Largemouth Bass Nest Site Selection in Small, North Temperate Lakes Varying in Littoral Coarse Woody Habitat Abundances

Abstract

Coarse woody habitat (CWH) in the littoral zone is an important habitat feature in freshwater systems and has been suggested to influence nest density and nest site selection by black basses Micropterus spp. (e.g., largemouth bass M. salmoides and smallmouth bass M. dolomieu). To test for a relationship between nest site selection or nest density and the abundance of littoral CWH, we monitored largemouth bass nest site selection in the littoral zones of two small, northern Wisconsin lakes (comprising a total of three separated basins) for three consecutive spawning seasons. Our study sites varied in natural and manipulated abundances of CWH; spawning seasons before and after a whole-basin CWH reduction or a whole-basin CWH addition were examined. Within-basin analysis provided some evidence that local variation in CWH abundance influenced local nest density; however, this relationship was only significant for one basin in a single season. Among basins and across seasons, we observed a positive but nonsignificant effect of littoral CWH density on nest density and inconsistent responses to the CWH manipulations. Although littoral CWH is an important habitat feature influencing fish populations, communities, and life histories, our results suggest that CWH did not directly limit largemouth bass nest densities and was not a strong driver of nest site selection in these lakes. Nevertheless, policies allowing human-mediated removals of CWH from freshwater systems may still be detrimental to fish communities and other taxa that are dependent upon CWH.

Received March 31, 2011; accepted July 13, 2011

ACKNOWLEDGMENTS

We thank Andrew Jones, Derek West, and two anonymous reviewers for helpful comments that greatly improved this manuscript. We are grateful to everyone who assisted with fieldwork, especially Jeff Biermann, Bri Kaiser, Adam Kautza, Anna Engfer, Michelle Nault, and Steve Reinhardt. Scott Van Egeren and Michelle Woodford deserve special thanks for conducting the annual littoral CWH surveys. Funding was provided by a National Science Foundation Biocomplexity in the Environment grant to Steve Carpenter, University of Wisconsin–Madison (DEB-0083545), a National Science Foundation Research Experiences for Undergraduates fellowship to J.J.W., and a summer fellowship from the Tug Juday family. Housing and additional financial support were provided by the Center for Limnology and Trout Lake Station, University of Wisconsin–Madison.