Freshwater mussel salvage and relocation at the Pond Eddy Bridge, Delaware River, New York and Pennsylvania

In a study conducted by the U.S. Geological Survey, in cooperation with the Pennsylvania Department of Transportation, freshwater mussels were salvaged and relocated from the anticipated zone of impact for the Pond Eddy Bridge construction project in New York and Pennsylvania. Five 25-meter (m) by 25-m cells along the Pennsylvania bank of the Delaware River were sampled in three generally straight-line passes by four surveyors wearing snorkel gear for a total of 180 survey minutes per cell. All mussels encountered were collected and identified to species. A subset of individuals was marked with shellfish tags, weighed, and measured prior to relocation upstream from the zone of impact. A total of 3,434 mussels, including 3,393 Elliptio complanata (eastern elliptio mussels), 39 Anodonta implicata (alewife floaters), 1 Strophitus undulatus (creeper), and 1 Pyganodon cataracta (eastern floater), were salvaged and relocated. All non-eastern elliptio species were georeferenced using a high-resolution global positioning system unit; a subset of tagged eastern elliptio was placed in transects between georeferenced points. These mussels will be monitored to assess the effects of translocation on mortality and body condition at 1 month, 1 year, and 2 years.