SCOTT LOFTIS, CHRISTOPHER O’BARA, AND MICHAEL EGGLETON, Tennessee Technological University, Center for the Management, Utilization, and Protection of Water Resources, Cookeville, Tennessee, USA

Age-0 largemouth bass Micropterus salmoides were collected bi-weekly from 22 May through 22 August 1995 using standard backpack electrofishing techniques in littoral areas. Hatching distribution and daily growth rates were determined by examining sagittal otoliths. Hatching duration extended for 68 d from 6 April to 13 June. Hatching success was disrupted for a 10 d period in mid April, when air and water temperatures dropped suddenly. Disjunctive spawning resulted in a bimodal hatching distribution, however no evidence of a bimodal length distribution existed in the fall. Mean growth rates ranged from 1.04 to 0.79 mm/day. A positive relationship was found for total length and age. Growth rates were similar among sub-cohorts age classes and size advantages for larger cohorts resulted from earlier hatching dates. Mid-summer grow rates increased significantly during intervals of decreased habitat complexity attributed to water level drawdown. Early-hatch subcohorts shifted to piscivory at a younger age (50d) than did mid-hatch subcohorts (65d). Late-hatch subcohorts were unable to shift to piscivory.