Comparisons of Reservoir Characteristics with Striped Bass Growth and Relative Weight in the Southeastern United States

摘要

Growth and relative weight (Wr) condition index were estimated for striped bass Morone saxatilis (ages 1-6) from 15 southeastern U.S. reservoirs spanning seven states. On average, striped bass reached quality length for a fishery (510 mm) in about 2.5years. Predicted lengths up to age 6 were highly variable among reservoirs and overlapped among age-classes. Cooling degree-days above 15.5°C was negatively related with growth for ages 2-6 and, when combined with higher water level fluctuation, explained 47-56% of the variation for ages 2-3. For ages 4-6, the best models for growth included increased reservoir volume, reduced retention time, and fewer cooling degree-days, as predictors, explaining 69-74% of the variation. Correlations between growthand W_r were not significant. Relative weights for each reservoir were similar but declined with fish age. Significant relationships between W_r and reservoir age, elevation, mean depth, area, and water level fluctuation only occurred for some ages. In general, physical characteristics used in this study explained only modest amounts of the variation in growth and W_r for the reservoirs we investigated. Our results underscore the complexity of individual reservoir systems and differences among reservoirs when defining expectations for reservoir striped bass populations.