Page 12 - The Freshwater Mussels of Oklahoma

effort toward propagation of the commercially valuable species. Two of the resulting
studies include:
Robert Ervin Coker (1897-1967) who worked with others at the U. S. Biological
Station, Fairport, Iowa and published studies on the reproduction and artificial
propagation of unionids.
G. Lefevre and W. C. Curtis also published “Studies on the reproduction and
artificial propagation of fresh-water mussels” (1912).

1970’s Through 1990’s

With the development of plastics in the 1930’s and 1940’s, the shell button
industry collapsed. Plastics were easier to deal with, easily molded to any shape and at
least as durable as mussel shell. Little interest was shown for freshwater mussels during
the next couple of decades. Eventually, there began a movement toward a re-evaluation
of the taxonomy and systematics of unionids. A better understanding of the distributions
of the many species in North America was sought. Among the principle authors during
this period are:
Arthur H. Clarke was with the National Museum of Natural Sciences, Ottawa,
Canada and Associate Curator, Smithsonian Institution before creating a private mollusk
research consultation service.
John B. Burch of the Department of Mollusks, Museum of Zoology, University of
Michigan is responsible for the Environmental Protection Agency Identification Manual
“Freshwater Unionacean Clams (Mollusca: Pelecypoda) of North America.” This was
later revised and re-published.
Richard I. Johnson is with the Museum of Comparative Zoology, Harvard
University and contributed primarily to the history of the Unionidae and zoogeography.
David Honor Stansbery has retired from the Museum of Zoology, Ohio State
University and has written extensively on zoogeography, ecology and evolution of
freshwater mussels.

Recent Studies

During the past couple of decades, and even extending back to the 1960’s, and
especially since the organization of the EPA and the passage of the Endangered Species
Act, there has been a renewed interest in the ecology of unionids and methods of
conservation. This has come about as the scientific world began to realize that unionid
populations were rapidly declining and many species and populations were already
extinct. The effects of an expanding human population in North America and the
environmental degradation associated with their activities, has resulted in devastation of
mussel faunas. In the meantime, a resurgence in harvesting mussel shell has occurred as
the Japanese market for “seed shell” for cultured pearls has expanded. As a result of these
problems, the expanding unionid literature now is focused primarily on the recovery and
maintenance of mussel populations. Much of this interest is reflected in publications

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