Robert B. Row and Frank J. Bulow, Department of Biology, Tennessee Technological University, Cookeville, TN 38505

Abstract. As reservoirs age, they often lose woody habitat that may be essential cover for successful fish reproduction. The purpose of this study was to evaluate the use of spawning benches to increase smallmouth bass (Micropterus dolomieu) spotted bass (Micropterus punctulatus), and largemouth bass (Micropterus salmoides) production. In 1996, United States Army Corps of Engineers personnel and volunteers installed 80 spawning benches in two test coves of Holmes Creek Embayment of Center Hill Reservoir. Each spawning bench consisted of an 8 - 10 ft (2.4 - 3.0 m) slab of oak attached to two or three 8" or 12" (20.3 - 30.4 cm) cinder blocks laid on the shoreline. Benches were placed at various elevations and either parallel or perpendicular to the shoreline. Spawning benches were intended to provide cover under which fish could spawn. During the spring, summer, and fall months of 1996 and 1997, we evaluated the use of these spawning benches. SCUBA gear was used to dive 100-m transects in both test and control coves for observation of fish nesting. Micropterus species were observed using 66% of the benches for nesting (27 nests at the 41 spawning benches observed). Spotted bass were observed using the benches for nesting 16 times (39% use), smallmouth bass 9 times (22%), and largemouth bass twice (5%). Spotted bass preferred a soft substrate, a gradual slope (21-30%), 12" block size, and a perpendicular arrangement of the benches. Smallmouth bass preferred hard substrate, a gentle slope (13-20%), 12" block, and a parallel arrangement. No preference was determined for largemouth bass because only two nests were found. Nighttime shoreline electrofishing was conducted for the months of July, August, and September of 1995-1997 to compare young-of-year densities in test and control coves prior to and after bench installation.