these tasks, leaving them abandoned and unregulated. In urban systems, these dams may exacerbate risks to freshwater ecosystems and human health and safety due to urban stream syndrome (e.g., flashier hydrograph, elevated pollutants, altered channel morphology). Dam removal has become an attractive stream restoration strategy; however, some dam removals may harm surrounding biotic communities due to sediment mobilization, high flows, and rapid water level declines during the removal, especially impacting species that are relatively sessile like freshwater mussels. Studies documenting mussel responses to dam removal are limited, but information gained from past studies can help to improve future monitoring. Here, we conducted a global review of scientific and grey literature investigating the impacts of dam removal on mussels. We collected information on dam removal strategies (e.g., phased removals), survey designs, sampling methods, habitat characteristics, and mussel response. Findings from our synthesis highlight the current status of mussel dam removal literature, creating an opportunity for researchers to improve monitoring efforts across systems. Moreover, the synthesis may identify ways to minimize impacts to freshwater mussels in vulnerable systems, such as urban waterways.