Bluegill population demographics as related to abiotic and biotic factors in Florida lakes

Andrew Kenneth Carlson; Mark V. Hoyer

doi:10.3390/fishes8020100

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Bluegill population demographics as related to abiotic and biotic factors in Florida lakes

Andrew Kenneth Carlson·Mark V. Hoyer

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Abstract

Research on Bluegills, Lepomis macrochirus R., is abundant but typically focuses on water bodies with similar environmental conditions. We assessed Bluegill density, relative abundance (catch per unit effort [CPUE] by electrofishing), growth, and size structure in 60 lakes with wide-ranging surface areas (2–12,412 ha), trophic states (oligotrophic–hypereutrophic), and macrophyte abundances (0.3–100 percent of lake volume inhabited [PVI]) across Florida, USA. Bluegill density and CPUE increased with lake productivity and decreased with macrophyte abundance. Bluegill growth increased with lake productivity and CPUE of stock-length Florida Bass, Micropterus floridanus L., a Bluegill predator. Bluegill size structure increased with lake productivity and decreased with Bluegill density. Results indicate that Bluegill fisheries with abundant individuals of quality size (≥150 mm) require productive (>25 μg/L chlorophyll- a concentration) lakes with moderate to high macrophyte coverage (PVI 50–100), abundant stock-length Florida Bass (>40 fish/h of electrofishing), and Bluegill densities <300 fish/ha. This study provides an approach to predict Bluegill population demographics based on abiotic and biotic factors, establish fisheries management expectations, and develop regional and lake-specific management tools.

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Source-reported bounding extent: 24.544701° to 31.000888° latitude; -87.634938° to -80.031362° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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BibTeX RIS

Andrew Kenneth Carlson, Mark V. Hoyer. 2023-02-07. Bluegill population demographics as related to abiotic and biotic factors in Florida lakes. https://doi.org/10.3390/fishes8020100

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