Abiotic and Biotic Factors Related to Black Bass Fishing Quality in Alabama

ABSTRACT

We used black bass (Micropterus spp.) tournament catch data from 27 Alabama reservoirs collected from 1986 to 1991. These data included nearly 0.5 million angler hours of effort and examined 17 factors possibly related to variation in catch rates and size of black bass caught by anglers. Shoreline length, the shoreline development index, and reservoir surface area were all positively related (r = 0.40 to 0.57; P <0.05) to catch-per-hour of black bass greater than 304 mm total length. Chlorophyll a concentrations, conductivity, reservoir age, and the percent genetic influence of Florida largemouth bass (M. salmoides floridanus) in the largemouth bass population were positive regressors (P < 0.05) of average weight of black bass caught and combined, these variables explained 73% of the variation of this fishery parameter in a multiple regression equation. Similarly, Florida largemouth bass influence, the morphoedaphic index (Ryder 1965), and chlorophyll a were all positive regressors (P < 0.05) of catch rates of memorable-size (≥ 2.27 kg) fish and together, explained 63% of die variation in this term. Our analysis suggested that differences in trophic state ranging from eutrophic to oligo-mesotrophic were not related to catch rates, but were associated with smaller caught fish and greater effort to catch a memorable-size fish. Florida largemouth bass influence, either created through stocking efforts or by natural occurrence, was associated with anglers catching much larger fish, and this was more apparent in eutrophic water bodies. Many reservoir attributes considered in this analysis cannot be directly manipulated to affect black bass fisheries, but recognition of die relations among these variables will assist fishery biologists and limnologists assess die potential for management of black bass fisheries.

Key Words:

• black bass tournaments
• trophic state
• chlorophyll a
• catch-per-effort
• average weight
• memorable-size black bass
• reservoir
• morphometrics
• Florida largemouth bass