Martin W. Brunson

Winter growth of young-of-the-year bluegills (Lepomis macrochirus) and male bluegill X female green sunfish (L. cyanellus) hybrids was compared. After 112 days in ponds with a mean afternoon surface water temperature of 10.4 0 C, and under monospecies and bispecies culture conditions, the hybrids were significantly (P < 0.01) longer and heavier than the bluegiIls, outgrowing the bluegills by a ratio of approximately 2: 1.

The effects of supplemental feeding on the winter growth of male bluegill (Lepomis machrochirus) x female green sunfish (L. cyanellus) F1 hybrids were investigated in northeast Mississippi. Four 0.04 ha ponds were each stocked at the rate of 2471 fish per ha. Fish in 2 ponds were fed daily while the other fish subsisted only on natural food. Mter 90 days at water temperatures below 15 C, fed fish were significantly (P <0.05) heavier. but not longer than non-fed fish. Coefficients of Condition (K) for fed fish showed a significant (P < 0.05) increase through the winter and were...