Examination of Juvenile and Adult Freshwater Mussel (Bivalvia: Unionidae) Stream Parameter Preferences

Holly N. Blalock
U.S. Geological Survey, Biological Resources Division, Florida Caribbean Science Center, 7920 NW 71st Street, Gainesville, FL 32653, Ph: (352) 378-8181 x 354 Fax: (352)378-4956 E-mail: holly_blalock@usgs.gov

The objective of this study was to determine if juvenile and adult freshwater mussels of Elliptio icterina, Quincuncina kleiniana, Pleurobema pyriforme, from the New River, Suwannee River Drainage, Florida, exhibit stream parameter preferences. The following stream parameters were recorded from 2000 quadrat samples of 0.25m2 each: habitat type, sediment type, relative amount of detritus, and density of an exotic bivalve, Corbicula fluminea. Juvenile E. icterina exhibited a preference for detritus amount and C. fluminea density, while adults exhibited a preference for habitat type, sediment type, and C. fluminea density. Juvenile Q. kleiniana exhibited no preferences, while adults exhibited a preference for habitat type, sediment type, and C. fluminea density. No juvenile P. pyriforme were collected during this study. Adult P. pyriforme exhibited no stream parameter preferences. Pleurobema pyriforme may have stream parameter preferences that remain undetected due to low densities. Stream parameter preferences for different habitat types, sediment types, and detritus amounts may be related to host fish preferences, food availability, water flow and depth, or a combination of these factors. A preference for quadrats with high densities of C. fluminea may indicate a competition for resources.