The following bar graph shows the relative abundances of all the species of live mussels found in the Cannon River.
Lampsilis siliquoidea was by far the most abundant species in our ten meter searches. The six species we found were one more than Davis found in 1987; Ligumia recta represents the extra sixth species. The substrate at this site was primarily gravel. Some of the populations we located were very high density (>1/m2). Interestingly, mussel distribution in our high density areas was even across the stream, even up under the grassy banks. Search technique was crucial in this stream, or mussels located back under the grassy banks would be missed. We were only able to complete 5x 10m sections because of the large numbers of individuals we were loacting.
The Cannon near Morristown is a moderate-velocity river carrying an extremely high algal load. Shells removed from the stream were caked in algae, making identification difficult at times. Visibility is zero for searching; searches must be done by feeling through the top 1cm of sediment.