Factors Affecting Growth of an Initial Largemouth Bass Year Class in a New Texas Reservoir

ABSTRACT Highly variable and bimodal length-frequency distributions were observed from an initial young-of-the-year largemouth bass (Micropterus salmoides) year class in Aquilla Lake, a newly impounded reservoir. Spawning distribution, from daily age determination, indicated that early hatched fish in the cohort tended to be larger fish by late summer-early fall. Age accounted for 46% and 43% of the bass length variation in August and October, respectively. By October, lower growth rates were observed for late hatched fish than for older, earlier hatched fish. A paucity of suitable size prey available to the smaller individuals in the cohort probably accounted for differential growth rates. All these factors appeared to contribute to large variation in length for this year class. Recruitment to adult harvestable size is more likely to be achieved by earlier hatched, faster growing age-0 largemouth bass.