Relating Impoundment Morphometry and Water Quality to Black Crappie, Bluegill, and Largemouth Bass Populations in Iowa

摘要

We evaluated the influence of lake morphometry, water quality, and common carp Cyprinus carpio and largemouth bass Micropterus salmoides population structure on quality black crappie Pomoxis nigromaculatus and bluegill Lepomis macrochirus populationsfor 20 Iowa impoundments. Growth of black crappie was positively related to growth of largemouth bass. Black crappie catch per unit effort (CPUE) was positively associated with watershed size and alkalinity and negatively related to largemouth bass growth. Size structure of bluegill populations was positively influenced by chlorophyll concentrations and large-mouth bass catch rates. Total phosphorus and CPUE of stock-to-quality length largemouth bass were also positively related to bluegill growth. Bluegill CPUE was inversely related to largemouth bass growth. Quality largemouth bass populations were allied with turbid (high total suspended solids and low Secchi disk depth) impoundments that had a diverse shoreline and large watersheds. Large-mouth bass growth was inversely related to mean depth, and largemouth bass CPUE was inversely related to alkalinity and total suspended solids. Information from this study will be used to classify and rank impoundments in terms of their management priorities. Based on impoundment morphometry and water quality, managers can then target management practices toward species best suited to a particular impoundment.