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Geology topics

Tyler Steven Coleman

Publications and source records attributed to Tyler Steven Coleman.

2 recordsLinked to original sources

Evaluation of shoreline rotenone application to control Largemouth Bass recruitment in small impoundments

Objective Reducing Largemouth Bass Micropterus salmoides recruitment and therefore population density could benefit recreational fisheries in small impoundments by improving individual growth rates and increasing the average size and condition of Largemouth Bass. To achieve these effects, methods of controlling Largemouth Bass recruitment should avoid reducing the productivity of their primary prey species, the Bluegill Lepomis macrochirus . Methods We tested this hypothesis by evaluating the effects of shoreline rotenone application on the density of Bluegill and the density, growth, and survival of age-0 and age-1 Largemouth Bass in 15 Alabama small impoundments. Result After treatment, Largemouth Bass age-0 densities declined and mean age-1 length increased, whereas Bluegill populations were not significantly reduced. Conclusion Our study indicates that shoreline rotenone application may be a valuable method for reducing Largemouth Bass recruitment and increasing the growth of age-1 Largemouth Bass in small impoundments. However, further research is needed to understand the effects of treatment on nontarget fishes and to better assess the effects of factors such as impoundment surface area and treatment frequency and duration on the ultimate utility of the approach.

Alabama

Characterization of fish assemblages in eleven multi-use reservoirs from North Carolina, USA

Managing impounded river systems is a recurring challenge for aquatic resource professionals because reservoirs serve multiple functions with different ecological and socioeconomic outcomes. However, research on fishes in reservoirs has disproportionally focused on recreationally and economically important species, with less attention directed toward fish assemblages despite the potential for management at the assemblage level. As such, evaluation of relationships between reservoir fish assemblages and biotic and abiotic factors and testing whether assemblage structure is affected by changing environmental conditions may deepen ecological understanding and provide insights for reservoir fisheries management. Our overall objective was to assess these relationships in 11 reservoirs from North Carolina, USA. We sampled fish assemblages in the reservoirs, which spanned five river basins representing a range of habitat conditions, using experimental gillnets and pulsed DC nighttime electrofishing. Multivariate statistical analyses indicated that taxonomic differences in fish assemblage composition among river basins followed a gradient of productivity. The top contributing species to reservoir dissimilarity were bluegill ( Lepomis macrochirus ), gizzard shad ( Dorosoma cepedianum ), black crappie ( Pomoxis nigromaculatus ), and white perch ( Morone americana ). These four species were positively associated with factors that reflect increasing eutrophic conditions in the 11 reservoirs and could, therefore, serve as indicators of reservoir productivity, anthropogenic influence, and fish assemblage structure, in addition to their key role in reservoir fisheries management. Whereas ­fisheries research has historically focused on assessing fish ­populations, our results illustrate the ecological and management insights derived from simultaneously collecting assemblage- and population-level data. Research on reservoir fish assemblages in relation to biotic and abiotic conditions may help advance fish ecology and management alike.

North Carolina