Contribution of Largemouth Bass Reared in Nursery Ponds to Year Classes in Two Texas Reservoirs

Genetically-marked Florida largemouth bass (Micropterus salmoides floridanus) fingerlings with rare or unique genotypes were stocked into nursery ponds at Lake Conroe (8,484 ha) and Lake Gladewater (323 ha). Following grow-out, advancedsize individuals were stocked into respective reservoirs. We measured the contribution of stocked individuals to corresponding year classes in receiving reservoirs. Largemouth bass survival in nursery ponds at the end of the grow-out period was 15.6% at Lake Conroe and 20.9% at Lake Gladewater. A total of 2.8 fish/ha (mean total length = 138 mm) were stocked in Lake Conroe and 8.8 fish/ha (mean total length = 121 mm) were stocked in Lake Gladewater. Following reservoir stockings, largemouth bass populations were sampled with electrofishing gear in fall and spring and electrophoretic analysis was conducted to evaluate the contribution of stocked fish to corresponding year classes. Largemouth bass from nursery ponds comprised 0.0%, 5.0%, and 0.0% of the 1991 cohort at Lake Conroe in October 1991, April 1992, and November 1992 electrofishing samples, respectively. Largemouth bass from Lake Gladewater nursery ponds comprised 4.5%, 6.7% and 0.0% of the 1992 cohort in December 1992, March 1993, and March 1994 electrofishing samples, respectively. Returns from nursery pond stockings were low with minimal contribution to year classes in study reservoirs.

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Starting page
131
Ending page
138
ID
19394