Aquatic Macroinvertebrates 



of the 



Upper French Broad River Basin 



David L. Penrose, David R. Lenat and K. W. Eagleson 



North Carolina Department of Natural Resources 



and Community Development, 

 P. O. Box 27687, Raleigh, North Carolina 27611 



ABSTRACT. — The aquatic macroinvertebrates of the Upper French 

 Broad River were sampled over a two-year period beginning in May 

 1977. The information gathered in this study, along with additional 

 data for other select tributary streams, were combined to generate a 

 list of 267 invertebrate taxa. The faunas of the French Broad River 

 and tributaries are compared to those of other rivers and streams of 

 the southern Appalachians to define "normal" faunal characteristics of 

 lotic systems in this geographic area. Information is presented on taxa 

 richness and abundance for the six major taxonomic groups. Temporal 

 and spatial changes in the benthic macroinvertebrate communities 

 were associated with changes in flow rates, watershed sizes, average 

 temperatures, canopies, substrate characteristics, and gradients. 



INTRODUCTION 



A chronicle of the French Broad River by Dykeman (1955) referred 

 to the river as "the classic example of an Appalachian River". Dykeman 

 presented the French Broad as a study of paradoxes: allure and despair, 

 problems and promises. These paradoxes are especially evident today as 

 we consider the inevitable growth and development of the upper French 

 Broad River basin in North Carolina, balanced against the assimilative 

 capacity of the river. Can the river continue to absorb perturbations and 

 remain a valuable natural resource? 



Water quality records for the French Broad River in Transylvania 

 County are of little help in answering this question. A water quality 

 monitoring site is located in Rosman, North Carolina, and is main- 

 tained by the Division of Environmental Management. The water qual- 

 ity is described as very good, with few stream contraventions recorded 

 (N.C. Department of Natural Resources and Community Development 

 1976). This site is also monitored by the United States Geological Sur- 

 vey, and continuous stream flow records have been collected since 1955. 

 The average stream discharge at Rosman, located just below the conflu- 

 ence of the North and West Forks, is 242 cfs (6.85 m 3 /sec) and the 

 average rainfall there is 122.9 cm/ year (United States Geological Survey 

 1979). Average flow of the river during the period of the study herein 

 reported can be seen in Figure 1. The watershed above Rosman is 



Brimleyana No. 8:27-50. December 1982 27 



