Bulletin 81 / Minimum Oxygen Levels Survived by Stream Invertebrates Eugene W. Surber William E. Bessey Bulletin 81 December 1974 Minimum Oxygen Levels Survived by Stream Invertebrates Eugene W. Surber Former Research Biologist Virginia Commission of Game and Inland Fisheries and William E. Bessey Robert A. Taft Sanitary Engineering Center Cincinnati, Ohio VPl -WRRC-BULL 81 A publication of Virginia Water Resources Research Center Virginia Polytechnic Institute and State University Blacksburg, Virginia 24061 -r1) "'~DI V-5 ? . > •. ~)I PREFAC.E In the late spring of 1974 I received two lengthy letters from Gene Surber concerning research he had carried out many years ago but reported for the first time in this Bulletin. Gene was clearly concerned about the fate of this sizable effort, a concern heightened by the fact that he was much weakened by cancer. I felt it was important to ease Gene's mind by immediate publication of the manuscript without either editing or review. Dean Randal M. Robertson of the Research Division, Virginia Polytechnic Institute and State University, agreed after being apprised of the situation. Gene had contemplated some revision of the manuscript and it was in the hands of William T. (Bill) Mason, Jr., Interstate Commission on the Potomac River Basin, when Gene's letters arrived. We felt that the appropriate course of action was immediate publication via the Virginia Water Resources Research Center's Bulletin series. Bill's supportive actions and counsel were exceedingly helpful. In May of 1974, Gene and I discussed the-manuscript on the telephone. Although his voice was weak and the short conversation clearly tiring, his enthusiasm for and interest in this research were awe-inspiring. Except for the conversion of some figures into a form suitable for publication and for this preface, the manuscript has not been altered. Although I firmly believe in peer review, there are situations where human values should transcend the academic process-and for this I take full responsibility. My thanks to Dr. Kenneth L. Dickson and Anthony F. Maciorowski for helping with the preparation of the figures for publication. John Cairns, Jr. University Professor of Zoology and Director, Center for Environmental Studies Virginia Polytechnic Institute and State University iii TABLE OF CONTENTS Objective and Procedure Results 7 Conclusions and Discussion 17 Acknowledgments 19 Literature Cited 20 Figures 21 Tables 39 v LIST OF FIGURES 1. Water bath and glass insect tubes lifted from bath; Insect cells (5) at right . 23 2. Diagram of apparatus used for determination of minimum oxygen levels tolerated by stream invertebrates . 24 3. Initial head box, cooling unit (upper left), and Mount Oegasser 25 4. Mount Oegasser 26 5. Fluctuations in oxygen levels in the control and experimental tubes during a 76-hour test (Experiment 8) with four specimens of Orconectes rusticus. Vertical columns show points at which deaths of the individuals occurred in the experimental tube. All control specimens survived. 27 6. Fluctuations in oxygen levels in the control and experimental tubes during a 66-hour test (Experiment 2) with three specimens of Lirceus fontinalis 28 7. Fluctuations in oxygen levels in the control and experimental tubes during an 89-hour test (Experiment 20) with four specimens of Lirceus fontinalis 29 8. Fluctuations in oxygen levels in the control and experimental tubes during a 66-hour test (Experiment 3) with three specimens of Stenonema tripunctatum . 30 9. Fluctuations in oxygen levels in the control and experimental tubes during a 69-hour test (Experiment 14) with four specimens of Stenonema heterotarsale 31 10. Fluctuations in oxygen levels in the control and experimental tubes during an 89-hour test (Experiment 20) with four specimens of Stenonema ares 32 11. Fluctuations in oxygen levels in the control and experimental tubes during a 70-hour test (Experiment 7) with three specimens of lsonychia bicolor 33 vi 12. Fluctuations in oxygen levels in the control and experimental tubes during a 91-hour test (Experiment 17) with three specimens of Ephoron leukon 34 13. Fluctuations in oxygen levels in the control and experimental tubes during a 77-hour test (Experiment 8) with two specimens of Acroneuria lycorias 35 14. Fluctuations in oxygen levels in the control and experimental tubes during an 87-hour test (Experiment 16) with four specimens of Psephenus herricki 36 15. Fluctuations in oxygen levels in the control and experimental tubes during a 92-hour test (Experiment 15) with one specimen of Corydalus cornutus 37 vii LIST OF TABLES 1. Number of Experimental Animals Used per Cell in Control and Experimental Cells 41 2. Dissolved Oxygen, Experiment 20 45 3. Summary of Dissolved Oxygen Experiments, Physical and Chemical Data . 46 4. Summary of Results of Oxygen Bioassays 48 5. Minimum Dissolved Oxygen Levels Survived for 12 Hours by Stream Invertebrates 52 viii OBJECTIVE AND PROCEDURE The objective of this study was to explore, experimentally, the lowest levels of oxygen that could be tolerated by some of the common invertebrate animals of streams in the Cincinnati area. Most of the bottom animals used in the experiments were collected from riffles of the Little Miami River above Milford, Ohio; the East Fork of the Little Miami above Batavia; the Mad River above Urbana, Ohio; and Mt. Carmel Creek near Mt. Carmel, Ohio. The experiments were carried out in a constant temperature bioassay room of the Aquatic Biology Section, Basic and Applied Sciences Branch, Division of Water Supply and Pollution Control, Robert A. Taft Sanitary Engineering Center, Cincinnati, Ohio. Apparatus Two oblong glass tubes were used (Figure 1), each 46.5 centimeters long and 41 millimeters in diameter, with 6 mm bore inlet and outlet stopcocks for regulating the flow-through rate, two 6 mm bore stopcocks for removal of samples (one unneeded), and a 26 mm vertical tube in the top side for diverting the flow temporarily while air bubbles were removed from the apparatus. In normal operation this latter tube was kept closed with a No. 6 rubber stopper, but during the removal of air bubbles, it served as an overflow. The vertical tube was originally designed for the insertion of an oxygen analyzer or an electric stirrer that could aid in the circulation of the water at low flow-through rates, but in these experiments which were run with a flow-through rate of about 600 milliliters per minute, it was found more practical to use the vertical tube for an overflow during insertion of the five insect cells and for removal of air bubbles. The experimental animals, usually two to four of each species, were placed within each of five clear plexiglass cells that were 51 mm long and 25 mm in diameter (O.D.). Each of the cells had removable plexiglass screw caps at one end while the other end was permanently closed. Short threaded stainless steel rods, 1/8 inch in diameter, were used to joint the five cells together in tandem. A longer stainless steel rod, 115 mm long, extended from the first eel I in the series through a No. 8 rubber stopper which closed the 41 mm opening in the Pyrex glass tube through which all animals were introduced simultaneously at the beginning of a test period. This stopper also served to hold the cells in a straight line within the tube. Each cylindrical plexiglass cell was perforated with 1 /16-inch holes throughout, including both ends, with as many as two dozen perforations to permit adequate circulation of water. Each of the experimental glass tubes was submersed in a compartment of a stainless steel water bath receiving the same cooling water. The cooling water was pumped with a No. 210 Gorman-Rupp centrifugal electric pump with rubber housing and impellers from a 55-gallon polyethylene tank into the stainless steel tank where it flowed through the two compartments, one containing . the control tube and the other t he experimental, before returning by gravity to the polyethylene tank. A "Blue-M" portable water cooler with thermostat was used to keep the water temperature constant in the water bath system. This arrangement is illustrated in Figure 2. The glass tubes were held in place in the compartments by means of an adj_ustable horizontal aluminum frame with two arms which could be raised and lowered vertically or tilted to any desired position. A tilted position was used at the beginning of a test period when bubbles were being freed from the apparatus via the vertical t ube or opening through which the test cells were inserted. Water Supply Regimen for the Experimental Tubes After reducing the pressure by passing through a pressure reduction valve, Cincinnati city water was passed through an activated carbon filter into a stainless steel headbox as illustrated in Figures 2 and 3. Here the temperature was controlled so that a temperature generally not exceeding 22°C was maintained in the control and experimental tubes. To accomplish this, the headbox was provided with a 1900-watt Chromalux heating element connected to a LaPine Electronic Relay, to which t he headbox thermoregulator was also connected. A small cooling uni t, with stainless steel coils (made in the Air-Conditioning Section of the Robert A. Taft Sanitary Engineering Center) and equipped with a two-stage bulb thermostat (temperature range 10° to 90° F.), was also installed in the headbox for cooling the water when needed. Polyvinyl chloride (PVC) pipe and vinyl tubi ng were used to convey incoming water. into the Mount Degasser (Figure 4), the basic principles of which were described by Mount ( 1961, 1964). The degassing chamber in this apparatus was a 42-gallon pneumatic, galvanized tank (20 by 36 inches) with its interior coated with polyester resin to prevent corrosion and possible contamination by zinc from the galvanized surface.