Phase 1 freshwater mussel survey and comparison to historical surveys at the Pond Eddy bridge, Delaware River, New York and Pennsylvania

A qualitative freshwater mussel survey was conducted in a section of the main stem Delaware River near the Pond Eddy Bridge site, New York and Pennsylvania, during summer 2011 to assess population levels of state and Federal threatened and endangered species. Historical data that were collected at this site were compared to data from the 2011 survey to assess changes in mussel community composition and differences in survey methodology. A total of 4,080 mussels of three species - Elliptio complanata, Anodonta implicata, and Strophitus undulatus - were sampled at the Pond Eddy Bridge site in 2011. No mussel species (Alasmidonta heterodon or Alasmidonta varicosa) that are on Federal or state lists of threatened or endangered species or their shells were collected in this survey. These results are comparable to historical surveys at the site, with some differences in estimated catch per unit effort (CPUE) and species detection, depending upon survey methodology. The CPUE of the three species and species richness and diversity were evaluated. The percentages of species composition for A. implicata, E. complanata, and S. undulatus were 0.02, 0.97, and 0.002, respectively, in 2011.