Cooperative Fish and Wildlife Research Units Program: Mississippi
Education, Research and Technical Assistance for Managing Our Natural Resources

Habitat associations of three black bass (Micropterus) species were examined in six habitat types (i.e., sediment, gravel, rock, riprap, brush, aquatic plants) along a cascade of ten reservoirs in the Tennessee River. We tested whether black bass habitat selection differed among species, and if species co-occurrence depended on habitat type. We found that some species occurred in some habitats in proportion to habitat availability, some at higher frequencies, some at frequencies lower than availability, and that juveniles and adults exhibited similar occurrence patterns. Our habitat selection results largely corroborate previous descriptions of black bass habitat associations and generally track preference for lithic habitats as reported in native streams. We expected black bass species to show negative co‐occurrence to avoid competitive interactions. Nevertheless, we found that with few exceptions, adults co-occurred in habitats mostly as expected by chance, and juveniles co-occurred more often than expected by chance. Our findings imply that environmental filtering, rather than competitive interactions that dominate in natural environments, may be the dominant mechanism shaping black bass assemblages in reservoirs of the Tennessee River. The observed patterns of habitat selection and co-occurrence further suggest that conservation and management of black bass assemblages in reservoirs can be supported through habitat management activities. Protecting and enhancing the remaining lithic habitat in the reservoirs as well as recovering habitat blanketed by sediment could provide desirable environments for all black bass species.