BLACK RIVER STUDIES JOHN L. FUNK EDWARD M. LOWRY MERCER H. PATRIARCHE Missouri Conservation Commission Fisheries Section ROBERT G. MARTIN Virginia Commission Game and Inland Fisheries and ROBERT S. CAMPBELL TIMOTHY R. O'CONNELL, JR. University of Missouri Wildlife Research Unit THE UNIVERSITY OF MISSOURI STUDIES Columbia, Missouri 1953 THE UNIVERSITY STUDIES COMMITTEE W. ALBERT BRENT, Chairman A. STEAL ARTLEY WILLIAM H. PEDEN HENRY E. BENT DAVID PINKNEY LOUIS G. KAHLE LOREN REID GEORGE B. PACE GEORGE H. VINEYARD RALPH H. PARKER FRED C. ROBINS, Secretary The chief function of the University of Missouri Studies is to publish the results of original research by members of the faculty and graduate students. It is devoted to the publication of extensive papers not included under the general and divisional bulletins. Papers of exceptional merit from sources other than the faculty and students of the University will, however, be considered for publication provided that they deal with a subject of particular interest to Missouri. Address all communications regarding the Studies to the Chairman, University Studies Committee, University of Missouri Columbia, Missouri Price $2.50 f; 0 ,-..."/ I-ri I.V L. 611161iiiitdi Vol. XXVI THE UNIVERSITY OF MISSOURI STUDIES No. 2 THE BLACK RIVER STUDIES JOHN L. FUNK EDWARD M. LOWRY MERCER H. PATRIARCHE Missouri Conservation Commission Fisheries Section ROBERT G. MARTIN Virginia Commission Game and Inland Fisheries and ROBERT S. CAMPBELL TIMOTHY R. O'CONNELL, JR. University of Missouri Wildlife Research Unit THE UNIVERSITY OF MISSOURI STUDIES Columbia, Missouri 1953 L. C. Card No. 53-13013 Copyright, 1953, by The Curators of the University of Missouri PRINTED IN THE UNITED STATES OF AMERICA TABLE OF CONTENTS Chapter Page Introduction 5 I The Black River Basin in Missouri 11 II The Benthos of Black River and Clearwater Lake, Missouri 25 III The Small Fishes of Black River and Clearwater Lake, Missouri 45 IV The Population of Larger Fishes in Black River, Missouri 69 V Age and Rate of Growth of Five Species of Fish in Black River, Missouri 85 VI Management and Utilization of the Fishery of Black River, Missouri 113 VII Appraisal of the Fishery of Black River, Missouri 125 Appendix 131 t INTRODUCTION In 1947 Black River, one of Missouri's principal Ozark streams, flowed uninterruptedly past the incomplete Clearwater Dam, a flood-control project begun in 1940 in the southeastern part of the state. A year later a seven- mile stretch was inundated by the 1,650 acre Clearwater Lake. The Black River Studies were initiated in 1947 as a pre-impoundment investigation of the limnology and the fishery of the river. Post-impoundment data, covering the years 1948 through 1950, were gathered from the flooded portion of this same section of river. The results pertaining to the small fishes and the bottom fauna are included also in these Studies. The remaining ob- servations on the lake will appear in future publications. The pre-impoundment phase was planned as a two-year study, but early closure of Clearwater Dam permitted only a three-month period of summer observations on the river at the middle stations, in which most emphasis was placed on the fishes and the bottom fauna. However, on the other sections of the river the studies of larger fishes were continued over a six-month period in both 1947 and 1948. Limnological observations were supporting in nature but incomplete. Work on Clearwater Lake was inten- sive from June through mid-September and was supported by early spring and late fall collections. Records of pre- and post-impoundment researches are so uncommon in the literature as to add unusual interest to this undertaking. No other detailed studies are known for the Midwest. To the best of the authors' knowledge this is the first study of the limnology and the fishery of a Missouri Ozark stream. The only other detailed report on Ozark waters is a description of the fish population of the Illinois River in Oklahoma to be summarized in one of the following sections. Pre- and post-impoundment observations of the same area may give sufficient information so that some prediction is possible as to what may be expected where other comparable Ozark streams are impounded. Early post-impoundment observations permit study of the dynamics of develop- ing populations. Other reasons for these studies included an interest in the biology of rivers characteristic of the Ozark Highland. Further, the investigation was in keeping with the statewide interest in the sport fishery of these small- mouth bass streams common to southern Missouri. This fishery represents a recreational resource for which the state is well known. The Missouri Conservation Commission and the people of the state have made a con- certed effort to preserve this resource from loss caused by extensive reservoir construction. These Studies and other investigations now in progress will furnish information pertinent to the management of this smallmouth bass fishery; will show specifically what changes occur in the fish population with impoundment; and will furnish some measures whereby the river resource and the lake resource which replaced it may be compared. Black River is characteristic of Ozark Highland streams and their fishery problems. In the headwaters, the water is clear and the volume of flow is maintained by springs. The river bed is broad, and within the chert fill, the river channel changes its course frequently. The rate of fall is approximately five feet per mile; long pools are connected by fast riffles. Downstream the Black River is deeper, more turbid, and with few riffles. This description is expanded in the first section of the Studies. The results of river studies showed that this smallmouth bass Ozark stream was much like trout streams. Similarities were evidenced in channel and flow characteristics, in kinds of bottom organisms, in the importance of game-fish species, and in the presence of a large population of suckers. When compared with trout streams the production of bottom fauna ranked about medium. Smallmouth bass and rock bass were the most important game species in the portion of the river to be inundated by the lake. Here the rough fishes included the longear sunfish, gizzard shad, hog sucker, and redhorse suckers. Downstream from the smallmouth bass habitat, whore the river was deeper and more turbid, the flathead catfish, carp, buffalo, bluegill, white crappie, and largemouth bass were more plentiful. In the river there was an unusually rich small-fish population of sixty-eight species. Twenty of these species were minnows. Sunfishes and suckers were also numerous. There were two major observations relative to the dynamics of population development of small fishes in the lake. The year in which a species first became abundant appeared to be a function of the time lapse between hatching of the first spawn in the lake and maturity. Thus minnows with a life span of one year became abundant in 1948, whereas white crappie, which mature during their third growing season, did not be- come abundant until 1950. Secondly, small-fish populations varied from year to year due to variable spawning success. Factors which affected spawning success included size of brood stock, age of maturity, and water-level fluctuations during spawning. Development of bottom fauna was rapid: in three months the benthos was as abundant as it was three years later. A comparison of the river and lake studies on small fishes and bottom fauna showed the pre- and post-impoundment populations to differ in two important respects. One, the variety of organisms was markedly reduced in the impoundment; and, two, most of the dominant species in the lake were different from the species which were dominant in the river. With reference to the prediction of the fish population in a future reservoir in this Ozark Highland area, these data would suggest that the species be- longing to the backwater areas in the river (in this instance gizzard shad, white crappie, largemouth bass, and golden shiner) would be among the dominant fishes in the lake. In general the more important river fishes would not be important numerically in the lake. The time of appearance of each of these species in numbers in the lake is somewhat predictable. The abundance of benthos per unit of area in a new Ozark reservoir is not likely to be greater than that in the stream that preceded it. Specific management techniques employed on the Black River water- shed included stocking and regulation of the fishery. The stocking appeared to have followed no definite plan and probably had little beneficial effect. Regulations apparently were well conceived and progressive. Rate-of-growth studies and a measure of the harvest through a creel census provide some ba- sis for judging the effectiveness of management. The growth rate of small- mouth bass was found to be about average for the state. Rock bass, green sunfish, and longear sunfish were considered to be slow growing. The creel census showed a rate of catch of about 0.4 fish per hour which was some- what lower than the statewide average. Suckers, smallmouth bass, and rock bass were most abundant in the catch. Rough fish were harvested chiefly by gigging and snaring. The findings of this research project are here presented in seven separate but related sections. The first section, "The Black River Basin in Missouri," furnishes background common to the remaining sections. The last article, "Appraisal of the Fishery of Black River, Missouri" relates the information appearing in the previous sections and emphasizes the outstanding biological features of the river and the successional changes within the impoundment. Descriptions of field stations and of methods are given in the appendix.