SREL Reprint #2487

An exploration of factors influencing lotic insect species richness

Neal J. Voelz1 and J. Vaun McArthur2

1Department of Biological Sciences/MS 262, St. Cloud State University, St. Cloud, Minnesota 56301, USA
2Savannah River Ecology Laboratory, University of Georgia, Drawer E, Aiken, South Carolina 29802, USA

Abstract: An understanding of factors that influence species richness of lotic insects is generally lacking. We present comparative data on aquatic insect species richness from several North American and other streams. Factors Such as large sample numbers and drainage area (species area relationships) are not significant predictors of species richness across the streams we examined. We explore several hypotheses regarding the origins and maintenance of species richness using Upper Three Runs Creek (UTR), South Carolina, USA, as a reference stream. UTR has the highest species richness of any stream in the Western Hemisphere. Hypotheses examined included historical, regional and local processes such as: (1) Evolutionary time, (2) disturbance regime/environimental variability, (3) temperature/evolutionary-speed, (4) productivity, and (5) habitat heterogeneity. Of these hypotheses, we suggest that productivity and habitat heterogeneity appear to contribute most to the high species richness found in UTR. We believe that multi-disciplinary analysis of other streams is necessary because without this crucial information our knowledge of, and desire to protect biodiversity in streams will be wanting.

Keywords: aquatic insects, biodiversity, blackwater stream, habitat diversity, productivity, species richness

SREL Reprint #2487

Voelz, N. J., and J. V. McArthur. 2000. An exploration of factors influencing lotic insect species richness. Biodiversity and Conservation 9:1543-1570.

This information was provided by the University of Georgia's Savannah River Ecology Laboratory (srel.uga.edu).