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Anderson, R. V., J. W. Grubauch, R. E. Sparks and K. W. Blodgett (1989). Mussels of Pool 19, 75 years behind a dam. Pages 13 in J. Rasmussen, ed. Proceedings of the Mississippi River Research Consortium, La Crosse, Wisconsin (USA), Mississippi River Research Consortium.

The river reach presently designated Pool 19 has long been an area of known mussel beds with history notes dating to the early 19th century. In association with commercial harvest for the pearl button industry and construction [sic] of Dam 19, early researchers predicted a reduction in the mussel populations of the river. Qualitative construction and quantitative records for the past 75 years were examined to determine if changes have occurred and to evaluate those changes in the mussel community. While commercial mussel harvest rapidly declined in the 30's and 40's it has again become a prevalent activity on the river with tons of mussels being removed from the river annually. In 1930, 21 species of mussels were collected from this Pool while in the mid-1980's 29 species were present. Sampling effort and the number of habitats examined increased in the 1980's. Even though simple diversity may have increased, density has decreased. Though more species are presently reported from this river reach, shifts in density and composition have occurred with previously abundant species becoming rare.