DAVID DEREK ADAY AND D. ALLEN RUTHERFORD, Cooperative Fish and Wildlife Research Unit, School of Forestry, Wildlife, and Fisheries, Louisiana State University, Baton Rouge, Louisiana 70803, USA

The Atchafalaya River Basin (ARB) in southern Louisiana is North America’s largest bottomland hardwood swamp. The ARB supports a variety of different habitats, which become markedly different physicochemically throughout the year. Temporal changes result in widespread hypoxia throughout the Basin. Our research focused on the effect of hypoxia on instantaneous growth of bluegill Lepomis macrochirus. We measured RNA-DNA and protein-DNA ratios, which have been shown to be sensitive indicators of short-term growth in fishes. Our objectives were to: 1) determine the effect of hypoxia on instantaneous growth by comparison of RNA-DNA and protein-DNA ratios of bluegill collected in hypoxic and normoxic waters of the ARB, and 2) test the effects of starvation and hypoxia on the RNA-DNA and protein-DNA ratios of bluegill through controlled laboratory experimentation. Bluegill were collected by electrofishing in both oxygen rich and hypoxic areas of the ARB. Dorsal epaxial muscle samples of approximately 200 mg were taken from each fish and stored in liquid nitrogen. A total of 57 fish were collected from both water types. We predict RNA-DNA and protein-DNA ratios will be significantly lower in bluegill collected from hypoxic water, indicating slower growth in these fish.