78 Paul W. Parmalee, Walter E. Klippel, Arthur E. Bogan 



from the surface of the eroding shell banks and beaches, but a special 

 effort was made to recover all such cultural material found within the 

 portions of undisturbed shell lenses that were removed for this study. 

 Since many of the deposits were comprised of residue from several cul- 

 tural groups that spanned a considerable period of time, only those 

 sherds and other artifacts found in direct association with the selected 

 samples were used to define the temporal periods involved. 



Considerable variation in midden size was apparent, with some 

 containing only a few hundred valves and others literally hundreds of 

 thousands. Most also contained shells of freshwater gastropods. Because 

 of the typically compact nature of the shell lenses, we could remove only 

 a small part of the shell comprising the midden and yet obtain a large 

 but relatively unbiased sample of the species assemblage. All samples 

 were returned to the Department of Anthropology, University of 

 Tennessee, Knoxville, where the shell was washed and determinations of 

 species were made by comparisons with fresh specimens in the Zooar- 

 chaeology Section mollusk collection. Approximately 40,500 freshwater 

 mussel valves, representing about 50 species, were identified from the 

 samples collected during this study. For this report we evaluated collec- 

 tions from 15 of the sites (Fig. 2) for which the temporal assessment was 

 most exact; samples from these 14 sites consisted of 27,875 valves. All 

 specimens recovered during this study are housed in the Zooarchaeol- 

 ogy Section, Department of Anthropology, University of Tennessee, 

 Knoxville. 



RESULTS AND DISCUSSION 



Present Status of Naiad Fauna in Middle and Upper Chickamauga 

 Reservoir 



During the past two decades several investigators attempted to 

 determine the status of freshwater mussel populations inhabiting the 

 middle and upper Chickamauga Reservoir from ca. TRM 495 to TRM 

 529 (Scruggs 1960; Isom 1969; Pardue 1981). The study by Scruggs 

 (1960) was undertaken primarily to determine the abundance, effects of 

 shelling operations, and potential for recovery of commercially valuable 

 species, especially Pleurobema cor datum (Raf. 1820), on specific beds in 

 the Tennessee River (Wheeler and Chickamauga reservoirs). Although 

 also concerned with similar aspects of naiad ecology and economics, the 

 comprehensive study by Isom (1969) provided a more complete assess- 

 ment of the total mussel fauna assemblage and evaluated the factors 

 that brought about changes in extant species and population abundance 

 since impoundment. 



On the basis of these studies approximately 20 species (synonymiz- 

 ing Anodonta corpulenta Cooper 1834 with Anodonta grandis Say 



