Centrarchid Assemblages in Mississippi State‐Operated Fishing Lakes

Abstract

We evaluated electrofishing catch per effort in 27 state‐operated fishing lakes in Mississippi to identify patterns of centrarchid community composition and to determine whether those patterns were related to selected environmental characteristics and to artificial nutrient enrichment. Ordination with detrended correspondence analysis recognized two major axes accounting for 77% of the variability in species ordination. Axis 1 showed a distinct separation between the body sizes of various species. A notable exception was the density of small (<30 cm) largemouth bass Micropterus salmoides, which aligned with the large individuals of other centrarchid species. This pattern suggested that through predation, high densities of small largemouth bass exerted significant control over the size structure of fish communities. Axis 2 separated species of crappies Pomoxis spp., suggesting that conditions other than strong species interactions also moderated the composition of crappies in the assemblages. However, neither lake morphometry nor watershed composition exhibited a major influence over axes 1 or 2. In small, intensively managed lakes with low habitat complexity, the regulatory importance of biotic interactions may overwhelm that of abiotic factors. Nutrient enrichment influenced community structure by changing the densities of bluegill Lepomis macrochirus and largemouth bass substantially but had a minor or no effect on other species. The management techniques used in these state‐operated lakes are usually targeted toward a particular species without adequately considering the other species within the community. Our results show that attention to community‐level interactions could provide valuable insight into factors that affect the quality of the fishery, insight that is not available through traditional population‐level assessments.

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

“…There was evidence for competition both within and among species, and density-dependent growth was observed for each of the sport fish species we examined. As was previously observed (Novinger and Dillard 1978;Gabelhouse 1984;Guy and Willis 1990;Olive et al 2005), largemouth bass predation was a strong force in structuring sunfish and crappie populations. Lakes with dense largemouth bass populations typically contained sunfish and crappie populations with desirable size structure and growth, but the largemouth bass were mostly small individuals owing to density-dependent growth (Reynolds and Babb 1978;Paukert and Willis 2004).…”

“…Sport fish demographics that could be associated with competition or predation were included as potential explanatory variables. For example, largemouth bass metrics (relative abundance and size structure) were included as explanatory variables for bluegill demographics because largemouth bass predation can structure bluegill populations (Guy and Willis 1990;Olive et al 2005;Schultz et al 2008). The intensity of largemouth bass predation is partially determined by their abundance and size.…”

“…The intensity of largemouth bass predation is partially determined by their abundance and size. Bluegill CPE was likewise included in largemouth bass demographic models because bluegills can be prey and competitors for largemouth bass (Guy and Willis 1990;Brenden and Murphy 2004;Aday et al 2005;Olive et al 2005).…”

“…Competition from and habitat alterations caused by invasive or introduced species, such as the common carp Cyprinus carpio and gizzard shad Dorosoma cepedianum, can result in suboptimal sport fish populations (Aday et al 2003;Michaletz and Bonneau 2005;Weber and Brown 2009;Jackson et al 2010). Lastly, predation by apex predators, such as largemouth bass, can strongly influence growth and size structure of bluegill and crappie populations (Gabelhouse 1984;Guy and Willis 1990;Olive et al 2005;Schultz et al 2008).…”

Fish communities in coastal freshwater ecosystems: the role of the physical and chemical setting

“…We hypothesized that a higher proportion of small-bodied than large-bodied fishes would occur in shallow embayments dominated by vegetated habitat [1]. In contrast, large embayments having deep, open habitat would provide support for large-bodied fishes [6], resulting in a low proportion of small-bodied fishes due to predation [10,27]. …”