Contribution of stocked advanced-fingerling largemouth bass to the population and fishery at Taylorsville Lake, Kentucky

摘要

Fin-clipped largemouth bass Micropterus salmoides averaging 4.2-4.5 in long were stocked annually in 3,050-acre Taylorsville Lake in the fall from 1988 to 1992 at densities ranging from 9.8 to 27.8 fish/acre. Survival of each year-class of stocked largemouth bass from age 0 to age 5 was similar; however, survival from the time of stocking to fall collection varied among year-classes, which suggests density dependence in survival. Optimal stocking density ranged from 9.8 to 12.8 fish/acre based on higher survival and lower production costs. In 1993, after 5 years of stocking, the stocked largemouth bass accounted for 37.6% (<8.0 in), 18.2% (8.0-11.9 in), 24.1% (12.0-14.9 in), and 14.9% (>=15.0 in) of the various size-groups and 24.5% of the total electrofishing catch. Contribution of the stocked largemouth bass in the electrofishing catch declined to below significant levels by the second spring after cessation of the fall stocking program. Corresponding significant increases were detected in the estimated anglers' catch and release of 8.0-11.9-in largemouth bass. Stocked largemouth bass accounted for an estimated 14.4% of the total number of 12.0-14.9-in fish and 11.5% of the total number of 15.0-in and larger fish caught and released by anglers from 1990 to 1995. Stocked largemouth bass did not result in significant increases in total numbers of bass harvested, however, they did account for 11.6% of the legal harvest of bass at the lake from 1990 to 1995. Contribution of stocked bass to the fishery declined rapidly after 1995, 3 years after stocking ceased. The 5-year largemouth bass stocking program at Taylorsville Lake provided benefits to both the population and fishery and resulted in a cost: benefit ratio of 1:3.9 for the catch-and-release portion of the fishery from 1990 to 1995.