Influence of Environmental Variables and Species Interactions on Sport Fish Communities in Small Missouri Impoundments

Abstract

Small impoundments (<400 ha) are numerous and provide close‐to‐home fishing opportunities for anglers but may not support optimal sport fisheries. Most of these fisheries are managed by harvest regulations, but watershed and impoundment characteristics, poor water quality, or detrimental species interactions can also influence the desirability of fisheries. We examined the relative importance of watershed characteristics, impoundment morphology, water quality, and species interactions in explaining differences in relative abundance, growth, and size structure of five sport fish species (largemouth bass Micropterus salmoides, bluegill Lepomis macrochirus, redear sunfish L. microlophus, white crappie Pomoxis annularis, and black crappie P. nigromaculatus) among 89 small Missouri impoundments spanning a large fertility gradient. Using regression analysis, we found that variables associated with predation, competition, and lake fertility were most important in explaining variation in sport fish demographics, whereas watershed and impoundment morphology variables were typically less important. Lakes with dense largemouth bass populations commonly contained sunfish and crappie populations with desirable size structure and growth, implying that predation was a strong structuring force. Density‐dependent growth was common among all sport fish species. White crappies and black crappies had better growth or size structure in lakes with fewer bluegills, suggesting competition among these species. Lakes containing common carp Cyprinus carpio had fewer largemouth bass and slower‐growing black crappies than lakes without common carp. The presence of gizzard shad Dorosoma cepedianum benefited largemouth bass populations but negatively affected bluegill and black crappie populations. Growth and size structure of sport fishes usually improved with increasing lake fertility. Predation and competition seemed to be most important in structuring sport fish communities in these impoundments provided that lake fertility was adequate to sustain acceptable abundances and growth rates of these fishes. Received February 10, 2012; accepted August 17, 2012

Interrelationships among bluegill demographics, predator and competitor abundances and impoundment characteristics

“…Bluegill CPUE was positively associated with largemouth bass CPUE and total phosphorus concentration (negative correlation with lake PC1). Michaletz et al (2012) and Bevil and Weber (2018) also found a positive relationship between the relative abundances of bluegills and largemouth bass; likely because both species have successful recruitment under similar environmental conditions. Bluegill has been found to be more abundant in more-productive waters than in less-productive waters (Aday et al 2003a;Michaletz et al 2012).…”

“…Surprisingly, gizzard shad CPUE was not included in the top models explaining TL95 of bluegill and was not correlated (all p> 0.39) with any bluegill TL variable. Water body productivity as indexed by Secchi depth, chlorophyll or total phosphorus has been associated both positively (Tomcko and Pierce 2001;Schultz et al 2008;Hoxmeier et al 2009;Michaletz et al 2012) and negatively (Hoxmeier et al 2009) with bluegill growth and size structure. The TL and age of bluegills at sexual maturity was positively associated with clearer water (greater Secchi depths).…”

“…In addition to the potential mechanisms listed above, bluegill populations are influenced by numerous other factors. Water body characteristics such as water clarity, water temperature, productivity, macrophyte coverage, morphometry, watershed area, prey abundance and others have been associated with bluegill demographics Pierce 2001, 2005;Paukert et al 2002b;Cross and McInerny 2005;Hoxmeier et al 2009;Michaletz et al 2012;Bevil and Weber 2018). Fish community characteristics also shape bluegill populations.…”

Bolstering Piscivore Abundance to Restructure Small Impoundment Fish Communities

“…Lakes (and abbreviations) highlighted in bold are treatment lakes followed by their respective reference lakes. Morphometric and mean water quality data are from Knowlton and Jones (2007); Jones et al (2008b); Michaletz et al (2012); the Limnology Laboratory, University of Missouri (unpublished data); and the Missouri Department of Conservation (unpublished data). Macrophyte coverage shows the means from this study (T = trace).…”

Variable Length at Age for Black Crappies and White Crappies in Missouri Small Impoundments

“…Likewise, the equation for White Crappies was Morphometric and water quality variables for the crappie study lakes in Missouri (BLC = Black Crappie; WHC = White Crappie). Morphometric and water quality data are fromKnowlton and Jones (2007);Jones et al (2008);Michaletz et al (2012b); the Limnology Laboratory, University of Missouri (unpublished data); and the Missouri Department of Conservation (unpublished data).…”