Relations among Habitat and Population Characteristics of Spotted Bass in Kansas Streams

Abstract

Spotted bass Micropterus punctulatus are popular sport fish in streams and reservoirs throughout the southeastern United States. Despite their popularity, there is a paucity of information on population characteristics and habitat requirements of spotted bass in streams. The purpose of this study was to document the factors that influence spotted bass populations in Kansas streams. Study sites were selected throughout the native range of spotted bass in Kansas. Spotted bass were sampled by electrofishing, and 31 habitat variables were measured at 16 study sites. Linear regression analyses (single and multiple) were used to determine relationships between habitat variables and spotted bass density (number/ha), biomass (kg/ha), catch per effort (CPE; number per minute of electrofishing), relative weight (W_r ), and growth. Variability in density of spotted bass 180 mm or longer was best explained by rootwad area (m²/ha). However, variability in biomass and CPE of spotted bass 180 mm or longer was best explained by rootwads and undercut bank area (m²/ha). Relative weight was negatively correlated with density and CPE. Mean back-calculated length at age 3 was positively correlated with W_r. These data indicate that habitat, such as woody debris and undercut banks, influences spotted bass density and biomass in Kansas streams.