The influence of submerged aquatic vegetation on trophic relationships of largemouth bass

Abstract

Aquatic vegetation is considered a nuisance in many lakes and reservoirs supporting largemouth bass populations, and control (eradication) of vegetation is often undertaken. Yet, the relationship between submerged aquatic vegetation and adult largemouth bass, from a trophic standpoint, is poorly understood. I attempted to quantify this relationship by comparing available prey with consumption from the perspective of individual largemouth bass and the largemouth bass population in Flat Top Lake, West Virginia in 1986 and 1987.

The abundance of largemouth bass ≥200 mm long was positively associated with vegetation density, although no relationship was apparent between the length and relative weight of adult largemouth bass and vegetation. Forage fish abundance was also positively related to vegetation density. Vegetation was heavily utilized by most fish species in the reservoir. Consumption (quantity and diet composition) of individual largemouth bass did not differ among the vegetation densities considered. However, the increased abundance of available prey associated with increased vegetation densities led to increased overall consumption by the largemouth bass population. Thus, largemouth bass production potential was positively related to vegetation density. Increases in the vegetation/open water interface had no short-term (one month). Evidence from this study indicates that aquatic vegetation could be managed to increase the productivity of largemouth bass in Flat Top Lake. The benefits to largemouth bass provided by aquatic vegetation in Flat Top Lake and similar systems should be considered prior to initiating vegetation control activities.