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COFFEEVILLE LAKE WARRIOR - TOMBIGBEE RIVERS, ALABAMA DESIGN MEMORANDUM THE MASTER PLAN APPENDIX D - FISH MANAGEMENT PLAN A publication prepared under terms of a contract research project between the Corps of Engineers, Mobile District and the Agricultural Experiment Station of Auburn University, Auburn, Alabama. The departments of Agricultural Economics and Rural Sociology and Fisheries and Allied Aquacultures were responsible for the research and development of this report. Auburn University staff members with major responsibilities for the research and development of this report were David R. Bayne, Carolyn Carr, Wm. Dumas III, J. D. Grogan, John M. Lawrence, David Rouse, Karen Snowden, Glenn Stanford, David Thrasher, Charles J. Turner, and J. Homer Blackstone as project leader • . ,-1 , U. S. ARMY ENGINEER DISTRICT, MOBILE CORPS OF ENGINEERS MOBILE, ALABAMA July 1974 TABLE OF CONTENTS Text Table 1. 2. Page Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 A. Purpose. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 B. Master plan . . .. . .. 1 C. Fish management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 D. Classification of the fishery. . . . . . . . . . . . . . . . . . . . . . . . • . . . . . . . . . . . 1 Physical Characteristics of the Aquatic Habitat that Influence Fish Production and Harvest. . . . . . . . . . . . • . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 A. General.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 B. Drainage area . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 1. Topography. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 2. Area 4 3. Land usage. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 4. Rainfall patterns. . . . . . . . . • . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 5. Runoff rates. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 6. stream regulation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Impoundment................. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . • . 13 1. Morphometry. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 2. Altitude . . .. .. 14 3. Area.... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 4. Mean depth. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 C. , .. . , " . . 3. 5. Maximum depth. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 14 6. Productive-depth zone ........•.........•...............•... 14 7. Volumes of euphotic strata. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 15 8. Length of the shoreline. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 15 9. Eulittoral zone. .. 15 10. Inflow... .. . .. .. . .. .. .. 16 11. Outflow. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 16 12. Retention time 13. Internal flow currents. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 16 14. Penstock depth. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 15. Water-level fluctuations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 17 16. Uncleared flooded areas. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 18 17. Meteorological influences 16 17 18 Water Quality in Relation to Fish Production. .. . . . .. . .. . . . .. .. . .. 19 A. General 19 B. Water quality constituents 19 1. 2. 3. Temperature. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 19 a. Temperature stratification in a lake. . . . . . . . . . . . . . . . . . . . .. 20 b. Temperature conditions in tailwaters 21 Dissolved oxygen .•......................................... 21 a. Dissolved oxygen stratification in lake 23 b. Dissolved oxygen conditions in tailwaters . .. .. . . . .. . .. . . . .. 24 pH.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 24 ii 4. Carbon dioxide and alkalinity 26 5. Chemical type. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 6. Plant nutrients 29 a. Nutrient enrichment in impolmdments . . . . . . . . . . . . . . . . . . 29 b. Macro-nutrients. . . . . . . . . . . . . . . . . . . . • . . . . . . . . . . . . . . . . 31 c. Micro-nutrients ..... '" . ..... . . . .. ... ... . . .. . ..... . . 31 d. Nutrient sources. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 7. 8. C. 4. Toxic substances 35 a. Pesticides. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36 b. Heavy metals. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40 c. Industrial toxicants. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40 Sediment load •......................................... " Pollution sources. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Aquatic Plants in the Impolmdment. .. .. .. . 42 43 50 A. Aquatic plant - definition 50 B. Factors affecting aquatic plant growth 50 C. Aquatic plant groups and associated habitat problems.. . . .. .. . ... 51 1. Bacteria. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 52 2. Fungi. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52 3. Algae................................................... 52 4. Flowering plants. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56 Aquatic plant populations of Coffeeville Lake and methods for their control ............................•................... 58 D. iii 5. Description of the Fishery A. Warmwater species of fish in Coffeeville Lake. . . . . . . . . . . . . . . . . • . •. 60 B. Coldwater species of fish in Coffeeville Lake ..•..................• 67 C. The downstream species from Coffeeville Dam ..................•. 68 D. Rare and endangered species ..............•...................... 68 E. Fish-food organisms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 68 F. History of parasite and disease incidents in fish populations . . . . . . . .. 70 G. History of fish kills .................•........................... 71 H. Establishment of Coffeeville Lake fishery including flooding schedule. 81 I. History of species composition, relative ablUldance, and condition within each species including methods used to obtain fish samp·les . • .. 82 1. 6. 60 Methods of sampling fish populations ................•.•..... 0 82 a. Rotenone sampling ...........................•.......... 83 b. E lectrofishing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 85 2. Fish population studies (Rotenone) 3. Fish population studies (Electrofishing) 1973-1974 •....•.•.•.. 91 4. Comparisons of relative conditions (KnJ 86 91 J. Fishing pressure 99 K. Creel census data 99 Management of the Fishery ........................................•. 101 A. Reservoir fishery biology ...............•...................•.... 101 1. Factors affecting fish reproduction 102 a. 103 Adequacy of spawning area iv b. Water fluctuation 103 c. Water temperature .......•................................ 103 d. Silt-laden waters 103 e. Repressive factor 105 f. Size of brood fish .......................................• 105 g. Food availability during period of egg-formation ............• 105 h. Crowding 106 i. Egg-eating habit j. k. 2. Reproductive success of prey upon which predators feed after reaching fingerling stage 106 strength of predation upon yOlmg predator species 106 Predator - prey relationships I 7. ........................................• 106 I 107 B. ResLUne of factors affecting fish production in reservoirs 1] 3 C. 116 Information vs. action 1. Public relations ............................................• 117 2. Fishing access 118 3. Fishing intensity 119 4. Creel limits ......................................•........•. 119 5. Evaluation of fishery management changes ....................•. 120 6. Fishing tournaments and rodeos Coordination with Other Agencies A. Personnel and funding B. Cost - benefit projections •.............................. 120 123 .........................................••• 123 124 v C. Equipment for bio logist ........•....•..•.•..••...•...•••••••..••. 125 D. Job description - Fisheries Management Biologist ........•.....•..• 126 E. Budget ................................•.•......••.•....•...••.• 128 8. Research Needs for River and Impoundment Management ......••.•••..•. 129 9. Synopsis ..................................•........................ vi 133 TABLES Table Page 1. Average monthly and annual precipitation for Coffeeville Lake. 6 2. Average concentrations of macro-nutrients (elements) in filtered water, suspended matter, bottom soils, rooted plants, and fish from Coffeeville Lake. 32 3. Average concentrations of micro-nutrients (elements) in filtered water, suspended matter, bottom soils, rooted plants, and fish from Coffeeville Lake. 34 4. Average concentrations of pesticide residues in fish collected from Coffeeville Lake, 1971. 37 5. Average concentrations (ppm wet weight) of pesticide residues in various species of fish collected from the Tombigbee River compared with the overall average from species collected in all rivers in Alabama, 1971. 38 6. Average concentrations (ppm wet weight) of pesticide residues in various species of fish collected from public fishing lakes located in the Coffeeville Lake drainage area, compared with averages in species from all 23 public fishing lakes in Alabama, 1971. 39 7. Average concentrations of heavy metal elements in filtered water, suspended matter, bottom soil, rooted plants, and fish from Coffeeville Lake. 41 8. Black Warrior River waste sources. 44-47 9. Upper Tombigbee River waste sources. 48 10. Lower Tombigbee waste sources. 49 11. List of phytoplankton genera collected from Coffeeville Lake in 1963. 55 12. List of potentially noxious flowering aquatic plants in Coffeeville Lake in 1973. 59 13. A check list of warmwater fish species believed to be present in Coffeeville Lake, separated into Game, Commercial, and Other groupings. 61-66 vii TABLE S, cont'd Table 14. Macroinvertebrates from weed samples taken from Coffeeville Lake. 69 15. Fish parasites in the Mobile River basin. 72-78 16. Viral, bacterial and ftmgal diseases of reservoir fish. 79-80 17. Fish population data collected by rotenone sampling in Coffeeville Lake in 1955-1957. 87-88 Lengths (in inches) used to classify fish of different species as young, intermediate, or harvestable, and as forage, carnivorous or other. 92-93 Results of electrofishing at selected sites on Coffeeville Lake, 1974. 94 Results of electrofishing at selected sites on the Tombigbee River below Coffeeville Dam. 95 18. 19. 20. 21. 22. Reproductive characteristics of various species of fresh-water fish. 104 Maximum sizes of forage fishes largemouth bass of a given inchgroup can swallow. 109 viii FIGURES Title Page 1. Black Warrior - Tombigbee drainage area. 9 2. Tennessee - Tombigbee Waterway. 10 3. Oxygen content of water and its relation to fish. 22 4. Relationship of pH of reservoir waters to their suitability for fish prod uction. 25 5. Relationship and determination of CO2 , HC0 ' C0 --, and 3 3 OH- in natural waters. 27 6. Distribution of ~ factor for various sizes of three groups of fish collected from Coffeeville Lake in 1974. 96 7. Distribution of Kn factor for various sizes of three groups of fish collected from the Tombigbee River at Jackson, Alabama in 1974. 97 Fish Management Plan for Coffeeville Lake 1. Introduction. I-A. Purpose. This report on the fishery management of Coffeeville Lake presents a plan to preserve all species of fish within the impoundment, to increase the production of harvestable-sized fish through the improvement of the aquatic habitat, and to provide the most favorable lake conditions for public fishing. I-B. Master plan. The fish management plan will be a part of the approved Master Plan for the continued development and management of Coffeeville Lake. I-C. Fish management. Fish management (Appendix D) will be in accordance with ER 1130-2-400, APP.A (May, 1971); ER 1120-2-400; ER 1120-2-401; AR420-74; Fish and Wildlife Coordination Act of 1958 (PL 85-624) as amended; and Federal Water Projects Recreation Act of 1965 (PL 89-72). I-D. Classification of the fisherv. The fishes in Coffeeville Lake have been classified as warm-water sport, commercial, and miscellaneous species. They are to be managed to provide the public with the maximum sustained yield of harvestably sizes of sport and commercial species and to insure the continued existence of the miscellaneous species. 2. Physical Characteristics of the Aquatic Habitat that Influence Fish Production and Harvest. 2-A. General. Aquatic habitats are as numerous as the waters themselves. Rising in mountains, hills, or plains, small streams meander through the countryside uniting with one another to form larger streams and eventually a river. Each change in the size and shape of a stream forms a new habitat with a new set of environmental conditions and a different assemblage of aquatic organisms. These new conditions, however, are never independent of upstream influence. The same is true of man-made impoundments on rivers. Morphometric features of the im- poundment basically determine the types of aquatic habitats, but environmental conditions in the lake will largely depend on the quality and quantity of the collective waters from the drainage area. The physical features of Coffeeville Lake and its associated drainage area are presented in this section of the report. 2-B. Drainage area. 2-B-1. Topography. The Black Warrior River rises in the Cumberland Plateau (a subdivision of the larger Appalachian Plateau Physiographic Province) in northcentral Alabama. This is a submaturely eroded upland area developed on the sandstones, shades, and coal beds of the Pottsville Formation. approach 1500 feet msl. of this region. Elevations The three forks of the Warrior drain the major portion The western-most fork, the Sipsey, flows out of the central part of the plateau and joins the middle fork, the Mulberry, in eastern Walker County, Alabama. They combine with the Locust Fork which drains the eastern edge of the 2 Cumberland Plateau and the southwestern tip of the Ridge and Valley Province, to form the Black Warrior River at river mile 393.6. From here the Black Warrior flows in a southeasterly direction towards Tuscaloosa, Alabama. The average elevation of the hills in this part of the plateau is about 500 feet msl. The Fall Line on the Warrior is at Tuscaloosa where the river leaves the Cumberland Plateau and enters the Coastal Plains Physiographic Province. The uppermost subdivision of this province, the Central Pine Belt (Fall Line Hills), is a region of low sandy hills. After leaving the Central Pine Belt the river flows into the Black Prairie Belt. The Black Prairie Belt is developed on the Selma Chalk, which forms a dark fertile calcareous clay that is the characteristic soil type of this ag-ricultural region. Local relief is low and drainage is generally poor. The Black Warrior empties into the Tombigbee River near the lower edge of the Black Prairie Belt at Demopolis, Alabama. The Tombigbee River is formed in the northeastern corner of Mississippi. Except for isolated portions of the eastern edge all of the drainage basin lies within the Coastal Plains Province. The Central Pine Belt occupies most of the eastern part of the basin and the Black Prairie Belt occupies most of the western part. Their common border marks the general course of the Tombigbee River in Mississippi. The physiography of these hvo subdivisions is similar in both the Tombigbee and Warrior drainages. The Central Pine Belt is an upland area with steep hills and sandy soil while the Black Prairie Belt is a poorly-drained area with gently rolling hills and calcareous soil. In the Black Prairie Belt elevations range from nearly 500 feet msl in the north to about 150 feet msl in the south. 3 Near the Alabama-Mississippi state line the river enters the Black Prairie Belt and flows through it towards Demopolis, where the Tombigbee is joined by the Black Warrior. Demopolis Lock and Dam is located 2.5 miles west of Demopolis near the lower edge of the Black Prairie Belt. Below Demopolis Lock and Dam the river flows southward through the southern edge of the Black Prairie Belt, through the Chunnennugge Hills Region, through the Southern Red Hills Region to its southern border which is the location of the Coffeeville Lock and Dam. This is a distance of approximately 96.5 river miles. In this reach of the Tombigbee River the elevation of surrounding ten"aine ranges from 200 to 100 feet msl. 2-B-2. Area. The total drainage area above Coffeeville Lock and Dam is approximately 19,000 square miles. Roughly 19 percent of tllis area (about 3,600 square miles) is between Demopolis and Coffeeville Locks and Dams. 2-B-3. Land usage. Prior to World War II much of the Black Warrior drainage area supported a rural population that engaged in moderate row-crop farming. Much of this farming took place on unterraced, marginal, hilly lands. Tllis caused e),."tensive sheet and gully erosion in the upper reaches, and resulted in an annual sediment load as great as 200 tons per square mile. During and following World War II the rural population declined. The usage of the land changed from primarily farmlands to forestry and surface mining. As much as 60 percent of the Warrior watershed above Tuscaloosa is considered as potential strip mining sites. By 1970 the usage of the upper portions of the Warrior water4 shed were about 50 percent forest and 30 percent crop and pasture lands. The re- maining 20 percent of the land area was occupied by residential, business, industrial (including surface mining), and transportation facilities. In the reach of stream between Oliver and Warrior Dams, more e.,:tensive rowcrop farming occurs than in the areas upstream from Oliver. On the Tombigbee arm, the same trends in land usage has occurred during the last 50 years. Currently land usage would be about 50 percent forest, 35 percent in crop and pastm'e lands, and 15 percent in residential, business, industrial, and transportation facilities. sediment loading on the Upper Tombigbee is moderate when compared with that on the Black Warrior arm. On the Lower Tombigbee between Demopolis Lock and Dam and Coffeeville Lock and Dam there is a mixture of land usages, Forest lands account for about 60 percent, pasture, and row-crop lands about 30 percent, and residential, business, industrial, and transportation facilities about 10 percent. 2-B-4. Rainfall patterns. The drainage basin above the study area lies in a region of fairly heavy annual rainfall. There is some seasonal variation, with about 41 percent of the rainfall coming during the wet season (December through April) and only about 18 percent coming during the dry season (September through November). The average annual rainfall is about 57 inches (Table 1). The highest recorded annual rainfall is 87.02 inches at Booneville, Mississippi, in 1932. The lowest recorded annual rainfall was 27.95 inches at Demopolis Lock and Dam in 1954. Most of the flood-producing storms that occur over the drainage basin are of the frontal type. These storms usually occur in winter and early spring. 5 Major Table 1. Average monthly and annual precipitation for Coffeeville Lake. Month Rainfall, inches January 4.70 February 5.14 March 6.78 April 5.71 May 4.36 June 3.94 July 6.60 August 4.42 September 3.70 October 2.54 November 3.65 December 5.24 --- Annuai average 56.79 Information from station at Thomasville, Alabama. 6 floods are occasionally produced in the summer by the inland passage of a hurricane. Localized flooding of tributaries may occur during the summer as a result of convectional storms. 2-B-5. Runoff rates. The source of water entering Coffeeville Lake is the combined flow from the Tombigbee and Black Warrior Rivers. Although these two drainage basins are adjacent to one another their geology is totally different. About 75 percent of the Black Warrior basin is in the CUmberland Plateau. This is a steep, hilly region in which the bedrock lies generally close to the surface. A large percentage of the precipitation enters a stream unusually quickly, with relatively little water being stored as gTolmd-water. TIJis results in extreme seasonal variations in the discharge of the river. stream -flow patterns are also affected by the extensive development of the Black Warrior above Demopolis. Although these developments tend to moderate seasonal changes of stream discharge, short-term discharge variations are often extreme. The Tombigbee Basin is located in the Coastal Plains. In this region a fairly thick layer of soil is underlain by sedimentary bedrock. Local relief is moderate. In this situation more of the precipitation is stored as ground-water than would be in a rocky, upland area (such as the Warrior Basin). Because its grolmd-water reservoir is larger, the rate of flow of the Tombigbee River is more stable than that of the Black Warrior River. At the present time there is no significant development of the Tombigbee above Demopolis; therefore the flow of the river is regulated by the meteorological conditions upstream. 7 The maximum recorded discharge of the Tombigbee River at Gainesville (just above Demopolis Reservoir) is 168,000 cfs on January 11, 1949. The mini- mum recorded discharge at this point is 250 cfs on September 21 and 22, 1954. The average discharge is 11,530 cfs and the average annual runoff is 18 inches. The maximum recorded discharge of the Black Warrior River at Oliver Dam (91 miles above Demopolis Reservoir) is 224,000 cfs on February 21, 1961. The minimlUll recorded discharge is 37 cfs on October 23, 1953. The average discharge is 7,505 cfs and the average annual rLilloff is 21.1 inches. The difference between these figures and the corresponding figures of the Gainesville site reflects the aforementioned differences in the geology of the two watersheds. At Demopolis Lock and Dam the average discharge is 21,780 cfs. * The maxi- mum and minimum recorded discharges are 250,000 cfs on February 28, 1961, and 50 cfs on August 1-6, 1954, respectively. The estimated 10-year 7-day low flow is 750 cfs. At Coffeeville Lock and Dam the average discharge is approximately 26,000 cfs. The maximum and minimum recorded discharges are 153,000 cfs on March 7, 1971 and 957 cfs on June 18, 1968. The estimated 10-year 7-day low flow is 1,100 cfs. 2-B-6. stream regulation. The Black Warrior - Tombigbee drainage area and stream profiles are shown in Fig'ures 1 and 2. The uppermost headwaters of the Black Warrior River are the Sipsey, Locust, and Mulberry Forks. Alabama Power Company impOlillded Sipsey Fork near Jasper, * The average annual runoff is 19.2 inches. 8 , ... - .... --I , I ,, , r ,, ,, -./--- " / - \ /I I --- '- '---", I ",----' I , '- _.... ,' , -"'( I ,,, I I ,, I ,, I I ,, , ,, , ,, I ,, I I I \ , ,, ,, , I ,, I / I ,I , , I I r I LAKE I \ ,, , I ~o OLl'JER LI\K{,-..... --" ,, TUSCALOOSA ,, \ \ r .- I I , I , , r ,, I , ,I , \ , \ I I I ,,, , I ~'il/~~;;;:~L:;'~K~E :' --, " I : ,, ,,, / ll., lL'<l: Figure 1. , WARRiOR - TOMBIGBEE BLACK RIVERS -- --- I ,/ /'-- -', ~~ \ (I)' (1)1 \ ,, ,, ~: I, ,, , COFfEEVILLE LAKE I I \ I I \ L. - .......... I I JOCK o ,, ,, I , I / , ,I I ,, , ,, ,,, I '1------" , I I , I / -' 9 ~ :~~~~~~>4~l:i::;J;;-.J'='J;:.L--WIJL'LJ,~-Jin-LJ,-l~,k...L-JoV....l1:::v,,,l'0ln-11:. J~o v 1 Jo I ,Jo I ! 1~0 ' 2b~ ) E ) MOBILE RIVER .. ""·· .. ·~D"r n'''':D Existing Waterway - Mobile to Demopolis o ,... ,~ ~ o . , ,,> ~~ , '~ ~_'?',\: o~ 2;: 1"." 6"':: - o " 1..,11' - C\ '- "'""" L Nh. ",--t' 230 24 489 5 MI b 9 . ? : 1 "'_:: 25 -' 260 °1 - 270 ; ,"f, ' 'l' N 1-'" ""I 290 280 30u J .. JJO 320 3093 Mi. Figure 2. Telll1eSsee - Tombigbee Ibterway 340 i Ir- 350' l " I 1 9 ( (j o~ - -=.~~ ',Ll'v+4J~Jl~;J¥t"'~' ~ ,-';I\;\,I-~.,,~" ~] ,, , lC U ~ , " POL ~ L C ~ ~o ,i o~~ ~ , < nIlnl (T-- 1 H-41 1""" 3ao :T60 T10 3303M, r I )~'110!lt.j ~ 4 )0 410 Alabama in 1961 to form Lewis Smith Lal'e. At its maximum power pool elevation of 510 feet msl this reservoir covers 21,200 acres and has a maximum depth of 260 feet. The drainage area above the dam is 944 square miles. Smith Lake was constructed primarily for hydropower but secondary benefits include flood-control and water storage for seasonal regulation of streamflow below the dam. Due to the location of the penstock openings and the development of thermal stratification in late summer and fall, Smith Lake tailwaters are occasionally deficient in dissolved oxygen. Inland Lake is a small (1540 acres) impolUldment on Blackburn Fork, a tributary of Locust Fork, near Oneonta, Alabama. This reservoir is used as an indus- trial and domestic water supply by the city of Birmingham, Alabama. depth is 160 feet. Maximum The drainage area above the dam is only 70 square miles. The Sipsey and Mulberry Forks join in eastern Walker County, Alabama, fourteen miles below Smith Dam. At mile 385.4 the Mulberry and Locust Forks combine to form the Black Warrior River. This spot is now covered by Banlffiead Reservoir. John Hollis Banlffiead Lock and Dam is located at river mile 365. 5 near Gal, Grove, Alabama. Banlffiead Reservoir was formed in 1915 and has a surface area of approximately 9,200 acres at elevation 255 feet ms!. the dam is 3,990 square miles. control and recreation. The drainage area above Its uses include navigation, hydropower, flood- Much of the industrial and mlmicipal effluent of Birmingham drains into Banlffiead Reservoir by way of Village, Valley, and Five-Mile Creeks. 11 Holt Reservoir is located at river mile 347. Normal pool elevation is 186.5 feet msl and its maximum normal depth is 82 feet. is 3,296 acres. The area at normal pool There are 4,232 square miles in the drainage area above the dam. Oliver Lock and Dam is located at mile 338. 1 within the corporate city limits of Tuscaloosa, Alabama. Oliver Lake is only S. S miles long, has an area of 675 acres, and is the smallest reservoir on the Warrior River. The normal pool elevation is 124 feet msl. The drainage area above the dam is 4, S2S square miles. Oliver Lake receives the effluent from most of the major industries located in the Tuscaloosa area. The water quality within Oliver Pool is so poor that permanent populations of game fish are found only within a few restricted areas. North River rises in Fayette County, Alabama, and flows southward into Oliver Lake. In 1970, the city of Tuscaloosa constructed a 5, SS5 acre water supply reservoir, Lake Tuscaloosa, on this stream. Tllis reservoir is at elevation 223.2 feet ms1. Although the tailwaters are, at times, low in dissolved oxygen, the 1. 5-mile stretch of North River between the dam and Oliver Lake supports a healthy game fish population. Warrior Lock and Dam is located at mile 261. 1 on the Black Warrior River. This 7,800 acre reservoir provides only navigation and recreation benefits. pool elevation is 95.0 feet msl and the greatest depth is about 50 feet. Normal The drainage area above the dam is 5, S2S square miles. The Black Warrior River joins the Tombigbee River 47 miles below Warrior Dam at river mile 217. Backwaters from Demopolis Dam md:end from this spot to the toe of Warrior Dam. 12 At the present time there are no impoundments on the Tombigbee River proper above Demopoliso Bluff Lake, on the Noxubee River, and Buttahatchie Lake, on the Buttahatchie River, are the only significant impoundments in the watershed. Demopolis Lock and Dam is located at river mile 213.4. la, 000 acres at normal pool 73. a feet msl. This reservoir covers The watershed above this dam is 15,300 square miles. Coffeeville Lock and Dam is located at river mile 116.6. This lake covers an area of 8,500 acres at elevation 32.5 feet msl. The drainage area above this Dam is in excess of 19, 000 square miles. 2-C. Impoundment. The physical characteristics of an inundated basin have considerable influence on the production of fish in the subsequent impoundment. The physical features of Coffeeville Lake which influence the production and harvest of fi sh are listed below. 2-C-1. Morphometry. This stretch of the Tombigbee River is typical of an impounded Coastal Plains stream. freely meandering channel. It has a well developed flood -plain with a Throughout the upper three fourths of this reach of the Tombigbee River the Lake is strictly a run-of-the-river impoundment. In the lower quarter of the lake the river did not overflow its banl, but only flooded low-lying creek bottomlands. Some of these tributaries, all flooded in varying degrees, are listed below. 13 Turkey Creek Okatuppa Creek Tallawampa Creek Copper salt Creek Bashi Creek Big Bunny Creek Ridge Creek Wahalak Creek Sucarbowa Creek Vaughn Creek Horse Creek Tuckabum Creek Landrums Creek 2-C-2. Altitude. 32.5 feet ms!. 2-C-3. Beaver Creek Kinterbish Creek Lost Creek Chicksaw Bogue Six Mile Creek Double Creek Cotahager Creek Cypress Branch Sucarnoochee River Mill Creek Cypress Slough Halls Creek The altitude of Coffeeville Lake at normal upper pool is The elevation of the plains around the lake varies from 50 to 100 feet ms!. Area. At normal upper pool (32.5 feet msl) the surface area of Coffeeville Lake is 8,500 acres with a volume of 190,800 acre-feet. 2-C-4. Mean depth. The mean depth of Coffeeville Lake at normal upper pool is 23 feet. 2-C-5. Maximum depth. The approximate maximum depth is 40 feet at elevation 32.5 feet ms!. 2-C-6. Productive-depth zone. ports most of the aquatic life there. Within a body of water a certain area sup- Several limiting factors determine the lower depth of tills productive zone in a lake. One factor is the depth at which the total quantity of surface light is reduced by 99 percent. Another factor is the depth at which the dissolved oJ-."ygen concentration in the water drops below 1 ppm. Because 14 these two limits vary according to other lake conditions, the 10-foot depth will be considered the approximate bottom of the productive zone. In a riverine environment the productive zone is generally quite variable, depending upon the rate of flow and the sedimentation loading. Current evidence from Coffeeville Lake indicates that phytoplankton is the basic fish-food in the mainstream area, while macro invertebrates are a major food source only in inundated flood plains. 2-C-7. Volumes of euphotic strata. The volumes of the various euphotic strata, which comprise the primary productive areas of lake waters, determine the quantities of nutrients that may be efficiently converted into phytoplankton. The vol- ume of water in each 2. 5-foot strata in Coffeeville Lake is given below. 32.5 to 30.0 30.0 to 27.5 27.5 to 25.0 25.0 to 22.5 below 22.5 2-C-8. feet feet feet feet feet msl msl msl msl msl 20,000 17,000 18,000 14,000 122,000 Length of the shoreline. acre-feet acre-feet acre-feet acre-feet acre-feet The productive zone of a lake, as well as its accessability to bank fishermen, is reflected by the length of its shoreline. This length is also used to calculate the shore development. The shoreline of Coffeeville Lake is approximately 300 miles long and its shore development (which is the ratio between the length of the shoreline and the circumference of a circle whose area is equal to that of Coffeeville Lake) is 23. 2. 2-C-9. Eulittoral zone. The eulittoral zone is the bottom area between the high and low-water levels. Due to the frequent wetting and drying wi thin the eulittoral zone, this area is not considered to be suitable habitat for the production of fish-food organisms. 15 Reservoirs used primarily for navigation, such as Coffeeville Lake, are generally subject to less severe water-level fluctuations that those reservoirs whose primary uses include hydro-power and/or flood control. The loss of fish-food production area due to water-level fluctuations is not great enough in this reservoir to impair fish prod uction. 2-C-10. Inflow. The average flow of the Tombigbee River at Demopolis Lock and Dam is 21,780 cfs. The average flow of the Tombigbee River at Gaines- ville, Alabama is 11,530 cfs. 2-C-11. Outflow. Dam is 26,000 cfs. The average annual discharge at Coffeeville Lock and The estimated 10-year 7-day low flow is 1,100 cfs. Low discharges have occurred periodically from impoundments on the Black Warrior River in the past. Such discharges can interfere with fish production. These conditions are not expected to develop below Coffeeville Lake because the discharge of the Tombigbee River is more stable than that of the Warrior and releases from Smith Reservoir now augment late summer flows in the Black Warrior. 2-C-12. Retention time. Based on an average discharge of 26,000 cfs and an average volume of 190,800 acre-feet, the water exchange rate is 98 times per year, the average exchange time being 3.7 days. Using the estimated 10-year 7-day low flow of 1,100 cfs the water exchange time is 85 2-C-13. Internal flow currents. days. Impoundments on large streams are subject to various types of internal currents. During the cold months the impolmded waters 16 are fairly homogeneous as to temperature, dissolved oxygen, and amounts of suspended matter. This homogeneity is due to the complete circulation of the impounded water. During the warm months the water may stratify thermally and density currents may exist in the lower depths. Normally, there are no density currents in surface waters; instead these waters are subject to wind and convection currents. At the present time there is no evidence to indicate that thermal stratification develops in Coffeeville Lake. During those periods when stream flow is low and temperatures are high, weak thermal stratification may develop in lower portions of the lake. Areas most likely to develop thermal stratification include flooded tributaries, and other backwater sites removed from the main river channel. 2-C-14. Penstock depth. The depth at which the penstock intake openings are located may determine the quality of tailwaters released during power generation. During stratification of lake water, if these openings are below the level in which dissolved oxygen is present, then the tailwaters will be deficient in dissolved oxygen and high in CO 2 , H2 S, and BOD (biochemical oxygen demand). No hydropower facilities exist at Coffeeville Dam. The tailwaters are composed of releases through the navigation lock and over the fixed-crest spillway. Low concen- trations of dissolved oxygen are seldom found in tailwaters drawn from the surface of the impoundment in this manner. To date, no problems with impaired water quality have been observed here. 2-C-15. Water-level fluctuations. Coffeeville Lake was constructed pri- marily as a navigation pool and as such is regulated to minimize water-level fluctu- 17 ations. Water-level fluctuations are not expected to interfere seriously with fish production in Coffeeville Lake, but the rather frequent wave-action from barge traffic plus the continuous agitation of the sandy shore by stream flow has largely eliminated the habitat fish-food organism production. 2-C-16. Uncleared flooded areas. All of the trees were cleared from most of the reservoir below elevation 73 feet msl. The location of the remains of the few clumps of trees left to serve as fish attractors are found in inundated tributaries in the lower reaches of the lake.. 2-C-17. Meteorological influence. Weather conditions are a major in- fluence on the water quality of Coffeeville Lake. Due to the fairly high (and con- stant) exchange rate there is little likelihood that the lake waters will stratify in the Tombigbee River. Heavy rainfall upon any portion of the Coffeeville drainage will produce excessive flow and turbidity in this lake. Such conditions should be expected each spring and may exist during the period when most species of fish will be spawning. 18 3. Water Quality in Relation to Fish Production. 3-A. General. The quality of impounded river waters largely determines the quality and quantity of aquatic life in the lake. The water quality of a river is, in turn, the product of its watershed. The river receives leached, washed-off, and dumped contributions from agricultural, industrial, and urban use of the drainage area. 3-B. Water quality constituents. Since water is the medium in which aquatic plants and animals spend most or all of their existence, water conditions must be optimum for survival, growth, and reproduction of aquatic life. Those water quality parameters that are most important to aquatic life include temperature, dissolved oxygen, pH, carbon dioxide and alkalinity, chemical type (hardness and so forth), plant nutrients, toxic substances, and sediment load. Each of these water quality parameters is discussed below. 3-B-1. Temperature. The water temperature in a lake determines the type of aquatic life that it can support. In the Southeast, water temperatm"es range 0 from about 40 to 95+ 0 F six inches below the sm"face. Generally, weather condi- tions control surface water temperatures, but the activities of man can sometimes alter the temperature of water. Some obvious examples of the latter case are the construction of deep-water impoundments, the winter storage of cold waters, and the release of heated water from industrial cooling systems. 19 3-B-l-a. Temperature stratification in a lake. In all bodies of water there is a tendency for the entire volume to be homogeneous in temperature during the winter period. However, as the air temperature rises in the spring the surface water temperature of a lake also increases. Then as summer approaches, there is an increasing temperature differential between the surface and the bottom waters of a lake. The magnitude of this difference depends upon altitude of the lake, the depth of water, and the quantity and quality of inflowing and outflowing waters. In lakes of sufficient depth the summer thermal pattern starts at the surface layer or epilimnon, where surface temperatures approach or may exceed mid-day air temperatures. Descending in depth, the water temperature decreases until it approaches stratification and may form a thermocline. This is a region in which the water temperature decreases 1 0 for every meter of increasing depth. During the spring the thermal pattern of Coffeeville Lake is typicaIly that of a free flowing river during periods of intermittent flooding. As summer approaches the thermal pattern on the upper reach of the river exhibits thermal characteristics of surface waters in Demopolis Lake and approaches an isothermic status by midsummer. In the lower reach the Lake exhibits some slight decrease in water tem- perature with increasing depth, but even under most adverse conditions of low flow it never approaches a thermocline. The thermal pattern existing in any portion of this lake can be disrupted in warm weather by a heavy summer thunderstorm, by excessive upstream discharges, and in the lower reach by prolonged high winds. 20 3-B-l-b. Temperature conditions in tailwaters. Since the Coffee- ville Dam is a navigation structure where the river flows through gates over a fixed crest spillway, the tailwaters have temperature characteristics almost identical to temperature in epilimnon of Coffeeville Lake. 3-B-2. Dissolved oxygen. Surface waters must contain an adequate supply of dissolved o":ygen in order to support aquatic life. Ranges of dissolved oxygen concentrations in relation to freshwater fish production are shown in Figure 3. Factors which affect the quantity of dissolved oxygen in water include temperatm'e, presence of oxidizable materials, respiration requirements of aquatic plants and animals, and the abundance of phytoplankton. The oxygen-absorbing capacity of water decreases as the water temperature rises. However, the amolmt of oxidizable organic and inorganic materials in the water determines the degree of satm'ation that will be maintained. Although water can absorb oxygen from the atmosphere, such absorption. is limited to the surface layers of lakes. Since a lake needs dissolved oxygen more during the warm weather period when absorption is lower, a more efficient oxygen source is required. phytoplankton. Such a source is provided by microscopic aquatic plants called This biological process is so efficient that waters supporting moder- ate-sized phytoplankton populations can become superstaurated with oxygen. An overabundance of phytoplankton can be detrimental to the overall oxygen situation in a lake. Dense growths reduce the depth to which sunlight can penetrate, which in turn restricts the amolmt of photosynthesis. 21 Thus, oxygen production Pond Fish '"'" Lethal point for pond fish ( Small bluegills may survive if CO is low. 2 J; ppm dissolved 0.1 > Usable range for pond fish I ) 0.2 -v 0.3 1.0 2.0 ::> Desirable range for pond fish 3.0 4.0 5.0 ;,> _ oxyg~en~ I Danger point for stream fish Stream Fish Figure 3. Oxygen content of water and its relation to fish. Ii' Desirable range for stream ! fish ;> occurs near the water surface, while the oxygen demand below this layer is increased by dead plants settling toward the bottom. Also, the dark-period respiration of this dense plant population may utilize most of the previously-produced excess dissolved oxygen. The supersaturation of surface waters resulting from excess oxygen production is not necessarily beneficial to a lake, since much of this supersaturation is lost to the atmosphere if the area is subject to wind-wave action. Dense populations of phytoplankton in lake waters are also undesirable since such populations are subject to die-offs. Such die-offs not only terminate oxygen production in the water, but also create a severe oxygen demand. This generally results in complete oxygen depletion in the lake and the consequent suffocation of aquatic life in the lake habitat. In Coffeeville Lake there are sufficient plant nutrients present to support a moderate growth of phytoplankton, but other conditions have prevented this situation from existing most of the time. There are sufficient growths of phytoplankton, however, to keep the dissolved oxygen concentrations in surface waters at 80 percent or more of saturation during most of the year. 3-B-2-a. Dissolved oxygen stratification in lake. The dissolved oxygen concentrations in CoffeeVille Lake are usually homogeneous during those same cold weather periods when water temperatures are tmiform at all depths. As the surface waters begin to warm up, the dissolved oxygen saturation level decreases. In addition, organic and inorganic oxidation processes begin to speed up and fish and other aquatic life become more active. All of these factors increase the demand for o;.,:ygen. 23 Since the entire reach of Coffeeville Lake has the characteristics of a river, the dissolved oxygen concentration will be fairly uniform from surface to bottom of the Lake throughout most of the year. During periods of low flow and hot weather there may be some decrease in dissolved oxygen from surface to bottom, but it generally will not decrease to a level that endangers fish. 3-B-2-b. Dissolved oxygen conditions in tailwaters. The waters overflowing Demopolis Dam are generally at 75 percent or greater saturation with dissolved oxygen. Such a condition assures that the tailwaters of this dam contain the minimum dissolved oxygen concentration of 4 ppm for a majority of the time in hot weather. 3-B-3. 2!!. The pH of surface waters is a measm'e of whether the water has an acid or basic reaction. In most natm'al surface waters, pH reflects the quantity of free carbon dioxide present. Such waters generally fall in the pH range of 6. 0 to 9.5, which is the range tolerated by freshwater fish (Figure 4 ). Normally, surface waters fluctuate somewhere between these two eJ>.1;remes every 24 hours as a result of photosynthetic activity. Aquatic plants use the CO 2 and sunlight to produce 02 and carbohydrates during the day, thus raising the pH toward 9.5. At night these plants respire, releasing CO 2 and depressing the pH toward 6. O. Some sm'face waters, such as mine drainage wastes, may accumulate acid that has leached from the exposed soil. others may contain acidic or basic wastes from industrial operations. The pH of the waters in Coffeeville Lake fall within the range of 6.0 to 9.5. 24 ACID DEATH POINT < ALKALINE DEATH POINT :;;. ;;roxlc < TO LOW FISH li FIGURE 4. 4 FISH NO REPRODUCTION li JJ 5 RELATIONSHIP RANGE FOR PRODUCTION ~ 3 DESIRABLE 6 OF pH V LOW TOXIC TO PRODUCTION FISH PRODUCTION li , 7 > 8 It 10 9 OF RESERVOIR WATERS FOR FISH PRODUCTION Ji TO THEIR II 12 SUITABlll TY 3-B-4. Carbon dioxide and alkalinity. Most natural waters are buffered by a carbon dioxide-bicarb onate-alkalinity system. The relationships of CO 2 , HC03-' C0 -~ and OH- in natural waters are shown in Figure 5. 3 Carbon dioxide is a natural component of all surface waters. It may enter the water from the atmosphere but only when the partial pressure of carbon dioxide in the water is less than in the atmosphere. Carbon dioxide can also be produced in waters through biological oxidation of organic materials. In such cases, if the photosynthetic activity is limited, the excess carbon dioxide will escape to the atmosphere. Thus, surface waters are continually absorbing or giving up carbon dioxide to maintain an equilibrium with the atmosphere. The alkalinity of natural waters is due to the presence of salts of weak acids. Bicarbonates represent the major form of alkalinity since they are formed in considerable amounts by the activity of carbon dioxide upon basic materials in the soils. Under certain conditions natlll"al waters may contain considerable amounts of carbonate and hydroXide alkalinity. This situation often exists in waters supporting a moderate to heavy growth of phytoplankton. These algae remove free and combined carbon dioxide to such an extent that a pH of 9.0 to 10.0 often exists. 3-B-5. Chemical type. The total hardness, total chloride, and total sulfate content of surface waters indicates its chemical type, particularly where the source of these ions is attributable to the soil formations in the drainage area. Conductance measurements are also included lmder this heading since it may be used to detect changes that may occur in the relative abundance of the above mentioned ions. 26 ~ Total Alkalinity ) ( Bicarbonate Alkalinity ) ( Carbonate and OH Alkalinity ) Range of Occurrence of COS Amount Determined by Titration with HCI. '"..., NaHCOS Range of Occurrence of HCO S-. Amount Determined by Titration with HCI. CO 2 pH = 4.5 Figure 5. ( NaHCO S + HCI ( Na2COS + HCI HCO S Concentration Decreasing 8.S Free OH- Occurs in this Range, Usually Only in Polluted Waters, ) 10.0 11. 0 Relationship and det'9rmination of CO 2 , HCO -, COS --, and OH- in natural waters. S 12.0 lS.0 Total hardness is primarily a meaSLU'e of the total divalent metallic and alkaline earth elements in solution in the water. In most surface waters it measures calcium and magnesium concentrations. The range of total hardness in waters from Coffee- ville Lake varies from 20 38 to ppm as CaC03, with magnesium hardness accounting for about 30 percent of the total concentrations. It should be noted that water hardness is a direct reflection of the geology of the drainage area. Lake waters have an appreciable total hardness only when CO2 em'iched water flows over or through soluble limestone formations on its way to the lake. Total hardness also has a direct bearing upon the total alkalinity of soft water lakes. In this section of the United States the amount of total chlorides generally inclicates the degree of domestic and industrial pollution. In the West, however, total chlorides may reflect the type of drainage area. A ma'''imum concentration of less than 20 ppm total chlorides would be considered normal in waters of Coffeeville Lake. Total sulfates may indicate the type of drainage area. A maximum concentra- tion of less than 50 ppm total sulfates would be considered normal in waters of Coffeeville Lake. Conductance of surface waters depends on the total concentration of soluble ions since this parameter meaSLU'es how well a sLU'face water conducts an electrical current. Conductance is expressed as pmhos/cm 3 . It is useful in fisheries manage- ment in detecting changes in certain soluble elements in the water. In Coffeeville Lake conductance ranged from 123 to 101 }illlhos/cm3 with a mean of 114. 5)lmhos/cm over a 2 year period, 28 3 3-B-6. Plant nutrients. 3-B-6-a. Nutrient enrichment in impoundments. The surface runoff in a river basin is both the solvent and the transporting vehicle for more than 15 elements that are essential nutrients in the growth of aquatic plants and animals. The concentration of these elements in remoff water and eventually in river water depends not only upon the types of soil and agricultural operations that occur in the drainage area, but also upon the amounts of domestic sewage and industrial effluent that may be discharged therein. Once the nutrients reach the impoundment, various things may happen. Some of the nutrients in a lake will always be present in soluble form. These soluble nutrients may originate either from re-solution of bottom muds or from waste and decomposition of plants and animals. Another portion of the nutrients may be precipitated as colloidal matter directly into the bottom muds for temporary or permanent storage. Yet another part of the input nutrient may be used in the growth and reproduction of bacteria, flmgi, algae, or rooted aquatic plants. These plants may be consumed by some animals, or the plants may die and deposit their nutrients in the muds. Animals eliminate most of the nutrients they consume as waste, retaining only a small portion in their growth. The growth-retained portion of nutrients may be removed from the local environment if the animal flies, walks, crawls, or is taken bodily fro111 the impolmdment. If the animal remains in the impoundment, it eventually dies. Then the nutrients retllrn to the bottom muds or become a food item for another animal. 29 Also, a portion of the input nutrients pass out of the impolmdment into the tailwaters and are then classified as outlet nutrients. These outlet nutrients may OCClIT in soluble forms, bacteria, fungi, algae, rooted plants, animals, other organic materials, and soil colloids. All of these nutrients move downstream to combine with additional runoff and eventually become the input nutrients for the next impoundment. There the process is repeated and so on until the river flows into the ocean. What has been described above is an abbreviated nutrient cycle for an impoundment. In order for man to use this cycle to his advantage it is necessary to know both the quantity of each nutrient found in each of the niches descr ibed and the rate of partial or permanent retention. With such information available it is possible to determine the element or elements responsible for over-production of noxious plants, isolate the source(s), and eventually correct the problem. Since the nutrient cycle of an impoundment is intimately related to eutrophication, and since a moderate degree of nutrient em'ichment is essential for fish production in impoundments, a tolerable eutrophication is beneficial. In those areas where there are excessive amounts of nutrients, seasonal rooted aquatic plants may be used as a possible nutrient-retention site during periods of hot weather and frost then provides a mechanism for the slow release of nutrients when there is a higher rate of stream flow. Since elemental nutrients are essential to aquatic life, it is necessary to know how they are distributed in the water, suspended matter (living and dead, organic and inorganic), bottom soils, plants, and fish. to fully evaluate an aquatic habitat. 30 Only with this knowledge is it possible 3-B-6-b. Macro-nutrients. All living things are composed of elements that are arranged in different combinations and configurations to form matter. Those elements which are most abundant in living tissues are called macro-nutrients or major nutrients. Macro-nutrients include carbon, hydrogen, oxygen, nitrogen, phos- phorus, sulfur, potassium, magnesium, calcium, and sodium. The concentrations of some macro-nutrients in various aquatic components of Coffeeville Lake are given in Table 2. Using the mean flow data of the Tombigbee River at Demopolis Dam and the outflow at Coffeeville Dam and taking the average total nitrogen and total phosphorus concentrations in the water at each location, the total daily input and output of these nutrients were calculated for Coffeeville Lake. These estimates for the SWllmers of 1973-'74 are given below. Daily loading as total lbs. Nutrient Lbs/mi 2 Drainage area Nitrogen - input (1) 466,560 30.5 Nitrogen - output (2) 614,496 32.3 Phosphorus _ input (1) 1,728 .11 Phosphorus - output (2) 2,577 .14 (1) Based upon an inflowof21, 780 cfs and a drainage area of 15,300 square miles. (2) Based upon an outflow of 26, 000 cfs and a drainage area of 19,000 square miles. 3-B-6-c. J\llicro-nutrients. In addition to the major nutrients men- tioned above, all liVing things require minute quantities of other elements in order 31 Table 2. Average concentrations of macro-nutrients (elements) in filtered water, suspended matter, bottom soils, rooted plants, and fish from Coffeeville Lake. Macronutrient Nitrogen Phosphorus Filtered Suspended Bottom water, ppm matter, ppm soil, ppm Plants ppm Fish ppm 4.2 .038 .092 1,342 1,630 630 Potassium 2.21 .133 862 28,500 2,255 Magnesium 4.38 .141 1,335 4,080 383 CalciLUn 17.33 .0598 4,237 3,100 509 Sodium 11. 72 .045 1,242 20,800 1,062 32 to survive. Because only a very limited quantity of each element is required, they are called micro-nutrients. Among the micro-nutrients are iron, manganese, copper, zinc, molybdenum, vanadium, boron, chlorine, and cobalt. There are undoubtedly several other elements which eventually will be added to the list, but at present these are the only ones whose active role in liVing organisms is Imown. The micro- nutrient concentration fOlmd in the various components of Coffeeville Lake are given in Table 3. 3-B-6-d. Nutrient SOlLrCes. All nutrients entering Coffeeville Lake come from one of the following sources: the atmosphere, domestic sewage, animal production refuse, animal and vegetable processing waste, fertilizer and chemical manufacturing spillage, other industrial effluents ancl agricultural runoff. The discus- sion here will concentrate on the SOLU'ces of the carbon, nitrogen, and phosphorus that enter this system. In pond culture it has been demonstrated that water, like land, must be properly fertilized to produce sustained high yields of fish. Likewise, large impOlmdments must have a continuous supply of nutrients in order to produce food for fish. Un- fortlmately, large impoundments have unregulated nutrient supplies and in some instances become so over-fertilized that they produce noxious plant growth. To date, even though the supply of nitrogen and phosphorus in Coffeeville Lake has been adequate to produce a moderate phytoplankton growth, other factors have prevented such a growth from developing. Table 3. Averaged concentrations of micro-nutrients (elements) in filtered water, suspended matter, bottom soils, rooted plants, and fish from Coffeeville Lake. Micronutrients Filtered water, ppm Suspended matter, ppm Bottom soil, ppm Plants, ppm Fish, ppm Iron .172 1. 089 3,550 2,320 53.95 Manganese .016 .121 2,030 3,700 5.75 Copper .007 .0212 84.7 .037 91. 25 96 .022 16.9 12 Zinc Cobalt .046 34 0 8.308 164.08 .995 Dissolved carbon is. known to be a limiting factor in development of microscopic plant growths. Runoff waters from the Cumberland Plateau soils are poor in carbon while those from Valley and Ridges Province soils contain moderate quantities of carbon. The main sources of dissolved carbon within the Warrior arm of Coffeeville Lake are combined domestic and industrial wastes from the Birmingham and Tuscaloosa areas. In each of these areas, the varied sources of wastes are in various stages of developing waste treatment facilities to meet the water quality requirements of the Environmental Protection Agency and the Alabama Water Improvement Commission. ApprOXimately 19.4 percent of the Tombigbee River drainage area for Coffeeville Lake lies below Demopolis Dam. There are two large contributors of organic pollu- tion within this area, Gulf State Paper Company and American Can Company. Nutrient sources from the remainder of this portion of the Tombigbee drainage area are primarily agricultmal in origin. 3-B-7. Toxic substances. For many years researchers have recognized that a Ilumber of chemical compolll1ds, alone or in combination with other compolmds, are toxic to fish at low cOllcentrations. For a long time it was impossible to identify exact causative toxicants because of inadequate analytical techniques. In the past decade, however, there have been some outstanding break-tlU'oughs in analytical equipment and now it is possible to detect and identify most of the pollutants in water. Tllis has permitted rapid strides to be made in the control of toxic substances. 35 Only three major groupings of toxicants are known to be present in the Tombigbee River system. These three groups are pesticides, heavy metals, and other industrial toxicants. 3-B-7-a. Pesticides. Pesticides, a product of modern organic chem- istly, were unknown prior to World War II. Since that time the efficacy of most of the insecticides, bacteriacides, fungicides, and herbicides has created an enormous market for tbese products. Unfortunately, some of the compounds are quite toxic to fish, and others are very persistent in either their original or analog form. Tech- niques of application have been devised to minimize the risk of those pesticides which are toxic to fish, and a few such compolmds have been banned from use. In the case of persistent pesticides which acclffilluate in fish tissues, although their detrimental effect upon fish production is questionable, many persons assume that such pesticides consitute a hazard to human health. Consequently, there are now strict regulations concernirg the use of pesticides, particularly in aquatic areas. Needless to say, many insect vector and aquatic weed control practices on large impoundments have been altered. The amounts of pesticides detected in fish from Coffeeville Lake are listed in Table 4. The reSidues from each species are compared with the overall average for that species of fish in all Alabama streams (Table 5). Data on pesticide resi- dues in fish from public fishing lakes in the vicinity of Coffeeville Lake are given in Table 6. 36 Table 4. "" Average concentrations of pesticide residues in fish collected from Coffeeville Lake, 1971. * Concentrations in ppm wet weight of fish Dieldrin Endrin BRC Lindane Species DDT PCB Bass .368 .455 .004 .003 ND ND Carp .530 .750 .010 .003 ND ND Shad .465 .490 .002 .001 ND ND Catfish .222 .348 .003 .001 Toxaphene --J * Data from ND ND Report on Pesticide Residue Content (Including PCB) of Fish, Water and sediment Samples Collected in 1971 from Aquatic Sites in Alabama. Table 5. Average concentrations (ppm wet weight) of pesticide residues in various species of fish collected from the Tombigbee River compared with the overall average from species collected in all rivers in Alabama, 1971.' Carp Sucker Shad 1. 078 .623 .926 1. 829 .698 .209 1. 218 - .004 .008 .011 .008 .006 .015 .012 .006 .007 .009 .001 .002 .002 .002 .006 .004 .003 .003 ND .003 .004 .026 1. 2. 2 - 1. 553 2.232 1. 785 3.091 1.19 3.274 ND ND ND .040 ND .019 ND ND .011 ND ND .013 ND .03 Bass Bluegill Crappie TO AL .533 .923 .785 .485 .276 .526 .551 .647 Dieldrin TO AL .004 .007 .011 .015 .003 .009 Endrin TO AL .003 .003 .007 .003 PCB TO AL .871 1. 645 1.134 1. 523 BEC TO AL .028 .025 .027 .022 Lindane TO AL ND .014 DDT 2.034 Catfish Buffalo 1.105 -ND - 1. 653 5.51 .045 .027 ND ND ND .028 ND .05 ND ND ND .034 'Data from Report on Pesticide Residue Content (Including PCB) of Fish, Water and Sediment Samples Collected in 1971 from Aquatic Sites in Alabama. TO - Samples from the Tombigbee River A L - Overall average of fish from all rivers in Alabama ND - Not detectable 38 2.24 Table 6. Average concentrations (ppm wet weight) of pesticide residues in various s,)ecies of fish collected from public fishing lakes located in the Coffeeville Lake d,rainage area, compared with averages in species from all 23 public fishing lakes in Alabama, 1971. * Bluegill Lam. Mar. Lam. DL AL .071 .263 DL AL .002 DL AL ND Pesticide Site DDT Dieldrin PCB .146 Bass Mar. .253 Catfish Lam. Mar. .100 .294 .125 .004 .001 .001 ND NS .242 .75 NS .528 NS .004 .003 .003 NS .165 ND NS ND DL - Samples from public lakes in the Demopolis Lake drainage area AL - Overall average from fish in all public fishing lakes in Alabama NS - No sample ND - Not detectable Lam. - Lamar County Public Fishing Lake Mar. - Marion County Public Fishing Lake * Data from Report on Pesticide Residue Content (Including PCB) of Fish, Water and Sediment Samples Collected in 1971 from Aquatic Sites in Alabama. 39 3-B-7-b. HeaVY metaJs. There are a number of metallic elements such as lead, zinc, mercury, chromium, cadmium, nickel, and copper that are considered either essential or tolerable constituents of aquatic life when found in limited quantities. In larger amounts, however, these metals may be either toxic or acclUllulative in aquatic organisms. Unfortunately, OlU' Imowledge of the natural occurrence of these elements in the water is limited, and so their true effects upon the environment remain to be determined. Data on the amount of these elements found in the various components of the Coffeeville Lake aquatic habitat are given in Table 7. 3-B -7 -c. Industrial toxicants. Wastes from industrial operations con- tain numerous materials that may be toxic to many or all forms of aquatic life. Many of the substances that were formerly disposed of as wastes are now being reclaimed for reuse in industrial processes. Some llllusable wastes are also removed by treatment, but other toxicants such as cyanides and ammonia are quite difficult to remove from effluents. On the Tombigbee River the industrial wastes that have been most troublesome are organic in nature and have contributed considerably to the BOD loading of the receiving streams. Fortunately, practically all of the industrial plants in the area now have or are in the process of installing adequate secondary treatments for their waste materials. 40 Table 7. Averaged concentrations of heavy metal elements in filtered water, suspended matter, bottom soil, rooted plants, and fish from Coffeeville Lake. Metallic elements Filtered water, ppm Suspended matter, ppm Lead .008 Mercury 00006 Chromium .015 .00075 Cadmium .0073 .0007 Nickel .057 .043 .016 Bottom Soil, ppm Plants, ppm 26.0 0 .045 41 Fish, ppm 2.470 .37 159.87 0 1.008 .75 0 .233 53.57 20 1.513 3 B-8. Sediment load. The sediment load transported by runoff waters depends upon several factors in the watershed. These factors include slope of the land, soil types, quantity and type of land cover, and amount of construction on the watershed. In addition, the seasonal rate and duration of rainfall in the drainage area influences the sediment load of rLIDoff waters. The Upper Warrior River drainage area occupies a topographic region with moderately steep hills and relatively narrow valleys, while the Tombigbee River drainage area occupies a region of moderate hills and relatively wide valleys. The soils within the Warrior Basin are moderately erodible, but due to the extensive impoundment system on this basin a great part of the runoff sediment load is retained within this basin. The soils within the Tombigbee Basin are typical Upper Coastal Plain Province derivatives that are also moderately erosive. Since these soils are mainly clays, the silt loading of runoff waters is mainly of a colloidal natm'e. Even though there are rather extensive impoundages on the Warrior River, the colloidal loading of flood waters is not all retained within the basins. Thus, flood waters entering Coffeeville Lake from Warrior drainage basin may be rather turbid. The Upper Tombigbee River drainage basin has upstream land characteristics similar to those on the Warrior Basin, while downstream land features are typical of those fOLIDd within the Black Belt Soil formation. There are no impoundments on this River that would decrease its sediment load into Coffeeville Lake. The average turbidity within Coffeeville Lake during SLUnlller of 1974 was 25 JTU's. 42 3-C. Pollution sources. The sources are generally identical to the nutrient enrichment sources listed in Section 3-B-5-d. As a matter of record, the 1973 point sources of waste disposal on the Black Warrior - Upper Tombigbee - Lower Tombigbee Rivers above Coffeeville Dam are given in Tables 8, 9, and 10. Where available, the discharge rate and the status of the waste treatment facility at each point source are included in the tables. Even though these treatment facilities have been efficient in reducing the quantity of dissolved carbon released into the river, large amounts of nitrogen and phosphorus are still released in the treated effluent. Waste treatment benefits fisheries management most by the reduction of disease organisms, solid waste (biodegradable carbonaceous materials), and certain nitrogen and phosphorus compounds in the water. Inadequacies of present-day treatment facilities include the apparent inability to retain a greater fraction of the nitrogen and phosphorus compounds in their sludge, and their present limited capacity for handling storm sewer runoff. A large portion of the pesticide and some of the nitro- gen compounds detected in rivers adjacent to and below sewage outfalls probably were contributed by storm sewer runoff. 43 Table 8. Black Warrior River waste sources Location Population HHIT Empire Coke Tuscaloosa Treatment status OK/OK 65,000 Kellerman Coal OK Reichold Chemical HHIT Warrior Asphalt OK Central Foundry OK Gulf States Paper IT Northport 8,000 OK/OK Hunt Oil Co. IT B. F. Goodrich OK Eutaw 3,000 SWOC/OK Moundville 2,000 SWOC/OK Greensboro 3,000 SWOC/OK Fayette 5,000 SWOC/OK Berry 1,000 SWOC/OK Arab 2,000 OK/OK Carbon Hill 1,000 HHPT/BOTH Parrish 1,000 SWOC/OK Vulcan Asphalt Jasper IT 20,000 OK/SBEL 44 Remarks Black Warrior River waste sources (cont'd.) Treatment status Location Population Sumiton 2,000 SWOC/OK Cordova 2,000 SWOC/OK Cullman 11,000 SWOC/SBEL Daubert Chemical OK Poultry By-Products OK Valley Creek STP 100,000 HHPT/BOTH Woodward Iron IT McGraw-Edison (Fibre) OK Hackney Corp. OK Village Creek STP u. 32,000 HHPT/BOTH S. Steel IT Allied Chemical IT Republic Steel IT McGraw Edison (Power) OK Stockham Valves OK Army Aviation OK Hayes International OK Metalplate and Coatings IT Birmingham Hide and Tallow OK Birmingham Plating Works IT 45 Remarks Black Warrior River waste sources (cont'd.) Location Population Treatment §tatus American C. I. Pipe IT S. E. Metals Co. OK Five Mile STP 15,000 HHPT/BOTH Alabama By-Products OK Alabama By-Products IT Vulcan Rivet and Bolt OK U. S. Pipe and Foundry IT James B. Clow Co. UK John Hauser Co. IT Dolcita Quarry OK U. S. Pipe (Coal Washer) OK U. S. Pipe (Flat Top Mine) OK Roberts Galvanizing IT Pan National Fence IT Dixie Electrical Mfg. IT Connector Products IT Republic Steel IT Turkey Creek STP 2,000 OK/OK Spring Valley Farms Blountsville HHIT 1,000 HHPT/BOTH 46 Remarks Black Warrior River waste sources (cont'd.) Location Population Abbott Farms Oneonta Treatment status IT SWOC/EL5 4,000 47 Remarks Table 9. Upper Tombigbee River waste sources Location Population Treatment status Haleyville 2,000 OKIOK Winfield 3,000 SWOC/OK Guin 2,000 SWOC/OK Hollywood Vasarette OK Hamilton 2,000 SWOC/OK Vernon 2,000 PS/BOTH Sulligent 1,000 HHNT/BOTH Brown Wood Pres. OK Huyck Felt IT Gorda 2,000 SWOC/OK Carrollton 1,000 SWOC/OK Aliceville 2,000 SWOC/OK Reform 3,000 HHPT/BOTH 48 Remarks Table 10. Lower Tombigbee Waste sources Location Livingston Population 4,000 SWOCIOK Sumter Plywood York OK 3,000 SWOCIOK Cumberland Gulf Jackson UK 4,000 SWOCIOK Allied Paper Grove Hill Treatment status IT 3,000 PS/BOTH American Can IT Demopolis 6,000 SWOCIOK Linden 2,000 aKiaK Gulf States Chatom IT 1,000 SWOCIOK Olin Corp. Alabama Electric Co-op. OK Geigy Chemical IT 49 Remarks TREATMENT CLASSIFICATIONS For Municipal Dischargers: HHIS - Health Hazard with Individual Treahnent Systems HHNT - Health Hazard with No Treatment (Raw Discharge) HHPT - Health Hazard with Primary Treahnent PS - Primary System SWOC - Biological (or equivalent) Treatment without Chlorination OK - Minimum of Biological Treatment (or equivalent) For Industrial Dischargers: HHNT - Health Hazard with No Treatment (Raw Discharge) HHIT - Health Hazard with Inadequate Treatment IT - Inadequate Treatment OK - Adequate Treatment LOADING CLASSIFICATIONS Municipal Dischargers Only: SHEL - Significant Hydranlic Efficiency Loss SBEL - Significant Biological Efficiency Loss Both - Both of the above Conditions Exist EL2 - Efficiency Loss (Either Type) Expected Within 2 years EL5 - Efficiency Loss (Either Type) expected Within 5 years OK - No Overload Anticipated for 5 years 49 - A 4. Aquatic Plants in the Impoundment. 4-A. Aquatic plant - definition. The term "aquatic plant," as used in this Plan, refers to a multitude of plant species (including some bacteria and fungi) whose entire life cycle is passed within an aquatic environment. Practically all aquatic plants may be desirable at one time or another in a particular habitat. However, when they become too dense or interfere with other uses of the water, they become a nuisance. 4-B. Factors affecting aquatic plant growth. Bodies of water are like land areas in that some type of vegetation \vill occupy any suitable habitat. Likewise, the more abundant the nutrient supply, the more dense the vegetation, other environmental factors being favorable. to be determined. AII nutrients essential for plant growth are yet Some of the elements known to be important are nitrogen (N), phosphorus (P), potassium (K), magnesium (Mg), calcium (Ca), manganese (Mn), iron (Fe), silicon (Si) for diatoms, sulfur (S) as sulfates, o'q'gen (02), and carbon (e) as carbonates. In many habitats an abundance of nitrogen and phosphorus pro- motes vegetative production if other conditions for growth are favorable. Most algae require some simple organic compounds, such as amino acids and vitamins, and many trace elements, such as zinc and copper. It must be remembered that factors other than plant nutrients also are operative in the establishment and maintenance of aquatic plant growths. For the process of photosynthesis to occur, there must be sufficient light reaching the critical point in 50 the habitat. If turbidity from muds, dyes, other materials, or even phytoplankton is too great, plants at lower depths cannot grow. However, certain plants, if established in an area, can trap large amounts of intermittent silt and other materials, and clear the waters for downstream uses. Another factor that might be operative in preventing aquatic plant growth would be the lack of free C02 and bicarbonate ions in a particular aquatic environment. Certainly an area in which the pH is high, 9.5 or above, or low, below 5.5, productivity would not reach high levels due to a lack of sufficient bicarbonates. Temperature also is an important factor in determining the amount of growth. For each species there is an optimum range in which the greatest growth occurs. Wave action on large eXllanses of water may also be a factor in regulating all types of aquatic plant growths. This appears contradictory to the concept that winds cause mixing of surface and bottom waters, thereby renewing plant nutrients in the euphotic zone. However, in certain lakes and reservoirs, wind induced waves and currents mechanically agitate bottom materials and waters to an extent that interferes with the production of phytoplankton and rooted aquatic plants. 4-C. Aquatic plant groups and associated habitat problems. The plants that occupy an aquatic habitat may be divided into bacteria, fungi, algae, and rooted or floating flowering plants. In the paragraphs which follow there is a brief summary of the characteristics of each plant gronp and the problems the plants may create. 51 4-C-1. Bacteria. Members of the group of sheath-formers are the pri- mary bacterial nuisance in rivers, lakes and ponds. A notable problem associated with this group occurs in areas subjected to organic enrichment. Bacteria, espe- cially of the genus Sphaerotilus, are prevalent in areas receiving raw domestic sewage or improperly stabilized paper pulp effluents containing a small amount of simple sugars. The bacterial growths interfere with fishing by fouling lines, clogging nets, and generally creating unsightly conditions in an infested area. Their metabolic demands while living and their decomposition after death also cause the bacteria to impose a high BOD load on the stream, which can severely deplete dissolved ohygen. Furthermore, it has been reported that large populations of Sphaero- tilus render the habitat noxious to animals and thus actively exclude desirable fish and invertebrates. There are no known growths of Sphaerotilus in Coffeeville Lake. 4-C-2. Fungi. No information. 4-C-3. ~. The freshwater algae are quite diverse in shape, color, size and habitat. In fact, describing all the species of algae would be as compre- hensive as writing about all the land plants, including fungi, mosses, ferns, and seed plants. Algae may be free-floating (planktonic) or attached to the substrate (benthic or epiphytic types). They may be macroscopic or microscopic and are single-celled, colonial, or filamentous. When present in sufficient numbers, these plants impart 52 color to the water, varying from gTeen to yellow to red to black. They may also congTegate at or near the water surface and form a scum or waterb loom. Algae form the first link in the aquatic chain which converts inorganic constituents in the water into organic matter. During the daylight hours algae photosyn- thesize, thus removing carbon diol\ide from the water and producing ol\ygen. Algae also produce carbon dioxide by their continual respiration. The amount of Ol\ygen produced by algae during active photosynthesis is generally in excess of the amount of carbon dioxide released by respiration. Limited concentTations of algae are not troublesome in surface waters, but an overabundance of various species is undesirable for many water uses. A relati vely abundant gTowth of phytoplankton in waters 3 or more feet deep shades the bottom muds enough to prevent germination of seeds and halt the gTowth of practically all rooted sumbersed and emersed aquatics. This removes an important source of food for ducks and other waterfowl. Some gTeen algae, blue-gTeen algae, and diatoms produce odors and scums that make water less desirable for swimming. Also, people who are allergic to many species of algae are affected if the algae become very numerous iu waters used for swimming. Dense gTowths of such phytoplankton and filamentous algae may limit photosyntlletic activity to a surface layer only a few inches deep. Under certain conditons the populations of algae may die and their decomposition will deplete dissolved oxygen in the entire body of water. 53 A number of algal species reportedly cause gastric disturbances in humans who consume the infested water. Under certain conditions, several of the blue- green algae produce toxic organic substances that kill fish, birds, and domestic animals. The genera that contain species which may produce toxins are Anabaena, Anacystis, Aphanizomenon, Coelosphaerium, Gloeotrichia, Nodularia, and Nostoc. Species of the g~reen algae, ChI orella, have also caused toxicosis. Many forms of phytoplankton and filamentous algae clog sand filters in water treatment plants, produce undesirahle tastes and odors in drinking water, and secrete oily substance that interfere with manufacturing processes and domestic water use. Certain algae cause foaming of water during heating, corrosion of metals, or clogging of screens, filters, and piping. Algae may also coat cooling towers and condensers, causing these units to become ineffecti ve. Filamentous algae in ponds, lakes, and reservoirs may deplete the nutrient supply of the unicellular algae which are more commonly eaten by fish or fish-food organisms. Dense growths of filamentous algae may also reduce total fish production and seriously interfere with harvesting the fish by hook and line, seining, or draining. Under certain conditions, these growths on pond and lake bottoms be- come so dense they eliminate fish spawning areas and possibly interfere with the production of invertebrate fish food. However, the amount of cover provided by such large growths of filamentous algae can contribute to enormous population increases, resulting in large numbers of small stunted fish. A list of various genera of algae collected from Coffeeville Lake is gi ven in Table 11. 54 Table 11. List of phytoplankton genera collected from Coffeeville Lake in 1974. Chlorophyta Actinastrum Chlamydomonas Dictyosphaerium Scenedesmus 8elenastrum Euglenophyta Phacus Trachelomonas Chrysophyta Asterionella Unidentified diatoms Cyanophyta Spirulina 55 4-C-4. Flowering plants. floating, and marginal plants. This group includes submersed, emersed, These aquatics may be rooted in the soil or they may have roots which float at or near the water surface. Submersed plants are those which produce most or all of their vegetation beneath the water surface. These plants often have an underwater leaf form totally different from the floating or emersed leaf form. The flowers usually grow on an aerial stalk. The abundance of these weeds depends upon the depth and turbidity of the water and also upon the type of bottom. In clear water 8 to 10 feet is the maxi- mum depth of their habitat, since they must receive enough light for photosynthesis when they are seedlings. Most of these submersed aquatics appear capable of ab- sorbing nutrients and herbicides through either their roots or their vegetative growth. Emersed plants are rooted in bottom muds, but produce most of their vegetation at or above the water surface. Some species have leaves that are flat and float entirely upon the surface of the water. Other species have saucer-shaped or irregular leaves which do not float entirely upon the water surface. Marginal plants are probably the most widely distributed of the rooted aquatic plants and are quite varied in size, shape, and habitat. Many species can grow both in moist soils and in water up to 2 feet deep. Other species grow only in moist soils or only in a water habitat. Floating plants have t11.1e roots and leaves, but instead of being anchored in the soil they float about on the water surface. 111e plants are buoyant due to modifications of the petiole and the leaf, including the covering of the leaf surface. Most species ha ve well-developed root systems which collect nutrients from the water. 56 Species designated as weeds are not necessarily such in all places and at all times. For example, many submersed and emersed plants that normally interfere with water recreation are considered desirable food sources in waterfowl refuges. Rooted plants with floating leaves (e. g., waterlilies and watershield) and those plants which float upon the surface (e. g., waterhyacinth, parrotfeather, alligatorweed, and duckweeds) are considered highly objectionable by many water users. However, in clear water areas where artificial or natural fertilization is moderate, removal of these surface-shading plants permits sunlight to penetrate to the bottom muds and thus submersed plants may soon occupy these waters. These submersed plants geuerally are considered more objectionable than the original surface-covering plants. Most emersed and marginal plants and a few sumbersed plants plus filamentous algae provide a suitable habitat for the development of anopheline and other pest mosquitoes. They also furnish a hiding place for snal<es and are an excellent habitat for damselflies and some aquatic beetles. Like filamentous algae, flowering plants consume llutrients that cou Id otherwise by used by phytoplankton. Thus, an overabundance of rooted plants may reduce total fish production in an infested body of water and interfere with harvesting the fish. There is also evidence that rank growths of submersed, emersed, or floating weeds may deplete the dissol ved oxygen supply in shallow waters. This causes fish to move into more open and better quality water, if such water is available. Ex- tensive growths of weeds can, however, provide so much cover that the fish popu- 57 lation increases enormously, resulting in overcrowding and stunting. A listing of the potentially noxious flowering aquatic plants in Coffeeville Lake is given in Table 12. 4-D. Aquatic plant populations of Coffeeville Lake and methods for their control. The majority of the shoreline on the mainstream portion of Coffeeville Lake consists of shifting sands that are moved with each rising water. On the lower tributary streams and flooded swamps, there are extensive marginal stands of alligatorweed, with lesser stands of Leersia, American lotus, lizardtail, and Sagittaria. Stands of cutgrass are currently limited, but as the banks become stabilized, the growth of this plant is anticipated to expand. Cattails are very scarce and their spread is not anticipated to be great in the future unless the banks become very stable. The stands of alligatorweed were all inhabited by the Argentine flea beetle, but the degree of control evident in June, 1974, was variable. The factors responsible for the slow beetle damage could have been high waters and cool nights. It is anti- cipated that as the summer progresses that the beetle population will expand and largely control the growths of alligatorweed. 58 Table 12. List of the noxious flowering aquatic plants in Coffeeville Lake. cattails arrowhead cutgrass Giant cutgrass Lizardtail Alligatorweed American lotus (yellow lotus) Typha sp. Sagitta ria sp. Leersia sp. Zizaniopsis miliacea Saururus cernuus Alternanthera philoxeriodes Nelmnbo lutea 59 5. Description of the Fishery. Prior to, and tlu'oughout the time this impoundment has existed very limited studies have been conducted to determine the species of fish present, the abundance of each species in the total population, the condition of individuals of each species, the availability of fish-food organisms, and the prevalence of disease and parasite infestations. The available information on each of these aspects of the Coffeeville Lake fishery is summarized in this section. this report was gathered in 1974. Most of the information presented in Limited pre-impolmdment data on the stretch of stream included in this lake are available for comparative purposes. 5-A. Warmwater species of fish in Coffeeville Lake. The earliest studies of the fishes in the Tombigbee River system were conducted in the 1870's. Since that time several ichthyologists have collected in this area and have added to the total list of species that have existed in this stretch of the river. These findings were summarized in 1968 by Smith- Vaniz, and a check list of known and doubtful species that currently exist was prepared. The warmwater species comprising this list were divided into three groups; sport, commercial, and miscellaneous as presented in Table 13. The separation of the species of fish in the Tombigbee River into sport, commercial, and miscellaneous categories is not wholly justifiable in the overall ecology of any particular aquatic habitat. The sport fish consists of those species generally sought by the various types of hook and line fishermen. Thus, in a true sense the catfish should be included in this group because many bank fishermen would prefer 60 Table 13. A check list of warmwater fish species believed to be present in Coffeeville Lake, separated into Game, Commercial, and Other groupings. * Game Species Redfin pickerel Esox americanus Chain pickerel White bass Morone chrysops Yellow bass Morone mississippiensis Stri ped bas s Morone saxatilis Rock bass Ambloplites rupestris Flier Centrarchus macropterus Warmouth Chaenobryttus gulosus Green sunfish Lepomis cyanellus Orangespotted sunfish (intro.) Lepomis humilis Bluegill Lepomis macrochirus Dollar sunfish Lepomis Inarginatus Longear sunfish Lepomis megalotis Red-ear sunfish Lepomis microlophus Spotted sunfish Lepomis punctatus Spotted bass Micropterus punetulatus Largemouth bass Micropterus salmoides Wh ite crappi e Pomoxis annularis Black crappie Pomoxis nigromaculatus Sauger Stizostedion vitreum 61 Table 13, cont'd. Commercial Species Paddlefish Polyodon spathula American eel Anguilla rostrata Carp (introduced) Cyprinus carpio Quillback Carpiodes cyprinus Highfin carpsucker Carpiodes velifer Blue sucker Cycleptus elongatus Creek chubsucker Erimyzon oblongus Lake chubsucker Erimyzon sucetta Sharpfin chubsucker Erimyzon tenuis Alabama hogsucker Hypentelium etowanum Smallmouth buffalo Ictiobus bllballls Spotted sucker Minytrema melanops River redhorse Moxostoma carinatulU Blacktail redhorse Moxostoma poecilurum Blue catfish Ictalurus fllrcatus Black bullhead Ictallurus rnelas Yellow bullhead IctalLurus natalis Brown bullhead IctalLurus nebulosus Channel catfish Ictalurus punctatus Flathead catfish Pylodictus olivaris Freshwater drum Aplodinotus grunniens striped mullet Mugil cephalus 62 Table 13, cont'd. Miscellaneous Species Chestnut lamprey lchthyomyzon castaneus Southern brook lamprey Ichthyomyzon gagei Least brook lamprey Lampetra aepyptera Shovelnose sturgeon Scaphirhynchus platorynchus Spotted gar Lepisosteus oculatus Longnose gar Lepisosteus osseus Alligator gar Lepisosteus spatula Bowfin Amia calva Alabama shad Alosa alabamae Skipjack herring Alosa chrysochloris Largescale menhaden B revoortia patronus Gizzard shad Dorosoma cepedianum Threadfin shad Dorosoma petenense Bay anchovy Anchoa mitchilli Mooneye Hiodon tergisus Stoneroller Campostoma anomalum Silverjaw minnow Ericymba buccata Cypress minnow Hybognathus hay i Silvery minnow Hybognathus nuchalis Speckled chub Hybopsis aestivalie 63 Table 13, cont'd. Miscellaneous Species, cont'd. Bigeye chub Hybopsis amblops Silver chub Hvbopsis storeriana Bluehead chub Nocomis leptocephalus Golden shiner Notemigonus crysoleucas Rough shiner Notropis baileyi Pretty shiner Notropis bellus Ironcolor shiner Notropis chalybaeus Striped shiner Notropis chrysocephalus Fluvial shiner Notropis edwarc1raneyi Pugnose minnow Notropis emiliae Sailfin shiner Notropis hypselopterus Taillight shiner Notropis maculatus Cherryfin shiner Notropis roseipinnis Silverband shiner Notropis shumardi Flagfin shiner Notropis signipinnis Silverstripe shiner Notropis stilbius Weed shiner Notropis texanus Blacktail shiner Notropis venustlls Mimic shiner Notropis voillcelllls Bluenose shiner Notropis welaka Sandloving shiner Notropis sp. cf. longirostris 64 Table 13, cont'd. Miscellaneous Species, cont'd. BlLmtnose minnow Pimephales notatus Bullhead minnow Pimephales vigi lax Creek chub Semotilus atromaculatus Black madtom Notm"llS flmebris Tadpole madtom NoturllS gyrinlls Speckled madtom Noturus leptacanthus Freckled madtom NOtllrllS nocturnlls Pirate perch Aphredoderus sayanlls Atlantic needlefish Strongylura marina Starhead topminnow FtUldlllus notti Blackspotted topminnow Fundulus olivaceus Mosquitofish Gambusia affinis Brook silverside Labidesthes sicculllS Banded scuipin Cottus carolinae Banded pygmy sunfish Elassoma zonatllln Crystal darter Ammocrypta asprella Naked sand darter Ammocrypta beani Scaly sand darter Ammocrypta vivax Bluntnose darter Etheostoma chlorosomllm Swamp darter Etheostoma fllsiforme 65 Table 13, cont'd. Miscellaneous Species, cont'd. Harlequin darter Etheostoma histrio Johnny darter Etheostoma nigrum Goldstripe darter Etheostoma parvipinne Cypress darter Etheostoma proeliare Rock darter Etheostoma rupestre Speclded darter Etheostoma stigmaeum Gulf darter Etheostoma swaini Redfin darter Etheostoma whipplei Blackwater darter Etheostoma zoniferum Etheostoma (ffiocentra) sp. Logperch Perchk'! caprodes Blackside darter Percina maculata Blackbanded darter Percina nigrofasc ia ta River darter Perc ina shmnardi stargazing darter Perc ina uranidea *Data from William F. Smith- Vaniz, Freshwater Fishes of Alabama (1968); and Dr. John S. Ramsey, Auburn University Department of Fisheries and Allied Aquacultures. 66 these species over most others in the river. Likewise, the commercial group includes those species generally sought by commercial fishermen. These are those species that are allowed (by law) to be openly sold in commerce. This is an understandable regulation since these are the most abundant species of edible fishes in most rivers. The name of the third group, miscellaneous, implies that this group of species are of no value since they are not consunled by humans. In many sportsmen's minds this means that these species are wholly detrimental to sport and commercial fish production in rivers and large impoundments. This is an erroneous conclusion for each of these species has a role in maintaining a "balance of nature" in the particular habitat where they exist. Certainly the feeding habits of many of these species of non-game and non-commercial species must be e;..'tremely beneficial in the break down of many organic materials which enter and tend to accumulate in surface waters. Their conversion of this waste into food for the more desirable game and commercial species of fish is one major aim of reservoir fisheries management. In concluding the discus sion of this grouping of species of fishes from the Tombigbee River, let it be made clear that no information exists which would indicate that anyone of these species should be eliminated. Under certain conditions the expansion of the population of one or more species may diminish the production of more desirable species within the impoundment. It is the purpose of fisheries management to prevent or correct such unfavorable conditions when they develop. 5-B. Cold water species of fish in Coffeeville Lake. 67 None. 5-C. The downstream species from Coffeeville Dam. According to the best information available today, the same species of warmwater fish exist in the tailwater that exist in Coffeeville Lake. 5-D. Rare and endangered species. The Department of Conservation and Natural Resources has prepared a list of all those species of fish that might be considered rare or endangered in the surface waters of Alabama. Prior to the construction of Coffeeville, Demopolis, and Warrior Dams the salt-water striped bass, Morone saxatilis, migrated up this stream. Whether or not it spawned in this stream is unknown. Since the closure of these Dams there has been no up- stream migration and no recorded spawning by any impounded striped bass on this drainage basin. 5-E. Fish-food organisms. In 1974 a limited biological survey was made of the Tombigbee River Basin between Coffeeville and Demopolis Dams by personnel of Auburn University's Department of Fisheries and Allied Aquacultures. The information presented in tlils Plan was obtained from hand-picked samples collected at various points on the Lake. During the collection of samples biologists noted hatches of adult mayflies. The presence of these insects indicated that this aquatic habitat was suitable for the production of fish-food organisms. A listing of the macroinvertebrate forms collected from Coffeeville Lake in 1974 are presented in Table 14. 68 Table 14. Macroinvertebrates from weed samples taken from Coffeeville Lake. Crustacea Amphipoda ~yalella azteca Insecta Hemiptera Abeclus Plea Trichoptera Oecetis (2 spp. ) Agravlea Diptera Polypedilum Tribelos 69 While a diversity of organisms was obtained during' this study, and it was generally concluded that they indicated that these river waters were suitable media for their reproduction and development, the quantitative data did not indicate their presence in any great ablmdance. It appears that the liquid portion of the habitat was very satisfactory for the development of macroinvertebrates, but the configuration of the stream channel was generally too deep and shifting of the sandy banks was too extensive for this development to occur. As pointed out previously, Coffeeville Lake is a moderately deep run-of-theriver impoundment, and is largely unsuitable for bottom organism production. On the other hand it does produce a fair population of phytoplankton and must depend upon this as its primary source of fish-food organisms. 5-F. History of parasite and disease incidents in fish populations. For the years that Coffeeville Lake has been impounded there have been incidents of fish mortality when all water quality parameters have been ideal for fishes to grow and reproduce. One major cause of warm weather fish kills has been a bacterial infection caused by the group called Aeromonas. Generally this type of infection is recog- nized by the large, red, boil-like lesions on the body of the fish. Two factors, operative in the springtime, tend to incite the spread of both parasite and disease infections. One factor is a rising water temperature, that provides the optimunl parasite and disease development range (65 to 75 0 F). A second factor is that this temperature range is the same that stimulates fish spawning and many species of sunfishes and basses are congregated and sweeping nests. 70 Thus there is crowding of fish into a restricted area, and these fish are aggressive and strongly defend their nesting territory. This results in much physical contact and fighting among many individuals and provides ideal condition for spread of infections. Another factor is that the fishes condition is generally at its lowest ebb during this early spring period making the fish more susceptible to diseases and parasite attacks. Current trends in fish disease and parasite infections in lakes of the Southeastern United states indicate that infections are generally more prevalent during warmer months, but may occur in varying degrees throughout the year. Also, it has been noted that under certain conditions the spread of infections may intens ify over a period of several years. These are numerous bacteria plus viruses and parasites that have been isolated and identified from fish collected throughout the Mobile River basin. These listings are presenta:! in Tahles 15 and 16. Needless to say, the loss of mostly harvestable-sized fish to disease and parasite infections is undesirable, nevertheless it indicates that considerably more harvestable-sized fish were present in the lake than are being harvested by the fishermen. To date no satisfactory treatment has been devised that could be used to combat the spreading of disease and parasite infections among the fish population in Coffeeville Lake. 5-G. History of fish kills. During the 17 years that Coffeeville Lake has been impounded there was one major fish kill below the outfall of Gulf state Paper 71 Table 15. r. Amiidae Fish parasites in the Mobile River Basin * Cestoda Haplobothrium Proteocephalus Acanthocephala Neoech inorhynchus II. Anguillidae III. Catostomidae Crustacea Ergasilus Fungi Saprolegnia Protozoa Glossatella Myxobilus Myxosoma Trematoda Anoncohaptor Aplodiscus Daety logyrus Gyrodaclylus Myzotrema Octomacrum Pellucidhaptor Pseudomurraytrema Triganodistomum Cestoda Biacetabulum Isoblaridacris Monobothrium Proteocephalus Nematoda Capillaria Philometra Spinitectus 72 Table 15 (cont'd.) III. (cont'd.) Acanthocephala A canthocephalus Neoechinorhynchus Pilum Leech Piscicolaria Placobdella Crustacea Argulus Ergasilus IV. Centrarchidae Fungi Saprolegnia Protozoa Epistylis Myxobilatll s Trichodina Myxosoma Glossatella Myxidium Trematoda Actinocleidlls Anchoradiscus ClavlInculus Crepidostomum Cryptogonimus Gyrodaetylus Lyrodiscus Neasclls Phyllodistomum Pisciamphistoma Posthodiplostomum Urocleidus Cleiclodiscus Uvelifer Leuceruthenls Clinostomum 73 Table 15 (cont'd.) IV. (cont'd.) Cestoda Botllr iocephalu s Haplobothrium Proteocephalus Nematoda Camallanus Capillaria Contracaecum Hedruris Philometra Spinitectus Spiroxys Acanthocephala A canthocephalus Eocollis Leptorhynchoides Neoechinorhynchus Pilum Pomphyrhynchus Leech Cystobranchus Illinobdella Pisciolaria Crustacea Ergasilus Actheres Lernea Mollusca Glochidium v. Clupeidae Protozoa Ichthyophthirius Plistophora Trichodina Scyphidia 74 Table 15 (cont'd.) V. (cont'd.) Trematoda Pseudoanthocotyloides Mazocraoides Cestoda Bothriocephalus Nematoda Capillaria Hedruris Acanthocephala Gracilisentis Tanaorhamphus Crustacea Ergasilus VI. Cyprinidae Protozoa Epistylis Glossatella Ichthyophthirius Myxobilatus Myxosoma Trichodina Scyphidia Trematoda A lloglossidium Crepidostomum Dactylogyrus Gyrodactylus Neascus Posthodiplostomum Pseudacolpenteron Cestoda Atracto Iytocestus Biacetabulum Khawia Penarchigetes Proteoecephalus 75 Table 15 (cont'd.) VI. (cont'd.) Nematoda Rhabdochona Leech Placobdella Crustacea Argulus Ergasilus Lernaea Mollusca Glochidia VII. Esocidae Trematoda Crepidostomum Cestoda Proteocephalus Nematoda Heclruris Phil ornetra Rhabdochona Acanthocephala Neoechinorhynchus Pilum Crustacea Ergasilus Lernaea VIII. Ictaluridae Fungi Saprolegnia Protozoa Chiloclon Costia Glossatella Henneguya Ichthyophthirius 76 Table 15 (cont'd.) VIII. (cont'd.) Protozoa (cont'd.) Scyphidia Trichodina Trichophrya Trematoda Alloglossidium Cleidodiscus Clinostol11um Gyrodactylus Phyllodistol11um Posthodiplostol11um Cestoda Corrallobothrium Nematoda Contracaecul11 Raphidascaris Spinitectus Acanthocephala Neoechinorhynchus Leech Cystobranchus Crustacea Achtheres Argulus Ergasilus Lernaea IX. Lepisosteidae Trematoda Didymozeidae Cestoda Proteocephalus Nematoda Hedruris 77 Table 15 (cont'd.) IX. (cont'd.) Crustacea Argulus Ergasilus X. Polyodontidae - Trematoda Diclybotbrium Cestoda Marsipometra Nematoda Camallanus Crustacea Ergasilus XI. Sciaenidae Trematoda Crepidostomum A lloglossidium Nematoda Contracaecum Cystidicola Crustacea Ergasilus Lernaea Mollusca Glochidia * Based largely on class collections; slides in possession of Dr. Wilmer A. Rogers, Auburn University Department of Fisheries and Allied Aquacultures. 78 Table 16. Viral, bacterial and fungal diseases of r'Olservoir fish * Catostomidae Viruses - None Bacteria Aerolllollas liquefaciens (Syn. :.A. hydrophila, A. pUllctata) Pseudomonas fluorescens Chondrococcus colunU1aris Fungi Saprolegnia Achlya Centrarchidae Viruses Lymphocystis Bacteria Aeromonas liguefaciens (Syn, : A. hydrophila, A. pUllctata) Pseudolnonas flourescens Chondrococcus columnaris Fungi Saprolegnia Achlya Branchiomyces Clupeidae Viruses - None Bacteria Aeromonas liquefaciens (Syn. Pseudonlonas flouresceilli Chondrococcus columnaris Fungi Saprolegnia Achlya ::!h hydrophila, A. punctata). Table 16 (Cont'd). Cyprinidae Viruses - None Bacteria Aeromonas ligllefaciens (Syn. :A. hydrophila, A. punctata) Pseudomonas flllorescens ChondrococcllS columnaris Fungi Saprolegnia Achlya Esocidae Viruses - None Bacteria Aeromonas liqllefaciens (Syn. : A. hydrophila, A. punctata) Pseudomonas flllorescens Chondrococcus coillmnaris Fungi Saprolegnia Achlya Brachiomyces Ictaluridae Viruses Channel catfish virus (has not been found in reservoirs) Bacteria Aeromonas liquefaciens (Syn. : A. hydrophila, Pseudomonas flllorescens Chondrococcus collllnnaris !2.. ~unctata) Fungi Saprolegnia Achlya * Information from Dr. John A. Plumb, Auburn University Department of Fisheries and Allied Aquacultures. 80 Company in 1958. Following that kill this mill installed additional waste treatment facilities that improved the quality of its effluent to meet current water quality standards for the state of Alabama. This has resulted generally in fair water quality downstream to the vicinity of Marathon Southern Corporation (mile 172). However, under some adverse conditions, Marathon Southern Corporation has has to instigate additional effluent treatment to prevent their discharge from degrading the Tombigbee River to a level less than the water quality standards set by the Alabama Water Improvement Commission. While the current condition is satisfactory for fish sm"vival and growth, an effert should be made to improve the general water quality throughout the upper two-thirds of Coffeeville Lake. 5-H. Establishment of Coffeeville Lake fishery including flooding schedule. The orig'in of the freshwater fishery in Coffeeville Lake was the fish populatiOll inhabiting the Tombigbee River and its tributaries between Demopolis Dam and the site of Coffeeville Dam at the time Coffeeville Dam was closed. As the lake began to flood the banks and tributary flood plains, it provided an enriched habitat for the expanded production of fish and fish-food organisms. This additional food supply resulted in an increased reproductive and growth rate for most species of fish. This fish population continued to expand throughout the filling period and for some time after the reservoir reached elevation 32.5 feet ms1. 81 5-1. History of species composition, relative abundance, and condition within each species including methods used to obtain fish samples. One of the major problems that has confronted fisheries biologists has been the lack of techniques to accurately estimate the population of fish that exist in large impoundments. To date, the estimates that are available in various publications and in biologists' files are open to criticism, but no one can say that they are unreliable. In large ponds and small lakes it is usually possible to get an accurate COlillt of the population by draining the water from the basin, collecting all of the fish, and separating, measuring, counting, and weighing each species present. While this destroys the fish population it does allow an accurate count and weight of the fish present at the moment they were collected. In large impoUl1dments on a river this technique is impossible and tillwarranted for many reasons. 5 - I-1. Methods of sampling fish populations. In the search for techniques that would prOVide reliable estimates of the fish population in a large impotilldment, a munber of methods for collecting fish samples have been employed, Some of the more commonly used methods are seining, netting (gill, trammel, and hoop), trapping aJaskets and boxes), trawling (a relatively new technique for freshwaters), poisoning (rotenone and antimyacin), and electrofishing, Coupled with the use of each of these methods, some investigators have collected, marked, released, and then recaptUl'ed fish in an attempt to estimate the standing crop of fish in an area by establishing ratios between marked and unmarked fish captured by one of these sampling methods, 82 5-1-1-a. Rotenone sampling. The most popular technique employed in recent years has been area sampling by use of rotenone. This method employs the use of a block net, which sholild have a mesh no larger than 3/8 - inch, be of sufficient depth to reach from the surface to the lowest point on the bottom around the perimeter of the sample area, and e of sufficient length to completely sLU'round or block an area of 2 or more acres, This net is very carefully set arolmd the sampl.e area several hours prior to the aetual appl.lcation of the rotenone. It is common practice to set the block net at night since there is less disturbance of fishes within the area and possibly more fish are in the shallow water areas during darlmess, Care must be taken in setting the net to have the lead-line in contact with the bottom at all points arOlmg the sample area. It is also helpful to leave this net in place for at least a day after rotenoning or lmtil the bloated fish are all recovered to prevent their floating all over the lake. To determine the quantity of rotenone required to collect fish, the volume of water within the block net is determined. The quantity of rotenone to apply is at least sufficient to give a concentration of 0,05 ppm rotenone for the entire volLune of water within the area. After the quantity of rotenone needed is measured it is mL'{ed with several volumes of water, and the mb.ture is pumped down a perforated hose to produce a lmiform concentration from surface to bottom throughout the sample area. The usual application pattern is to block all four sides with a wall of rotenone and then make diagonal crosses from corner to corner. Sufficient potassium permanganate (2 pounds of KMn04 for each pound of 5 percent rotenone compound used) should be on hand to start neutralizing the rote83 none in waters outside the block net a few minutes after the fish begin to surface in the sample area. Care should be taken to apply the KMn04 a sufficient distance from the net to prevent undue chemical damage to the rope and webbing. For best results in recovering fish, sampling with rotenone should be done when the water temperatlU'e within the area to be sampled is no lower than 75 degrees. The higher the water temperature when rotenone is applied the faster fish will react, also those fish which sink to the bottom when killed will bloat and float much quicker allowing greater total recovery as well as more accurate weights and measurements. It is also imperative that an adequate crew equipped with sufficient boats, nets, and containers be on hand when sampling starts, and that the crew remains available for the second day pickup. A11 pickup crewmen should be made aware to pick up all fish seen whatever species or size it might be. In addition to the water operation of this population sampling, there must be an adequate sorting, measuring, and weighing crew equipped with accurate measuring boards or sorting tables, with sufficient inch-group containers for holding sorted fish, and accurate scales for weighing the various inch-groups of each species. Accurate identification of species, and accurate records of numbers and weights of each inch-group of each species must be stressed. If this method is used to sample a fish population, and great care is taken to collect all fish from within the net area, and to record accurately all weights and numbers of each inch-group of each species, then a reliable estimate of the fish population within this type habitat in the reservoir may be obtained. 84 When selecting sites for rotenone sampling of fish populations it is important that the specific areas chosen be representative of as large an area of comparable habitat in the lake as possible. Rotenone sampling can be effective in water depths to 20 feet, but at greater depths the dispersion of toxicants is very difficult. Also it must be remembered that the block net must reach from the surface to the bottom of the sample area. This restricts the depth of water also within the selected area. Likewise, stumps and snags must be minimal to allow setting of the block net and also to allow free movement of fish collecting crews throughout the sample area. 5-1-1-b. Electrofishing. Electrofishing devices are currently being used in sampling techniques that count or collect game, forage, or rough species of fish in shallow water areas of rivers and impoundments. If such equip- ment is properly operated, and the biologists are careful in their capture and data taking techniques, this fish sampling method results in practically no mortality to the fish populatIon. This makes electrofishing advantageous over the rotenone method so far as public relations are concerned. The electrofishing gear consists of a 110 volt, 60 cycle AC generator with at least 3,000 watt output, a control panel with variable AC or DC voltage outputs, a heavy duty 2-pole foot-operated switch, and an electrode system that can be arranged in various configurations to produce the desired electrical field. The specific electrode configuration used to sample the fish populations in Corps lakes is a rectangle, i. e. a terminal electrode was located on the outermost end of each of the 2 booms some 12 feet in front of the boat and another electrode was located on each 85 of these booms some 6 feet behind the outermost ones. The width between the tips of the booms was approximately 10 feet. This electrofislung equipment was mounted on a wide beam, square bow, 16foot alumimun boat powered by a 25 h. p. outboard motor. The bow section of this boat was covered with a square deck and fitted with a 3-foot high guard rail. When operating, the electrodes were adjusted to be suspended about 5 feet into the water. With the power supply operating the unit was adjusted to produce a load of approximately 800 watts within the electrode field. Two types of sampling of the fish population were accomplished by this electrofishing operation. The biologist on the bow of the boat was equipped with a dip net wlule the boat operator was eqUipped with a tape recorder. As the fish surfaced in the electrical field they were identified, counted, and recorded on tape. Selected sizes of all species that were affected by the electrical current were collected for age-growth determinations, and condition of the ovaries was examined in samples collected during spawning season. 5-1-2. Fish population studies (Rotenone). There were three pre-impound- mentand one post-impoundment (through 1973) rotenone samples collected from the Coffeeville Lake area. The pre-impoundment data were collected above old Lock 1 in 1955-57. This information is presented in Table 17. It is included in this plan to give some idea of the fish population that originally existed in this stretch of the Tombigbee River. These river population data were summarized by methods proposed by Swingle (1950) to describe the relationships and dynamics of balanced and unbalanced fish 86 Table 17. Fish population data collected by rotenone sampling in Coffeeville Lake in 1955-1957. Spcclus i\bovc Lock J Below loci, 8/2/5fi 8/1/57 \\'t. Ib5. E AT Wt. Ibs. l ;\'1' W1. Ib.... l .1. !J 1,0 WhHe crappIe 0.2 0.01 Blnc\. crappie 4.46 o.n 0.5 0,2 While bass 1.9 0•• 100 salt",a10l' striped bass 1.6 0.5 100 Walleye 1.0 o.a 50 bass 7 J." !ja.9 5.% J.!) Rooster Bridge Hoosler Ol'iclg-c 7/20/56 8/5/65 8/2/57 8/'2/57 :\1' L:u'g"()ll1outh bass ~))otlod 2 .\!lo\'e Lock 2 1 Above I.ock 2 ~ %.5 \\'t. Ibs. E t\T 0.' 0.2 100 G.G 1,3 6j. !) 2. :I 0.5 0.6 \\'t. ItJs. O. 75 E :\r 0.2 5:l "'" 62.8 Wal'rnoulh 0.0'2 - 0.0 0.0 Spolled sunfish Ol'angcspollCd sunfish Longclll'sllUfish BlueJ.:"11i .26 .0. 0.0 !ted-oar Arncric:'tll eel E AT D.!>2 0.5 80 0.02 0.0 0.0 2.04 1.1 \,0 0.04 0.0 n.D o.oa 0.0 il. 0 0.05 0.0 0.0 0.0 100 Southet'll rockbllss 00 \\'t, Ius. 0.01 0.0 0.0 .68 0.1 0.0 0.22 O. I 0.0 0.0:1 0.0 0.0 0,08 0.2 0 0,4·\ 2,2 43.0 3.25 1.0 70.8 .J. 8 1.1 62.:- H.G 1.7 2.13 1.2 7k O.G O. I "'0 D.G:; D. :1 07 0.5G 0.1 0 59. I 99 [i~.{j7 29.2 '" '" 11.·1 D.l(j .03 0.0 - O.G 79.5 JO.!! :l.!i 99. I l. 85 IJ:lddlcflsh \.0 o 'J !J2 0.2 Dlue catfish !)g.8 :13. :l 80.0 236.8 ·\G.2 75.3 58.9 18.n (iJ. 5 13·1. 0 30.9 82.0 Chanllel calfish 51.0 J 7.2 ·1:3, 0 ·16.9 !J.2 78..\ 2~.8 9. (j :J3.G ,18. I 11.1 47. 8 25. ·11:1 (j.5 -18 54.7'] 30. :l .1. 3 J. ,I 97.7 :H.2 (j.7 9:1.0 46. S IS.O 9:1.4 28.0 G.·I 8G. 7 2:).12 5.8 100 0.27 0.2 U. :;'1 0.0 0.0 T 0.0 0.0 0.02 0.0 0.0 0.18 O. I 0.0 D.UG 0.0 0.0 Flalhead calfish l\1:ldlOll1s illoollCYC Alab~lrnn ~hntl L5 0.5 0.0 - 2:12.7 0.0 Table 17, cont'd. l\bove Lock I Uclo\\' Lock 2 "I Above Lock 2 B/2/fiG S/1/57 8/2/57 wt, Ius. I': SI,ipjnck herring G.7 2.3 Thl'cadfin shad 1.8 o.n 10.7 a. G Species Glzznt'd shad Wt. lb,'1. E !l0.9 0.78 0.2 64.1 0.0 0,27 0.1 I.G 0.02 kl' 100 BaY:llIchovy fl'cshwatcr drum GG.S 22.5 Small1110uth buffalo 23.2 7.8 7:1.8 100 8.2 AT e \Vt. Ius. e 0.0 0.7 o -, 100 0.0 0.0-1 0.0 100 :.l.a 0.4 90.0 0.15 0.0 0.0 I. 12 O•. J 8. ~j 0.7 0.1 D.:! 98.1 I U. 97 5. -, 85.9 17. :1 -\. 0 1).1." J2.9 0.0 0.0 158.4 :;0.9 8G.O '12. G 81. -I 185.9 42.8 89.·\ 7:1. Ii, ;] \,2 1:12. !J '\T II. !I 100 ." 100 2.2 0.5 Wt. Ius. E: 100 2.7 1.5 18.7 00 55.'1 :10.7 80 :J.O II J. 07 D.G Ion 5. <I :\.1 100 0.5 O. :1 0.0 0.19 1.1 0.0 T 0.0 0.0 T 0.0 0.0 T 0.0 0.0 1\'1' GO. (j I.O!) 0.:1 0.0-' O. I 100 T T i\Ioscluitofish 0.0 0.0 0.0 T 0.0 T Fundulus sp. 0.07 0.0 0.0 0.01 0.0 0.0 0.0 0.0 0.0 0.0 0.89 0.2 0.0 Banded PYb'lny sun(jsh - Plrale pClL'ch Oat'lers (Perc! Il3 sp. ) 0.0 0.0 Spotted gar I\Ll:mlic needleush AT 0.0 Longnosc gar 00 00 ~ll Urld~c a/5/(;5 7/20/56 1.2 Wt. Ibs. ll.oos1cI' Hooster Sridg:c 8!:<V57 F. 0.8 2·1.-1 I\bo\'o Lock 2 Wt. Ib,<;. AT Qulllbnc]( I-li);;hfln carp sucker ~~ T 0.0 0.0 T 0.0 0.0 - 0.01 0.0 0.0 U.:W 0.1 0.0 2.07 O. (j 0.0 O.li5 0.2 0.0 0.33 0.2 0.0 Shlne!"s (Notropis sp.) 1.6 0.0 0.0 4. !) 1.0 0.0 Chubs (Hvbopsis sp.) 0.8 0.0 0.0 T 0.0 0.0 T 0.0 0.0 0.05 0.0 n.o 0.82 o' n.o o. JG O. I 0.0 l'imoph:l1os sp. 0.02 0.0 0.0 0.1:\ 0.0 0.0 .03 0.0 0.0 .02 0.0 0.0 0.:.3 0.0 0.0 0.07 0.0 0.0 0.02 0.0 0.0 .02 0.0 0.0 T 0.0 0.0 SilVel"Y minnow Unidentified minnoll's T TOT,\ L Ilarveslable fish 0.::; Ibs llnrvcstable fish 0.25 Ibs S:11l1plc includes all "Carpiodes sp." 0.0 0.0 populations. A brief summary describing the meaning of terms used in this methodology of data evaluation are given below. Balanced populations are defined as "those capable of producing satisfactory annual crops of harvestable fish. They were characterized by haVing (1) a definite range in ratio of the weights of forage and piscivorous species, (2) a narrow range in the ratios of weights of small forage fishes to the weights of piscivorous groups, and (3) more than 33 percent of the total population weight in the form of fishes of harvestable size". The "c" class is composed of species that feed principally upon other fish and cannot attain normal adult life without such food. The" F" class is composed of all other species present in the population that feed principally upon plants, plankton, insects, and other small aquatic invertebrates. The "c" value is the weight in pounds of "C" class species and the "F" value is the weight in pounds of the "F" class species. The ranges in F/c ratios in balanced fish populations was from 1. 4 to 10. O. Populations with F Ic ratios from 1. 4 to 2.0 were overcrowded with "c" species. Balanced populations with F/c raticE below 3 were inefficient due to the overcrowding of "C" species. Tllis condition was found to reduce the total weight of the population. The F/c ratio was a relatively stable value (in ponds), remaining almost constant despite variations in rates of fishing for" F" and "C" species. This ratio is useful in comparing and determining the condition of fish populations. The "Y" value in a population is the total weight in pounds of all fishes in the "F" class which are small enough to be readily gulped by the average-size adult 89 in the "C" class. The Y/C ratio is an expression of the food available to the "C" class. The most desirable populations were in the range Y/C ~ 1. 0 to 3.0. The "AT" value is the percentage of total weight of a population composed of fish of a harvestable size. In balanced ponds the range was from 33 to 90. The most desirable populations had values between AT ~ 60 to 85. The "E" value of a species is the percentage of weight of a population composed of that species. The "1"" class and also "1"" species were subdivided into groups of "large," i. e. fishes of harvestable size; "intermediate," those too large to be eaten by the "C" species and too small for harvest; and "small," the fishes small enough to be eaten by the average-sized individual in the "large" group of "C" species in the population. The "A 1"" value is the percentage of the total weight of the "1"" class composed of large fish. The "IF" and "SF" values are percentages of the total weight of the "1"" class composed respectively of the "intermediate" and "small" fishes. An "A 1"" ~ 35 appeared to be the minimum value found in desirable populations and apparently expressed the maximum allowable depletion of the adult "1"" species if satisfactory production is to be maintained. the range "A F " ~ 60 to 80. The most desirable populations were in Satisfactory populations occurred in the "SF" value range from 15 to 40. The "A 1"", "IF'" and "SF" values were fOlmd to be dynamic values shifting with changes due to harvest, predation and natural mortality. Pond studies indicated that harvest of adult" 1"" species increased the pounds of "C" species per acre and that failure to harvest the former group resulted in a decrease in the pounds of "C" species in the population. 90 Separation of various species into the various classes specified in the population analyses outlined above are g"iven in Tahle 18. 5-1-3. Fish population studies (Electrofishing) 1974. The data obtained by electrofishing in Coffeeville Lake during the summer of 1974 are summarized as the numbers of each species of fish sighted-per-minute of shocking (Tables 19 and 20), and as the relative condition (K n ) of the various species of fish collected (Figures 6 and 7). In 1955-57 (see Table 17), catfish made up approximately 57 percent of the total weight of fish sampled, with freshwater drum accOlUlting for another 32 percent, bass, bream and crappie amounting to 3 percent, and threadfin and gizzard shad accounting for 3 percent. The presence of such a low poundage of shad within this population in- dicates that slack water did not exist within the area sampled. The information in Tables 19 and 20 on the electrofishing surveys in Coffeeville Lake during 1974 reflects the fish population of the water habItats that were created by Coffeeville Lock and Dam. These data indicated that the inundated tributaries support the major population of game fish in Coffeeville Lake. It is evident that these two sampling techniques, which were carried out at different times and places, sampled two distinctly different fish habitats. From information which is currently available it can be concluded that a major portion of the original fish population may still exist in this 96.5-mile stretch of the Tombigbee River. 5-1-4. Comparisons of relative conditions (Kn ). It has been suggested that average length-weight relationships of major species of freshwater fishes be prepared for large geographic regions, and that these averages be used as a base 91 Table 18 . Lengths (in inches) used to classify fish of different species as young, intermediate, or harvestable, and as forage, carnivorous or other. * Species co '" Young Fish Paddlefish 0-12" 0- 8" Spotted gar Longnose gar 0-12" Shortnose gar 0- 8" Gizzard shad 1- 5" Mooneyc 1- 6" Goldfish 1- 6" Carp 1- 8" Carpsuckers 1- 8" Northern hog sucker 1- 7" Smallmouth buffalo 1- 8" Bigmouth buffalo 1- 8" Black bu [falo 1- 8" Shorthead reclhorse 1- 7" River reclhorse 1- 7" Golden redhorse 1- 7" 1- 5" Blue catfish Channel catfish 1- 5" Flath ead catfish 1- 5" 1- 6" White bass Intermediate Fish Harvestable Fish Forage Fish 13-31" 9-19" 13-19" 9-19" > 32" l! 20" ::? 20" ~ 20" <? 6" <? 12" <?.11" <? 13" ::>. 13" <? II" ~ 13" ~ 13" ~ 13" <?11" ?11" ~ 11" ?10" ?10" ? 12" ~ 9" 0-12" 0- 8" 0- 8" 0- 8" 0- 8" 0- 8" 0- 8" 0- 8" 0- 8" 0- 8" 0- 8" 0- 8" 0- 8" 0-10" 0-10" 0-10" 0- 6" 7-11" 7-10" 9-12" 9-12" 8-10" 9-12" 9-12" 9-12" 8-10" 8-10" 8-10" 6- 9" 6- 9" 6-11" 7- 8" Carnivorous Fish - Other Fish > 12" All Sizes A11 Sizes All Sizes > 8" - - - > 8" > 8 11 > 8" > Sit > 8" > 8" > 8" - > 8" > 8 11 - > 8" - > 8" > 10" > 10" > 10" > 6" Table 18, ""'" Species Young Fish Warmouth Bluegill Spotted bass Largemouth bass White crappie Black crappie Saugcr Freshwater drum Miscellaneous Small Fish 1- 3" 1- 3" 1- 4" 1- 4" 1- 3" 1- 3" 1- 8" 1- 5" All Sizes * From "An Intermediate Fish 4- 5" 4- 5" 5- 8" 5- 9" 4- 7" 4- 7" 9-11" 6- 8" - (Cont1d). Harvestable Fish > 6" 2'.. 6 1t ~ 9" ~10" > 8" ;:: 8" ~12" :;;::, 9 t1 - Forage Fish Carnivaraus Fish 0- 5" > 0- 5" 0- 4" 0- 4" 0- 6" 0- 6" 0- 6" 0- 6" All Sizes Other Fish 5" > 5" > 4 11 > 4 11 6" > 6" > 6" > - Evaluation of Cove Sampling of Fish Populations in Douglas Heservoir, Tennessee" in Reservoir Fishery Resources Symposium, 1967. > 6" Table 19. Results of electrofishing at selected sites on Coffeeville Lake, 1974. Group Total Sights of various groups of fish Average sights-per-minute of various groups of fish 31 .34 9 .10 Bluegill 13 .14 Redear 11 .12 Sunfish 2 .02 Pickerel 1 .01 Warmouth 2 .02 Blacktail redhorse 2 .02 Carp 1 .01 Carps ucker 4 .04 Spotted sucker 1 .01 Freshwater drum 1 .01 Golden shiner 1 .01 Fundulus 4 .04 20 .22 103 1.11 Bass White crappie Gizzard shad Total 94 Table 20. Results of electrofishing at selected sites on the Tombigbee River below Coffeeville Dam. Group Total sigbts of various groups of fish Average sights-per-minute of various groups of fis h 2 .022 Bluegill 10 .111 Crappie 1 .011 Channel catfish 5 .055 Flathead catfish 2 .022 Mullet 4 .044 Shiner 4 .044 Carpsucker 4 .044 Longnose gar 3 .033 Freshwater drum 2 .022 Carp 1 .011 Bowfin 1 .011 NeedlEfish 1 .011 Shad 21 .233 Total 61 .677 Bass 95 Largemouth bass 1.5 I 1.4 White crappie I 1.3 I 1.2 I 1.1 I I ,L ~ 1.0 .8 I I .7 I .9 I I .6 .5 Bream " I 20 25 30 35 . 40 . 45 • 10 I 15 ----------.----. - - T - - 20 25 r -- - , 10 15 20 I 25 Total Length (mm x 10) Figure 6. Distributionof Kn factor for various sizes of three groups of fish collected from Coffeeville Lake in 1974. Kn Bass 1.6 Bream - I 1.5 ~ 1.4 - 1.3 - I I 1.2 - I 1.1 - I -0 1.0 .9 - I .8 - I .7 - .6 - .5 I I I I I II I I I I . I I I , , , , 10 15 20 15 20 25 30 35 40 45 50 Total Length (mm x 10) Distribution of Kn factor for various sizes of three groups of fish collected from the 'fombigbee River at Jackson, Alabama in 1974. 30 Figure 7. II Catfish 35 40 45 5 for the determination of the relative condition factor Kn . Such a set of average length- weight relationships for many species of fishes from rivers, lakes, and reservoirs in Alabama are available (W. E. Swingle and E. W. Shell, 1971), and these averages were used to determine the Kn values of all major species of fishes collected from Coffeeville Lake. The data for 1974 are presented in chart form in Figure 7. In these data, a Kn value less than 1. 0 indicates poor condition, a value of 1. 0 indicates average condition, and a value greater than 1. 0 indicates good condition. The Kn data for Coffeeville Lake are limited, but are believed to be unbiased representative (electrofishing) samples of the species present in this lake. The data inlicate that the general condition of the game fish sampled ranges from poor to average within each species. In the case of basses, whose main diet is smaller fish, there was a tendency toward equal distribution of individuals in poor to good condition regardless of their total length. average condition. Crappie, on the other hand, were all less than In the bream (sunfishes), whose chief diet is immature aquatic insects and other macroinvertebrate forms, there was a tendency toward more individuals in poor condition than in average or good condition. As pointed out earlier in this plan, Coffeeville Lake is considered a run-of-theriver impoundment, and as such has a limited shallow water area that is conducive to the production of the types of food that bream will consume. Thus, the limited num- bers of bream sighted and captured is a reflection of the lack of suitable habitat to produce their food supply. The largemouth and spotted basses and crappie depend upon smaller fishes for their diet, and in Coffeeville Lake their main food supply is gizzard and threadfin shad. 98 Again, it is stressed that this is a limited quantity of data, but they were collected from some of the more productive stretches of the lake. A notable omission in these electrofishing data is the lack of information on commercial fish species. 5-J. Fishing pressure. No reliable estimates are available on the number of fishermen, or the nmnbers of fish that were caught, for Coffeeville Lake. Since such information is normally obtained by creel census studies, the proposal for obtaining such information on Coffeeville Lake will be presented in that discussion. 5-K. Creel census data. A creel census is in reality a method of bookkeeping designed to determine the nmnbers and pounds of various species of fish harvested by various methods and the effort (time and manpower) to obtain this harvest. The survey can be more sophisticated and determine the age and sex of fishermen, the point of origin of the fishermen, and other facts if so desired. Inherent in the design of the census is the fact that daily and day-of-week fishing preSSLU'e, as well as monthly fishing pressure, can be readily eA1;racted from the data. However, the most important information is to secure as accurate and complete record as possible of the nunlbers and weights of each species of fish harvested from the entire body of water and the time required to attain this harvest. On a reservoir the size and shape of Coffeeville Lake, and with so many private entrances, it becomes an almost impossible task to devise a reliable creel census plan. If such a plan could be devised, the cost would be excessive based upon the total area of this lake. While the catch per fisherman trip and the total fishing 99 pressure as well as the total catch for Coffeeville Lake would be desirable, it is not recommended for immediate implementation as a part of this Management Plan. 100 6. MANAGEMENT OF THE FISHERY. The management plan presented in this section is one that, for the cost involved, has the greatest potential for increasing fishing success in Coffeeville Lake. It must be emphasized that if post-operational evaluation indicates a particular part of the plan does not provide the desired increase in fish production, this phase should be discontinued and a different approach devised. AIso, in those cases where no economical management plan can be devised, it will be recommended that the operational procedure remain at its present status. 6-A. Reservoir fishery biology. This section is a brief review of some basic biological processes of a reservoir fishery that were considered in evaluating the fishery condition in Coffeeville Lake, and in the preparation of the Management Plan that will follow. The two principal problems involved in fish production are (1) the production of an abundant supply of fish food, and (2) the management of the fishery for a high sustained yield of harvestable sized fish. An analysis of any reservoir fish population is a complex problem involving an understanding of the habitat, the food supply, the biology of each species of fish, the relaticnships that result from all of these species living together, and the impact of removal upon a sustained harvestable population. Information on the types of habitats, and the potentials for fish-food production have already been discussed in previous sections of this plan. In summary, it can be stated that a large portion of the bottom in Coffeeville Lake is too deep to be utilized for macroinvertebrate (fish-food organ·sms) production. In too large a portion of its Sh'l low water (less than 8 feet deep) area the exposed bottom material 101 is silt that shifts with current and wave action. On the other hand, the inflow of nutrients is more than adequate, but water movement is too e,,1:ensive to permit the development of heavy densities of phytoplankton in this lake. There was no evidence, from any recent studies, that water quality was inadequate to support an abundance of all forms of aquatic life. Since Coffeeville Lake is located upon a large stream that receives a great deal of organic as well as inorganic waste products, a diversity of food sources is available which requires fishes of different feeding habits to fully utilize these resources. The species listed in Table 13 indicates that an adequate diversity of feeder types exists in tllis lake and tailwaters. The presence of such scavengers as gars, carp, catfish, and bowfins indicates the probability of a decreased rate of development of eutrophic conditions in this lake. Present eutrophic conditions are much less than would occur if these scavenger species were not present. Likewise, the presence of a moderate number of planktonivorous shads indicates adequate utilization of plankton and the production of an abundant forage group to support the population of carnivorous basses, crappies, and catfishes. It has already been pointed out that the inadequacy of suitable bottom conditions in this lake has decreased the macroinvertebrate production that has resulted in a relatively small standing crop of all sunfishes. 6-A-1. Factors affecting fish reproduction. The continued existence of all fish species in Coffeeville Lake depends upon their ability to spawn in this habitat. There are many factors that affect the reproductive success of reservoir fishes. Some of these factors are discussed below. 102 6-A-l-a. Adequacy of spawning area. The type of spawner, i. e. nest builder or random, will determine whether or not adequate spawning areas exist in the habitat. In the case of nest builders, spawning sites are located on firm bottom materials consisting of gravel, clay, or silt. Sandy bottom areas are largely unsuited for spawning since these may be shifting bottom areas. Nest builders also have a preference of water depth in which to locate their nest. depth generally ranges from less than 1 foot to approximately 10 feet. This Random spawners require shallow water areas where an abundance of egg-attachment materials (brush, grasses, and weeds) exist. 6-A-l-b. Water fluctuation. Drawdowns during spawning may destroy a few or all nests or eggs of random spawners. Rising water prior to spawning can dilute the repressive factor and induce basses, carp and buffalo to produce heavier spawns. 6-A-l-c. Water temperature. The 6-inch water depth temperatures at which various species spawn are shown in Table 21. The spawning success of early spawners such as crappies and basses may be adversely affected by unusual water temperature fluctuations. 6-A-l-d. Silt-laden waters. Waters heavily laden with silt are favorable for spawning of sunfishes and basses. Ull- Sunfishes in general are more tolerant to silt than are basses, while bullhead catfish apparently suffer no ill effects from silt. Random spawners, such as shads, carp, pickerel, and buffalo, 103 Table 21, Reproductive characteristics of various species of fresh-water fish. Species Txpe Spawner Largemouth bass nest builder singular Smallmouth bass neat builder Min. Sp3\\'lling Size, in. , T\'pc Egg No. Spawn Fry Per Year Schooling Min. Hatching Temperature. ~. sinking arihcsh'e 8-10 sinking 1 + 70 + 70 + 5' adhesive White bass nest builder 10 sinking adhesive Eastern pickerel random 15 seml-buoynnt Sauger random 12 adhesive 43 Black crappie colony or single nest wilder 7 sinking 68 White crappie colony or single ncsl builder 7 sinking adhesive Bluegill colony 3 sinking adhesive neal builder Redenr 55-GO 1 68 2-3 80 3 75 2-3 71 adhesive colony ncst bu ilder 3 colony nest builder 3 Round flier nest builder 3 heav1' adhesh'c 60-65 Warmouth nest builder 3 adhesive 80 GrCL'll sunfish colony Ilest builder 3 adhesivo 3 68-70 Longcnr colony nest builder 3 adhesive 2 71-73 Channel catfish nest builder 10.5 heavy adhesive Speckled bullhead nest builder 9 adhesive Golden shiner random 5 adhesivo Dufralo random 15 Gizzard shad rnndom 5 adhcEivo 3 + G8 Threadfio shad random 3 adllcsive 3 + 70 Redbreast sinking adhesh'c sinking adhesive 74 3 + 80 + 68 60 sinking 104 whose eggs may be attached to twigs, leaves of grasses, etc., are less susceptible to silt damage than are the bottom spawners. An often overlooked but potential siltation hazard is produced by wind-driven currents that cause suspension of shallow water silts and clays. 6-A-1-e. Repressive factor. This is a self-inflicted type of birth control first observed in goldfish, carp, and buffalo populations. Basses and sunfishes are thought to secrete a repressive factor which limits the extent of their own reproduction. 6-A-1-f. of fish will not spawn. given in Table 21. Size of brood fish. There is a size below which each species The minimum sizes of spawning fish of various species are Sunfishes that are growing rapidly may spawn at a smaller size than slower growing individuals. 6-A-1-g. Food availability during period of eg'g formation. Availability of food during the period of egg formation and maturation within the female fish will influence the number of young fish produced per female. Thus, heavy repro- duction of a species indicates rapid growth of brood fish; light reproduction, slow growth; and no reproduction, no growth or even loss of weight by brood fish. Some species such as sunfishes and shads can mature eggs within a few weeks and spawn two or more times during a summer. Other species such as basses, pickerels, carp, catfishes, and buffalo require several months for egg formation. 105 Thus, in these latter species reproductive success is influenced by conditions that existed during- fall, winter, and early spring-. 6-A-l-h. Crowding. Since crowding- results in less food per individ- ual, it results in smaller sized brood fish and slower g-rowth. Crowding may result from too many individuals of the same species and/or of competing species. The result of overcrowding- is reduced or no reproduction. 6-A-l-i. Egg-eating habit. Under conditions of crowding, sunfishes have been fOlmd to eat eggs of their own and other species. ""hen confined to sunfishes and competing and undesirable species, this may be considered a beneficial type of birth control. However, when it is extended and includes the eating of bass eggs, it is extremely detrimental for it causes unbalanced populations. 6-A-l-j. Reproductive success of prey upon which predators feed after reaching fingerling stage. Since some predatory species require fish as prey to produce normal growth, it is necessary that successful prey species reproduction has occurred. 6-A-l-k. strength of predation upon young predator species. The young predatory species are not exempt from the same predation that exists for the yOlmg of other species. Among bass, the greatest predation probably occurs when large individuals of a school start feeding on their own brothers and sisters or on the yOlmg from a neighboring nest. Since young bass largely eliminate their own nest mates, the operation of bass nursery ponds on reservoirs is of dubious value. 106 6-A-2. Predator - prey relationships. The rate and efficiency of predation within a fish population are dependent upon a number of biological and physical factors. Notable among the biological factors are the schooling habits of the various fish species. Largemouth bass fry, for example, are vulnerable to all larger bass and crappie. Since fry move about in a large school for several days after leaving the nest they are easy prey and most bass fry are eaten by larger fish before the school breaks up. Carp eggs, fry, and fingerlings appear to be e,,"tremely vulnerable to bass predation. This species cannot be classified as a true schooling species, but the fry and young fingerlings seem to congregate into groups which make them easy prey for predators. Small shad also congregate into schools arolmd which predators generally lurk. When most sunfish fry leave the nest they disperse more or less at random into shallow water areas. A chief factor in the survival of large numbers of these species is the quantity of available cover in which these small fish can hide from predators. Filamentous algae and rooted aquatic weeds, if present in sufficient quantities in shallow edges, provide excellent hiding places for many small fishes. Thus, weed control is an essential factor in establishing a healthy predator-prey relationship in a reservoir". The predatory species ("C" class) have been described as those piscivors which consume any fish they can capture that is small enough to be swallowed at a gulp. This suggests that a relationship exists between the size of the predator and its prey. By research it was established that the mouth width measurement 107 of the predator species is equivalent to the mfL'{imum depth of body measurement of the forage species that it can swallow. Since mouth width and mfL'{imum depth of body are related to total length of body, this relationship is generally expres sed as the total length of e forage species a bass of a given total length can swallow, and is given in Table 22. This chart indicates that largemouth bass can start on a fish diet at a very early age. These relationships on mouth width of predators to depth of body of forage species have been established for largemouth, smallmouth, and spotted basses, and eastern pickerel as predators, and for bluegills, red-ear, goldfish, golden shiner, and gizzard shad as forage species. If is believed that the same type relationship exists between mouth widths of crappies and catfishes and sizes of forage fish they can gulp, but to date these have not been determined. The presence of an adequate number of predators (piscivorous species) within a fish population is essential if the forage species are to be thinned to the extent that a sustained maximum harvestable crop of fish is to be produced. The chief predators for reservoirs in this area include the basses, the larger catfish, the pickerel, and to a limited extent the crappies. UnfortLmately, out knowledge of the activities of the larger catfishes is much more limited than it is for the other three species. Since the species dynamics of any reservoir fish population is dependent upon the predatorprey (Fie ratio) relationship, a discussion presented by SWingle and Swingle, (1967) concerning problems encolmtered with largemouth bass and crappie predation is summarized below. 108 Table 22. Ma-'l:imum sizes of forage fishes largemouth bass of a given inch-group can swallow. Bass Total length of forage fish Total Length InchGroup mm .... 0 '"' 1 .2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 38 64 89 114 140 165 191 216 241 267 292 318 343 368 394 419 445 470 495 521 546 572 597 Bass 111111 24 34 44 54 68 82 96 120 132 145 158 169 183 196 229 249 263 278 292 298 342 355 369 Bluegill m111 36 40 45 52 58 65 73 81 89 97 104 113 121 129 145 157 169 185 193 208 223 - Redeal' 111m 26 32 37 46 54 62 72 81 91 100 108 119 129 139 159 173 188 202 - - Green sunfish 111m 36 41 46 54 61 69 78 87 94 104 113 122 131 141 159 172 186 199 212 229 - Golden shiner mm 45 52 60 72 82 93 106 119 132 145 156 170 183 197 224 243 262 281 301 - Goldfish mm 40 45 50 58 65 72 81 89 98 106 114 124 133 142 159 172 185 198 - - Gizz",-rd s11ad 111m Thread fin Shad mm 39 45 52 62 72 81 93 104 115 126 136 149 160 172 195 212 230 246 263 284 305 327 28 36 43 56 69 79 91 102 117 130 140 155 170 Largemouth bass are efficient predators upon small fishes and are the most highly prized of the sport fishes taken from reservoirs throughout the South. This species spawns in shallow water in the spring and the young fry migrate into shallow water and feed upon zooplankton, for which they must compete with all other small fish in the same enviromnent. From the size of I-inch on, they may feed upon mix- htres of zooplankton, insects, and small fish depending upon their relative availability. Examination of rotenone samples indicate that growth of largemouth bass was relatively slow during its first summer, and that there may be from 0 to more than 100 individuals per acre in various impoundments. Since these small bass remain largely in marginal waters it is the relative abundance of small fishes in these areas that regulates their growth and affects survival. Small gizzard shad are seldom found ablmdantly in these areas making the bass principally dependent upon fry and small fingerlings of mi1l1lows and the periodically spawning sunfishes during their first growing season. By the time they are sufficiently large to migrate toward deeper waters, few gizzard shad-of-the-year are small enough to serve them as food. Those sltrviving" over-winter are able to feed upon newly hatched shad by following schools over pelagic areas only at the expense of exposing themselves to greater dangers of predation by large predators. If the shad species is gizzard shad by mid-summer to late summer again few are small enough to serve as food for the I-year bass. In both ponds and large reservoirs, the presence of gizzard shad as the principal forage fish results in two groups of bass: (1) the young O-to-II-year groups which must grow slowly, with correspondingly high losses from predation and other types of natural mortality; and (2) the rapidly-growing bass which have become large 110 enough to follow schools of shad over pelagic areas. These latter bass have mouth widths large enough to allow them to feed year-round upon larger shad. Unforttmately, no adequate detailed studies have been made in impoundments upon the food-chains of small bass and factors affecting their growth and survival to larger inch-groups. Until more is Imown of the importance of many of the sup- posedly minor species to bass growth and survival, it is impossible to develop plans for improving conditions and removing one of the bottlenecks in converting a reasonable percentage of the shad crop into bass. The two species of crappies appear to present similar problems in ponds and large reservoirs. Their principal characteristic is the cyclic nature of their abundance. A strong year-class recurs periodically, at intervals of every 3 to 5 years. gJ.'owill\·. Age groups I and II of a strong year-class are typically crowded and slow During this period, few young-of-the-year crappies survive, or there may be no reproduction. This is not because of the size of the crappie, as even well-fed 2-ounce crappie are capable of spawning, but is due to crowding within the species. Crowding may prevent egg formation or the fry-eating habits may prevent survival of a year-class. As the strong year-class passes from I to III or IV, gradual reduction in mUll- bel'S from fishing and natural mortality results in gradual increase in size, and heavy reproduction again occurs. Investigations in ponds have indicated that tendencies to periodic overcrowding were due to the fact that crappie normally spawn earlier (68 0 F) than, or approxi- 111 mately at the same time as largemouth bass, which typically spawn at 70 0 F. Young crappie after hatching, spend a few days or weeks in shallow waters and then migrate into deeper waters. Early spawning by crappie and migration into deep waters combine to make young-of-the-year bass poor predators upon O-age crappie. In bluegill-bass-crappie ponds, it is the many age class I bass that are the principal predators upon O-class crappies. These basses are the gauntlet through which the O-age crappies must successfully pass to establish a strong I age-class. quently, Conse- it was found in ponds that despite heavy crappie reproduction, a cyclic pattern of crappie ablmdance did not occur in populations in years where strong I age-class bass occurred. strong I age-class of crappie developed the subsequent year after there was heavy reproduction by crappie during a year when few or no I age-class bass were present. Larger bass apparently preferred larger sized fishes and allowed survival of too many small crappie. Once the strong I age-class of crappie developed, numbers of yOllllg-of-the-year bass declined, probably because of predation by crappie on bass fry. In state-owned public fishing lakes, once this cycle started, it was repeated within 4 to 5 years. It was always evident from seining samples taken in June when another cycle was starting. This was evidenced by averages of 10 to 30 or more crappie fingerlings per 15-foot seine haul, with no age I bass taken by the 50-foot seine and very few caught by the fishermen. In balanced populations, it is of interest that low numbers of age I bass follow principally years with abnormally high milllbers of age I bass. 112 Seining records on experimental ponds have demonstrated that in such years older bass reproduced, but age I bass allowed very few or none to survive beyond the schooling stage. Unforttmately, the rotenone samples taken in large impoundments were useless in studying this yOlmg' bass-crappie problem. Most rotenone samples were taken from July to September and by this time practically all sizes of crappie had migrated to deeper waters. If rotenone samples were taken also during the spawning period of crappie, while most were in shallow water, a more useful census would result. Possibly periodic seining during spring to mid-sunmler would provide a census of the O-class and its survival. Trapping, creel census, and relative condition data can yield information on frequency and length of cycles. Crappies are not undesirable species in either ponds or large reservoirs; biologists just do not yet have technique s for their management . 6-B. R~sume' of factors affecting fish production in reservoirs. 1. The latitude and altitude of both the drainage area and the reservoir determine the temperature of the lake water and the species of fish it may support. 2. The shape, size, and geographic location of its drainage area determine in large part the quantity of waters flowing into a reservoir. 3. The type of soil, and its management, on the drainage area determines the sediment load borne by inflowing waters. -~ 113 4. The types of soils and agTicultural practices employed on the watershed determine the natural nutrient concentrations in inflowing waters. 5. The quantities of domestic and industrial effluents released into tributaries to the reservoir augment the flow of nutrients into the reservoir environment. 6. The inflow - storage - output ratios of nutrients in a reservoir determine the trophic levels that are mainta ined. 7. The storage of nutrients in bottom soils of reservoirs is dependent upon water depth, flooding, and level of release of discharge waters. 8. The conversion of nutrients into phytoplankton will retard development of macrophytes in shallow water areas of reservoirs, whereas the conversion of nutrients into macrophytes will inhibit the development of phytoplankton in a reservoir. 9. The presence of macrophytes will act as precipitators of silt resulting in more rapid clearing of water, but this process may result in elimination of shallow marginal areas in the reservoir. 10. The maximum food production in a reservoir is attained when a moderate quantity of the available nutrients are converted into phytoplankton. Conversion of nutrients into large amOlmts of phytoplankton produce unfavorable habitat conditions. 114 11. The type of bottom in the euphotic zone of a reservoir may determine in large measure the percentage of phytoplankton converted into macroinvertebrates that serve as food for fish. 12. The presence of other substrate materials, such as brush and rooted aquatic plants, increase attachment sites for macro invertebrate production. 13. To efficiently utilize all forms of food available within a reservoir, the population of fish must include species whose feeding habits are adapted to utilize these varied food sources. 14. The population of fish within the reservoir is composed of those species present within the impOlUlded portion of the stream at the time the dam was closed. If other species are considered desirable or necessary in the reservoir fish population they should have been stocked when the dam was closed and allowed to expand with the native fish. 15. There must be an adequacy of spawning areas in the reservoir to provide for annual recruitment to the fish population. 16. A predator-prey relationship must be established and maintained that is capable of reducing the total numbers of fishes to a level of maximum sustained harvestable-sized sport and commercial species. 115 17. An excessive quantity of macrophytes can provide too much protection for small fishes from predators and result in an over-crowded and stlmted fish population. 18. There must be an adequate annual harvest by fishermen to remove a high percentage of the harvestable-sized sport and commercial species. This will permit adequate reproduction and the maximum rate of growth among; the recruitments to the population. 19. An abundance of large, trophy-sized bass or other species taxes the available food supply and results in a decreased total standing crop and fewer harvestable sized fish. 20. Inadequate removal of harvestable-sized fish results in an abundance of older individuals that are more susceptible to parasite and disease attacks. 21. Parasite and disease infections are higher among species with schooling habits. Also, incidences of infection are greater during spawning periods when many individuals are crowded into smaller areas than at other periods of the year and antibody production is at its lowest leveL 6-C. Information VB. action. It is evident from the preceeding discussions that all prior data gathered on Coffeeville Lake may be classified as information, and practically no use has been made of this information for either the promotion 116 or management of the fishery for a greater sustained yield of harvestable sized fishes. The time has long since passed for utilization of the available information on water quality, aquatic weed control, and fish population data that applies to Coffeeville Lake, and to collect the needed data to completely evaluate and manage this fishery. The most pressing need for information at present is a reliable estimate of the quantities (numbers and weights) of both sport and commercial species of fishes harvested by fishermen from this lake. This information can only be obtained by an organized creel census conducted for a sufficient period (at least 2 years) to provide reliable information. It is suggested that when such a creel censLls is conducted that it be in accordance with the procedLUoes described by the Southern Division of American Fisheries Society. 6-C-1. Public relations. This phase of the Fishery Management Plan might be considered as the equivalent of customer service in a large corporation. Its purpose is to provide fishermen with such information as the kinds and habits of fish inhabiting Coffeeville Lake; the most successful method to employ to catch these fish; the (current) areas where fishing for various species has been most sLlccessful; bottom contoLUo maps to indicate depth to fish; and weekly dissolved oxygen concentration and temperature profiles for the lake. Tills information on fishery biology is an integral part of the training of any fisheries biologist. The dissemination of this information to civic groups, conser- 117 vation and wildlife groups, and school children could be most helpful to the public to better understand problems of fish production as well as in their harvest of fish. These presentations could be timely and include fishing teclmiques for those species currently being harvested. The information on current "hot fishing holes" could be disseminated weekly along with water temperature and dissolved oxygen concentration data. This type information could be displayed on bottom contour maps along with the best depth at which to place the bait. 6-C-2. Fishing access. The various points of access for boat fishermen on Coffeeville Lake are presently adequate to allow most areas to be within a 20 to 30 minute run from a concrete ramp. In a limited number of places one may have to drive many miles and cross the lake to reach an access point. It is felt that the present number of points for boat fishermen are sufficient for present fishing pressure. A few ramps need to be widened to premit two vehicles to be launching or retrieving boats at the same time to better accommodate the occasional large crowds. Bank fishermen, on the other hand, have had no special facility consideration to date. They have simply had to be content witb existing bank conditions regardless of their proximity to favorable fishing grolmds. it is suggested that this aspect of reservoir fishing could be improved in limited area by construction of fishing piers or dikes into favorable shallow water areas. Such structures might lend themselves as barriers that would permit the fertilization or baiting of embayments for special groups such as handicapped or lmderprivileged children. 118 In the tailwater areas immediately below Coffeeville Dam the construction of a fishing walkway on the west bank would permit a greater number of people a safer access to this fast water fishing area. Such a walkway could be usod in that area which is currently closed to boat fishing by a chained buoy line. This is a minor cost item that could greatly increase tailwater fishing access from a relatively safe platform. 6-C-3. Fishing intensity. It was stated in the introduction that the pri- mary purpose of tllis fishery management plan was to prOVide the greatest sustained yield of harvestable sized fish based upon its basic fertility. Attaining this yield requires a sustained fishing preSSLU"e particularly dLU"ing those periods when certain species are in the shallow water areas or are on their beds. The publicity of this information is one approach to acquiring intense fishing pressure. However, to sustain this fishing pressure requires that a majority of these fishermen catch fish. 6-C-4. Creel limits. It is contended that the present high creel limits are a factcr that determines the relative fishing success of a majority of fishermen. It is well known that the consistent fisherman knows where and when to fish, and when he locates a bed or area where fish have congregated that he will remove one or more full limits on several consecutive days. This procedure does remove large numbers of fish, but it does not prOVide catches for the vast majority of fishermen. A lowering of limits would tend to promote a greater spread of catches to more fishermen. Tllis should result in a greater stimulus to a wider fishing clientele which should be the philosophy for any public waters that are operated from general public funds. 119 The harvest of adequate numbers of commercial species, especially the catfishes and carp, from Coffeeville Lake has been rather sporadic and in a large sense restricted. Unfortunately, no data are available on harvest of either commercial or game species to indicate how adequately the present fish crop is being utilized, but it is suspected that less than 50 percent of the annual crop of all catchable groups is being harvested. Since it requires approximately as much food to maintain a pound of fish as is required to produce a pound of fish, the harvest of commercial species should be encouraged to release some of the pressure upon the food supply of game species. By proper selection of fishing gear, the probability of catching game fish by commercial techniques is considerably lessened. However, if our assumptions on game fish harvest are reliable, then the removal of a limited number of game species by commercial gear could only result in an improvement of the entire fish population. 6-C-5. Evaluation of fishery management changes. The operation of a concurrent creel census on game and commercial fishing would be the only way to accurately evaluate most of these proposed changes in regulations as regards their influence upon the total fish harvest of Coffeeville Lake. However, as pointed out earlie.' in this Plan, current implementation of a creel census on Coffeeville Lake is not recommended since it would be very costly to operate. 6-C-6. Fishing tournaments and rodeos. Another factor in adequately harvesting the game fish population of this lake to sustain a maximum harvestable crop is the operation of bass tournaments and fishing rodeos. As mentioned pre- 120 viously it requires about the same amolmt of fish food to maintain a pound of fish as it takes to produce a pound of fish. For example, it requires about 4 pounds of fish to produce a pound of bass within one year. It will require an additional 4 pOlUlds of fish to maintain this one pOlUld of bass through its second year of life, plus 4 more pOlUlds of fish if it gains another pound in weight. Thus by the time a fish is 2 years old and weighs 2 pounds he will hawe consumed 12 pounds of fish (enough food to have grown three one-pound bass in one year). If a bass lives to be 6 years old and weighs 6 pOlmds at the end of that period, it will have consumed more than 80 POlUlds of fish during that period (enough to have produced 20 onepound bass during these six years). Fisheries management technology has not advanced to such a stage that it can provide means to produce these greater numbers of smaller bass in preference to the one larger fish in larger impoundments, and it is not known that if such a technique were available if it would result in a balanced fish population in such impoundments. These facts were pointed out to indicate that the removal of trophy-sized basses by tournaments and rodeos can have a beneficial effect upon a reservoir's overall fish population in the release of pressure upon the available food supply. This results in a brief stimulation of growth among basses and possibly crappies. In any impoundment inhabited by gizzard shad, it is necessary that the population of basses consists of individuals of all sizes from yOlU1g-of-the-year to old grandads. As mentioned earlier, larger basses seemingly prefer near maximLUll sized forage fishes that they are capable of swallowing; thus these "lunker-sized" basses are a necessity to control the numbers of gizzard shad and other forage fishes. 121 Their occasional removal only allows a slig-htly smaller bass a more abundant food supply and an oportunity to reach the "lunker" category. Tournaments and rodeos have thus far only encouraged the growing-up of smaller basses. 1f tournament activity is too extensive (in size and frequency) it could eventually result in a gradual decrease in sizes of larger basses, but it is doubtful that this point has been approached in thls lake. Thus, from the fish manager's standpoint, a limited nllln- ber of moderate-sized tournaments and rodeos would be considered a desirable means of harvesting a segment of the fish population that is taxing- the available food supply. 122 7. Coordination with Other Agencies The establislunent of a fishery habitat by the impoundment of Coffeeville Lake created a problem of managing this public resource.. By custom, it has been assumed that the fishes living in this body of water belong to the state until they are caught and removed at which time they become the property of the fishermen. States have been resistant to assume the management of these federally financed projects on the grounds that no State revenues are derived from such installations whereas private utilities do pay taxes on their impoundment holdings. There is no likelihood that this attitude wi II change in the immediate future. States do ins ist however, that the fishery created by these federal impoundments is still their responsibility. This Plan assures the State of the continued role as principal participant iu the management of fisheries within its jurisdiction. 7-A. Personnel and funding. In light of the above sltuation, it must be assumed that the Corps of Engineers has a responsibility to the public, who financed these projects, to provide the financial means for their management. The procedures for solving all management problems are details beyond the scope of this Plan. However, it is felt that the Plan can include some suggested methods for their initial enactment. The Corps of Engineers should employ a skeleton staff of professional fisheries management personnel to act as liaison between themselves and the State fisheries biologists. These Biologists should be provided with adequate li.lllding· for each reservoir under their jurisdiction to provide for collection of essential data and conduction of public relation and other managerial aspects of each reservoir's fishery. 123 Warrior Lake, Holt Lake, Demopolis Lake, Coffeeville Lake, and Okatibbee Lake could all share a fisheries biologist who would coordinate the fisheries management activities of the Corps of Engineers and the state of Alabama. Various parts of the fisheries program then could be contracted to the Fisheries Divisions of the Alabama Department of Conservation and Natural Resources, to state universities or conducted in-house. Such an arrangement should be designed to encourage state participation in the plan, and in-house implemention would be used as a last resort. The role of state universities in this management plan would be restricted to research activities in relation to specific biological or management problems. The fisheries biologist should be adequately trained in fisheries biology and management and have an M. S. degree. The suggested rating would be a G. S. 9 or 11 in order to attract qualified persons. The flIDding provided by the Corps of Engi- neers for implementation and continuing the management plan of vVarrior Lake could be based upon fisherman usage estimates, and could be as high as $0.05 per fisherman visit. This figure would provide adequate monies to conduct a good creel census and to start some of the other activities set forth in this plan if the Corps and state biologists deem a creel census is needed. 7-B. Cost-benefit projections. It is impossible to place a value upon the benefit derived by an individual for one fisherman visit to Coffeeville Lake. Cer- tainly the value would be several times the $0.05 cost per fisherman visit indicated above. In addition, for each fisherman visit, it is estimated that he placed into the local economy (spent) well in excess of $1. 00 to make this visit. Thus, the cost- benefit ratio could conceivably range from 1: 25 to more than 1: 1, 000. 124 Equipment for biologist. 7-C. The fishery management biologist must be provided with certain specialized equipment if he is to be efficient and effective in providing technical assistance that will result in a higher sustained yield of fish on the stringer. The following items are basic to this biologist being self-sufficient over the wide territory that he must keep under continuous surveillancl". L Pickup truck equipped with a lockable body cover. 2. 16' fiberglass boat (Boston Whaler type). 3. 65 or 85 h. p. outboard motor with at least an 18 gallon gas tank. 4. Heavy duty boat trailer. 5. Corps communication radios in both truck and boat. 6. state communication radio in truck. 7. Water sampling equipment to include: a. Dissolved oxygen-temperature meter with at least 50-foot lead or probe. b. Water sampling bottle capable of collecting water sample at any depth. 8. 9. c. Ice chest with quart size Nalgene plastic sample bottles. d. Secchi disc. Fish sampling equipment including a. 25' x 4' one-fourth inch mesh seine. b. Dip net with one-fourth inch mesh bag. c. Ice chest with plastic sample bags. 35 mm camera. a. Color film for slides b. Black and white film for news releases. 125 7-D. Job description - Fisheries Management Biologist. The qualifications and duties listed below are minimum requirements for a Corps of Engineers Fisheries Management Biologist. Degree: M. S. in Fisheries Management. Training to include: 1. Warm-water fisheries biology. 2. Management of large impoundment warm-water fisheries. 3. Fish disease and parasites. 4. Water quality in relation to fish production. 5. Aquatic plant identification and control. 6. Fish identification. 7. Statistics. 8. Public speaking. 9. Journalism. Duties: 1. Thorough knowledge of the fishery habitats within each Lake for which he is responsible. 2. Knowledge of the sm'rounding drainage area, especially the sources of domestic, industrial, and agricultural pollution. 3. Knowledge of current sport fishing success on each lake including most productive areas. Share information with public through news releases, radio, T. V. and Lake bulletins. 4. Knowledge of commercial fishing on each lake including number of fishermen, type of gear used, and kinds and amounts of fish harvested. 126 5. Maintain surveillance for fish kills and determine cause(s). Report to appropriate state agency. 6. Current knowledge (at all times) of water quality conditions throughout each lake. Share information with public through news releases, radio, T. V., and posted information on lake. 7. Maintain surveillance on aquatic plant (including phytoplankton) populations and determine when and where control measures should be employed. 8. Cooperate with state fisheries biologists on all above-mentioned duties so that both may better inform the public about the fishery within each lake. 9. Promote fishing interest through news releases, public appearances at clubs and civic groups, and by personal contacts on lakes. 10. Identify, help develop, coordinate and participate (to be informed) in any contractural management or research plan that may be in effect on each lake. 11. Actively participate in local, state, and regional fisheries organizations to inform and be informed on current management practices. 12. Coordinate and encourage participation of each Resource Manager and other Corps personnel on each lake project in collecting and dis seminating information relative to that lake's fishery. Note - This biologist could be most effective if he did not have citation authority. In this way he can contact persons with valuable information, but who are noncommunicative with law enforcement personnel. 127 7-E. Budget. The personnel required to implement this Fisheries Management Plan consists of a District Fisheries Biologist and a Project Fisheries Biologist. This Project Fisheries Biologist would be shared by Coffeeville Lake (20 percent), Demopolis Lake (30 percent), Warrior Lake (20 percent), Holt Lake (20 percent), and Okatibbee Lake (10 percent). The work basis for Coffeeville Lake will be as follows: Project Fisheries Biologist, GS-9, 20 percent, 52 days Estimated annual cost is as follows: a. Personnel Fisheries Biologist (GS-9) ($13, 791 + 32%) x .20 $ 3,641 Contingencies (15 percent) 546 Supervision and Administration (15 percent) 546 b. Equipment ($12,500 x .04*) 500 c. Operating expenses 1,200 Subtotal d. 6,433 Management Practices Fishing piers, creel census, weed control, population studies, etc. Total Cost (268,000 x $0.0613 per user day) Total Benefits (268,000 x $1. 00 per user day) *Equipment costs prorated over 5 year period. **Due to limited use by fishermen the cost per fisherman visit is greater than amount suggested in body of Plan. 128 10,000 16,433 268,000 8. Research Needs for River and Impoundment Management. Improved techniques for evaluating the present and future fish populations in rivers and impoundments are urgently needed by State and Federal regulatory agencies and by industries that are required to biologically monitor the effects of their wastes. Equally important, we need to utilize, at the optimum level, the productive capacity of our natural surface waters. Title: Improvement and Evaluation of Fish Sampling Techniques for Use on Rivers and Impoundments. Situation: One of the major problems confronting management of fisheries in rivers and impolmdments is the inadequacy of available techniques to sample all facets of the resident fish population. This is a distinct handicap to fisheries biologists who are attempting to improve sport and commercial fish production. Equally important is the fact that it is virtually impossible for biologists to evaluate either detrimental or beneficial effects of waste or heated-water effluents upon fim production in rivers and impoundments. Objective: 1. To devise a sampling system that provides total recovery of the standing crop of fishes in a given area. 2. To develop new sampling techniques that will permit the attainment of the first objective. 129 3. To evaluate the efficiency of individual sampling techniques to estimate a portion or all of the standing crop under various types of habitats. Title: Factors Affecting Food Chain Development in Rivers and Impoundments. Situation: The availability of food is the chief factor involved in fish production in rivers and impoundments. Since the majority of fish foods are produced within an aquatic environment, their degree of abundance is not nearly so obvious as it is with terrestrial forms. In addition, the characteristics of the aquatic habitats are not so obvious as they generally are on land. Most life history studies of aquatic forms have been conducted singly and little effort has been devoted to integrated food chain production studies. Thus, the various factors which may have the greatest influence upon the food chain for various species of game and commercial fish are little known or understood. Only through a better understanding of food chain relationships can fish production in many waters be managed or improved. Objective: 1. To devise sampling techniques capable of collecting representative forms of all major food groups for fresh water fishes. 2. To more fully understand the general life-cycle of each group of organisms that are components of the food chain for fish. 3. To identify the physical and chemical factors that are beneficial and harmfUl to all component organisms in the food chain. 130 4. Evaluate the gain or loss in efficiency of conversion for food chains of varying complexity. Title: Optimum Nutrient Loading for Maximum Fish Production in Rivers and Impoundments. Situation: Plant nutrients, mainly N, P, and C, are generally the limiting factors in the production of adequate food to attain the maximum natural production of fish in rivers and impoundments. Several other chemical and physical factors seemingly influence the quantity of plant nutrient necessary for optimum fish production in a given aquatic habitat. Experience in farm fish ponds has shown that the combination of factors are almost as variable as the number of ponds that have been studied, but there appeared to be average values for the components of the combinations that tend to optimize fish production. It is believed that similar sets of combinations exist to optimize fish production in rivers and impOlmdments. Objective: L Correlate rate of nutrient flow with the standing ()rop of fish in rivers and impoundments. 2. Compare fish production in impoundments resulting from agricultural and non-agricultural nutrient sources. Title: Optimum Harvest Rate for Various Trophic Levels in Rivers and Impolmdments. 131 Situation: It has been shown in pond research that individuals comprising a fish population do not grow unless a sufficient UlU1mer of the larger individuals are harvested and the pressure on the food supply relieved to allow smaller individuals to attain harvestable size. This rate of harvest was found to be proportional to the available food supply. In rivers and impolmdments the rates of harvest of sport and commercial species are generally unknown. The same can be stated concerning the trophic levels of these same environments. The LU'gent need is to accumulate sufficient information to correlate optimum harvest rates with nutrient input of the various streams and impoundments throughout the Southeast. Objective: 1. To determine the optimum rate of harvest of fish from rivers and impolmdments with different rates of nutrient flow. 132 9. Synopsis CoffEeville Lake, with a surface area of 8,500 acres, a length of 96. 5 miles on the Tombigbee River, an average depth of 23 feet, and a drainage area of 19,000 square miles, is a run-of-the-river navigation impoundment which at normal pool elevation of 32.5 feet msl was retained largely within the banks of the river and tributary stream channels. The Lake is subject to excessive flood waters one or more times each winter and spring. unregulated Tombigbee watershed. The major flooding often results from the The degree of turbidity associated with these flood waters is dependent upon the severity of the flood producing storms. The quality of inflowing waters into Coffeeville Lake at Demopolis Dam have recovered sufficiently from upstream pollution to meet Alabama's standards so far as dissolved oxygen concentrations are concerned. The extreme variations in flow tint have previously been experienced at Demopolis Dam are partially alleviated by stream flow regulation affected by Lewis Smith Dam. FLU·ther regulation will be possible once the Tennessee-Tombigbee Waterway structures on the Upper Tombigbee River are completed. At Tombigbee River mile 205.2, the Gulf state Paper Company plant has, in the past, released excessive paper making wastes into the river. This has resulted in one or more rather extensive fish kills. Tllis waste is currently collected, held, and treated to such an extent that it meets Alabama's water quality requirements. Further downsh'eam, at river mile 171. 8, American Can Company operates a.paper mill that currently releases adequately treated waste into the river. 133 Prior problems with this waste and fish lulls has been partially caused by poor quality water coming from Gulf States upstream. It is still desirable that each of these mills give more adequate treatment to their effluents to eliminate these sources as potential fish-kill agents. Due to the steep and continuously agitated (by barge wakes and stream flow) sandy banks along the river chmmel, there is no growth of marginal aquatic plants, except in immdated tributary areas. embayments is alligatorweed. The most prevalent plant in these tributary Its spread is not anticipated to expand since a good population of Argentine flea beetles is present to exert biological control. Other less noxious aquatic weeds present in these embayments include lizard tail, Sagittaria, American lotus, giant cutgrass, and cattails. There is little likeli- hood that submersed weeds will ever become established in these areas since these waters stay turbid much of the winter and spring each year. The fish population in Coffeeville Lake consists of those species present in the Tombigbee River at the time Coffeeville Lock and Dam was closed. Since its closure the floodwaters have overflowed the dam sufficiently to allow fish free passage up- and down-stream. From observations and discussions with persons Imowledgeable of sport fishing activity on Coffeeville Lake, it can only be assumed that fishing pressure is only moderate on this Lake. The accessibility, for boat fishermen, appears adequate in the productive sport fishing areas. provided for their use. The bank fishermen have had no special facilities It is recommended that fishing pier s or earthen embanl<ments be constructed at favorable locations to accommodate this segment of the fishing population. 134 Limited commercial fishing is still practiced on the river proper, but the composition of this catch is unknown. Data on availability of sport fish indicate that moderate populations utilize the inundated embayments in the lower reach of the lake. The bass, which depend upon shad and small sunfish as food are in fair condition. in poor condition. Crappie were generally This occurred because their food, which i<; small shad, is limited. The majority of the Lake bottom, except in flooded embayments, is lillsuited (because of shifting sand:;) for fish-food organism production. Thus the sunfishes were few in mLmbers and we::e from poor to fair in condition. This condition status of the fish population in Coffeevill,e Lake is a direct result of a poor physical habitat fOJ" fish-food production. The Fisheries Section of the Alabama Deaprtment of Conservation and Natl.~r'll Resources ClLrrently has no manag'ement plan in effect on tllis impoundment. do check bass reproduction on the lake each year. They The employment of a fisheries biologist (to be shared jointly between Coffeeville, Demopolis, Warrior, Holt, and Okatibbee Lakes) by the Corps of Engineers would provide a liason between the Corps and the State. Any future management of this fishery would be jointly approved by biologists from each agency. The actLtal fisheries management would be conducted by the State, and the Corps would provide contractural funds for their fair share of any program that was initiated. 135 References Cited Swingle, H. S. 1950. Relationships and dynamics of balanced and unbalanced fish populations. Auburn Univ. Agri. Expt. Sta. Bull. 274. Swingle, H. S. 1953. 74 pp. Fish populations in Alabama rivers and impoundments. Trans. Am. Fish. Soc. 83 :47 -57. Swingle, H. S., and W. E. SWingle. 1968. populations in reservoirs. Problems in dynamics of fish Reservoir Fish. Resources sym. 11. 229-243. Swingle, W. E., and Eo W. Shell. 1971. Tables for computing relative conditions of some common freshwater fishes. Circular 183. 55 pp. 136 Auburn Univ. Agri. Expt. Sta. This Plan has been submitted to the Fisheries Di vision, Alabama Department of Conservation and Natural Resources for review and comments. After review, ali comments from the State of Alabama were favorable and agreed with the management needs for this Lake as set forth in this Plan. Particn iar interest was ex- pressed by the State on the establishment of fishing piers. NOTES