TPWD 1956 F-5-R-3 #242: Inventory of Species in San Angelo Reservoir, Job No. F-5-R-3

JOB COMPLETION REPORT Wit «.1 State of TEXAS Project Noe FwS—R-3 Name: Fisheries Investigations and Surve s of the waters of Region 3-Bo Job Noe B—3 - Titles. Inventory of Species in San Angelo deservoir Period Covered: May 1, 1955 - May 1, 1956 ABSTRACT lo To obtain data on the fishery populations and some of the influencing ecological conditions seventy-nine gill net collections and thirty-six seining cola lections were taken from San Angelo Reservoirs watez°analyses for dissolved carbon dioxide and oxygen content were taken periodically and more detailed chemical anew lysis data was obtained from the State Board of Water Engineerso Other recorded data included water temperature (surface and at established depths) pH, and climatic conditions at the time of each sampling of the fishery populations. A sample nnme bar of fish for each principal species were exanined and condition (K) was computedg Food habits were determined from stomach contentso Other data relevant to the study included observation for a Spawning activity and a study of the lakessproductivityo 20 San Angelo Reservoir impounded most of its storage during the first year of inventoryo The lake level fluctuated slightly until September l95ho From that time a continued decline of about 05 feet per month has occurreda 30 About 8,811 individuals of thirty species and ten families were capm tured by seining or in gill net collectionso Two species were believed to be intros duced by bait dealers or fishermen. to White bass indicated a trend toward domination over similar game speciesc Largemouth bass declined significantly) and channel catfish and white crappie had advanced to a position of being the most important game species at the end of inventoryo 5° Gizzard shad were the most important forage specieso 60 River carpsucker were apparently well established as the dominant species in the reservoir and that tendency may be increasing. Since there is no knonw utilization of this species it is concluded that these fish constitute the primary management problem for the reservoiro 70 During inventory the most severe drought ever recorded for this area occurredo At no time during the first four years following the closing of the flood control conduits has the reservoir reached the average annual minimum poolo maximum storage during the period was about the area allocated for siltationo 2. 8. It is believed that the anticipated annual fluctuations of the water level as expected under the adopted plan for reservoir management will prove suf- ficiently detrimental to prohibit the successful propagation of largemouth bass. OBJECTIVES To determine the species present and their relative abundance as well as to determine the ecological factors influencing their distribution. PROCEDURE During inventory seventy~nine gill net collections were made at 23 note ting stations in San Angelo Reservoir. Experimental nylon gill nets measuring 125 feet long by 8 feet in depth and made up in five, 25 foot sections, were used. mesh size for these nets increased progressively in each following section at onewhalf inch intervals beginning with one-inch.mesh and terminating with a threeminch mesh section. Thirty-six seining collections were made at fourteen localities along the lake shore. In nearly all collections both 26 foot %” mesh bag seines and 15 foot %” mesh common sense seines were used. To estimate relative abundance a count was made of all individuals taken in two hauls with a 26 foot %” mesh bag seine for each collection. In additional seining where relative abundance data was not taken, a four foot common sense seine with a 1/16" mesh was used. To collect fry after the spring spawning by fishes, a h foot by 8 foot straight nylon seine with 1/32" mesh was used. water analysis for dissolved carbon dioxide and oxygen content was taken' periodically and surface temperature, pH and the climatic conditions were recorded for each netting and seining collection. Significant turbidity was recorded on five occasions. To make a detailed study of the largemouth black bass population, 2,237 individuals of that species were tagged and released at eight localities in the reservoir. In net collections, most fish were identified, counted, weighed, measured and sexed in the field. A sample number of each species were examined for stomach content and a scale sample taken. On occasions it was necessary to preserve an individual, its stomach or some other organ for more detailed examination in the laboratory. When this was required, the specimen was preserved in 10% formalin. COOPERATING AGENCIES United States Corp of Engineers United States Geological Survey State Board of water Engineers Fish and Wildlife Service, River Basin Studies FIEEIHGS Description - San Angelo Reservoir is adjacent to much of the north and western residential additions of the city of San Angelo in Tom Green County, Texas. The impoundment, h0,855 feet long, of compacted impervious earth fill and reinforced concrete construction, was completed in l951~52 by the U. S. Corps of Engineers for flood control and storage of water for municipal, industrial, and irrigation uses. The dam bisects the North Concho River 6.6 miles above the confluence with the South Concho River and at that point is 128 feet above the river bed. Two concrete conduits are located at this point to provide the regulation of flood releases and in.making reservoir withdrawals. These conduits are 18 feet in diameter, #89 feet long, pass throusi the base of the dam and have a maximum discharge potential of 25,100 secondmfeet. The reservoir is primarily for flood control and has a maximum design of 691,h00 acre feet capacity; however the top of the flood control pool would contain about 391,500 acre feet and would have a mamimum.area of 12,696 surface acres. Con— servation pool is designated at 1908 feet above mean sea level, and at that level the reservoir would contain llh,300 acre feet and will have 5,hhl surface acres. “Dead Storage", that portion of the reservoir allocated for siltation, is below elevation 1886.0 and has 33,900 acre feet capacity and an area of about 2,h68 surface acres. The average annual minimum pool is estimated to be 65,613 acre feet volume and will extend to 3,h37 surface acres. Average annual maximum pool is estimated to be 97,9h9 acre feet and h,790 surface acres. Under the adopted management plan of operation the reservoir would be at conservation pool 3.5 percent of the time and no water would be retained above that elevation. All storage above "Dead Storage" and below conservation pool level, a total capacity of 80,000 acre feet, was pur- chased by the city of San Angelo for municipal and industrial consumption. Water levels are estimated to be above the average annual maximum pool elevation about 29 percent of the time and above the average annual minimum pool elevation about 7% percent of the time. Average annual fluctuation would be 8.0 feet, and maximum annual range in pool fluctuation would be about 28 feet. maximum rate of recession will be about 5.5 feet per day, and would be the result of flood releases. Probable month of’mamimum stage will be September and probable month of low stage will be January. The 1,511 square miles of contributing watershed above the dam are within the southern portion of the Congo Plains, and are characterised by strata of Chose, San Angelo, and Elaine formations of the Permian Age. Sedimentary beds of the Trinity and Fredericksburg groups of the Cretaceous Age outcrop adjacent to the reservoir area. Soils are predominately Abilene clay loans and the flood plain is composed of alluvial sandy loans, clay silts, and deposits of gravel. The most important soils in the contributing area are characterized as dark chocolatewbrown silty clay looms, calcareous, and high in organic matter. Native vegetation of the area is mixed short prairtsgrasses; however with abuse of the ranges a disclimam savannah of grasses and brush, primarily of mesquite, has resulted. Complete clim matic records for fifty-two years indicate that average annual temperature is 6t.9 degrees F., average minimum temperature in January is 32.1 degrees and average maximum temperature in August is 96.6 degrees. Average frost free period is 233 days (march 22 - November 10). Average precipitation for fiftymfive years is 21.69 inches with a maximum of t2.12 in 1882; and with minimums of 8.29 inches in 1917 and 7.4l inches in 1956. The Ecrth Concho River and its tributaries originate primarily in southern Howard county, and in central and northern Glasscock county. The stream.flows southeasterly to its confluence. The upper watershed is intermittent except for Year 1953 El. 195# El 1955 El. 1956 El. two spring areas, and where low water impoundnents provide for small storages of run-off. thimnm.recorded discharges for the river was 62,900 second-feet, and aver- age discharge over a 26.5 year period was 50.6 second—feet. Extreme low flow has been recorded for the past 19 years. Zero flow occurred about nine percent of the time, and the longest recorded continuous period of no flow, prior to inventory, was 86 days in 1931. Longest period of an apparent and significant continuous flow noted during this survey was six days. Additional information.pretaining to this stream is available in completion reports for J0bs.A-l, Ar2, B-1 and B-2. Capacities and Fluctuations - The following data pertaining to capa- cities and fluctuatuions in lake level during inventory are taken from records of the U. S. Corp of Engineers and air temperatures as recorded in the table are taken from that source. Fluctuation data and air temperatures were taken at the control tower in the dam, and were usually taken between 8 Aim. and 9 AJM. ‘Water tempera- tures were taken by commission personnel and were recorded in partat Parr's Boat Docks on the south shore of the lake, and on other occasions at Green's Concession on the north shore. water temperatures were usually recorded between 8 A.M. and 10 A.M. Capacities and Fluctuations of San Angelo Reservoir Jan» Feb march April ' may June July Aug. Sept. Oct. Nov. Dec. 1800 #6.#6 #6.70 #6.#8 51.57 51.0 70.7 69.09 71.58 83.#6 83.30 8#.82 8#.31 51 137 10# 871 73# 12391 1082# 133#6 32956. 32509 35992 3&801 1800 8#.31 83.85 83.65 83.2# 82.75 87.0 91.00 92.95 91.98 90.39 89.71 89. 33860 33181 32287 31#09 #1350 52279 5707# 5#155 52656 50527 #8607 #7384 1800 88.8# 88.61 8#.#0 87.8# 86.96 86.85 85.92 85.86 85.60 85.09 8# 51 8#.00 #6206 #5582 35010 #3529 #12#7 #0967 38639 38#92 37857 36631 35265 3#088 1800 83.65 83.#8 83.20 82.70 33181 32966 32287 31192 Symbols: El. - feet above mean sea level. AF - acre feet As shown above significant increases in the capacity of the reservoir occur— red six times during the thirty-six month inventory period. However, there was a general recession in reservoir level of about onemhalf foot per month from.July 195% to April 1956, and a corresponding decrease in capacity of about 1000 acre feet per month. Surface area reduced about 600 surface acres or about 16 percent. The most severe drought in the recorded history of this area has occurred since 1950 and this condition: had not changed at the time this report was prepared. At no time since January 1953 when dam.construction was complete and the flood gates closed, has the reservoir reached the average annual minimum.pool; nor has the expected minimum annual average discharge of the North Conche River occurred. The significance of these findings and their influence on the existing fish populations are discussed later in this report. .— Temperatures at San Angelo Reservoir WW Year 1953 1953 1953 1953 1953 1953 1953 1953 1953 1953 1953 1953 1958 1958 1958 1958 1958 195A 195A 195A 1954 1958 1958 1958 1955 1955 1955 1955 1955 1955 1955 1955 1955 1955 1955 l955 1956 1956 1956 1956 Mbnth Temperature of Surface water (F) Air Temperature (F) Mina Max. Avg. Min. Hare Avgo January #3 51 52 17 83 50 February 16 78 87 March 62 28 88 56 April 69 38 90 68 may 7h #1 106 7305 June 66 106 70°70 July 82 58 103 8005 August 78 83 80 61 105 83 September 76 80 77 53 106 7905 October 70 78 73 he 91 5715 November 66 70 68 31 78 5805 December 58 68 62 ll 73 #2 January #9 61 58 19 79 89 February 45 52 A9 27 86 5605 march 50 6O 56 26 9O 58 April 53 66 60 33 95 6h may 6h 72 68 ho 96 68 June 81 88 82 55 99 77 July 83 86 88 65 106 8505 August 84 88 86 67 102 8805 September 78 86 82 58 102 78 October 78 80 76 38 96 67 'Nevember 70 76 72 '29 58 #305 December 19 91 55 January #6 6O 55 2h 75 8905 February 118 68 57 18 76 11—7 march 55 69 6h 23 92 6795 April 72 81 100 7095 may 68 7h 72 51 100 7505 June 76 81 78 52 108 78 July' 78 83 78 65 101 83 Auguet 76 8h 77 61 103 82 September 72 78 76 52 95 7305 October 59 79 68 3h 98 68 November 59 68 62 19 87 53 December 64 68 66 20 87 5305 January 58 10 80 85 February 58 60 59 18 90 52 march 60 6h 62 22 91 56°5 April 68 78 70 36 9h 65 water Analysis — San Angelo Reservoir Year Mbnth Turbidity Air reap. (r) water Temp. (F) pH Diss. Dias. O2 002 1953 November 23 80 70 8.8 11.00 0.0 1953 December - 67 60 8.2 13.50 0.0 1958 January - 58 58 8.2 13.50 0.0 1958 February — 80 89 8.2 18.00 0.0 1958 march - 58 58 8.8 8.00 0.0 1958 April - 60 62 8.8 8.00 0.0 1958 may - 68 70 8.8 10.00 0.0 1958 June 12 76 60 8.6 7.00 5.0 1958 July 18 88 83 8.8 $7.00 2.0 1958 August - 87 85 8.8 .7.00 2.0 1958 September - 3% 78 8.8 10.00 0.0 1958 October - 75 68 8.2 13.00 0.0 1958 November — 69 58 8.2 18.00 0.0 1958 December - - - 8.2 11.00 0.0 1955 January - 55 89 8.2 15.00 0.0 1955 February - 60 82 8.3 10.00 0.0 1955 March - 63 62 8.2 11.00 0.0 1955 April 16 72 70 8.8 9.50 5.0 1955 may 18 72 69 8.8 10.00 3.0 1955 June - 86 79 8.8 12.00 0.0 1955 Ju1y - 88 83 8.2 11.00 8.0 1955 August - 88 79 8.3 13.00 2.0 1955 September - 79 77 8.2 13.00 2.0 1955 October — 67- 78 8.3 10.00 0.0 1955 November - =:- 68 8.2 16.00 0.0 1956 January - :u 58 8.3 18.00 0.0 1956 march - 69 63 8.8 11.00 0.0 Detailed data_on several other inportant aspects of water quality is not 'available for the reservoir; however records of the State Board of water Engineers and the United States Geological Survey provide some information pertaining to water quality of the North Concho River. It is considered prdbable that reservoir water is less alkaline and may also have less chloride content. Total Chlorides obtained in water analysis were from.180 to 300 p.p.mn, and hardness was from.333 to 353. As shown, no dissolved oxygen deficiencies were recorded and carbon dioxide content was not excessive. Bottom.0haracteristics — Prior to inundation 2,980 acres below elevation 1908 and located between the dam.and the limits of the recreational areas were cleared of most of the woody vegetation. Host of this clearing was done on the right bank of the river. 0n the north shore, above elevation 1886.0, most of the inundatable area was covered with mesquite and other brush species. 7. Bottom types vary from alluvium 'beach sand and terrace deposits near the inundated river bank to looms of the previously described types. An area of about 300 acres adjacent to and par- alleling the dam (where excavations were made for building materials during con- struction) is exposed caliche, and within that area a number of alkali deposits are located on the north shore near JOnes Point. Aquatic Vegetation — Excepting algae and minute pelagic forms; there is no important emergent or floating aquatic vegetation in San Angelo Reservoir. Bul- rushes occur in the river bed above the lake where gravel or silt deposits permit. Willows and.pecan are the only important woody types on the shores. 0n the felowing map twenty—one fish attractors that were constructed prior to inventory are designw ated. These structures are of second growth mesquite and are secured to the bottom with cables and stones. FISH POPULATIONS Species Distribution ~ Seining and netting collections resulted in the cap- ture of thirty species of ten families during the thirty-six month inventory period. Species and families recorded are: Checklist of Species Common Name Fanily Name Scientific Name Longnose gar Gizzard shad Smallmouth buffalo River carpsucker Gray redhorse sucker Carp Golden Shiner Goldfish* Banded Tetra* Redhorse shiner Proserpine shiner Spottail Shiner Plains minnow Parrot minnow Stoneroller Channel catfish Yellow bullhead Flathead catfish Mbsquitofish White bass Largemouth bass Warmouth bass Green sunfish Spotted sunfish Redear sunfish Yellowbelly sunfish Longear sunfish White crappie Logperch Freshwater drum * — Species introduced as bait during inventory period. Lepisosteidae Clupeidae 'fiatbstomidae '-_—'"T?_'—"'_' N Cyprinidae "-—1r——"-" H I! I“! If If H I-l fl Ameiuridag n I! Poeciliidae Serranidae Centrarchidae If H H H H I? H Percidae Sciaenidae Lepisosteus osseus Dorosoma cepedianum Ictiobus bubalus * Carpiodes carpio . Moxostoma congestum Cyprinus caflio Notemigonus crysoleucas Carassius auratus Astyanax fasciatus NotrOpis'lutrensis Notropis proserpinus Notropis venustus Hybognathus placita Pimephales vigilax Campostoma anomalum Ictalurus punctatus Ictalurus natalis Pylodictus olivaris Gambusia affinis Roccus chrys0ps Micropterus salmoides Chaenobryttus gulosus Lepomis cyanellus Lepomis punctatus Lepomis microlophus Lepomis auritus Lepomis megalotis Pomoxis annularis Porcine caprodes Aplodinotus grunniens NMO. um oconH m N on on on N K nopoopra. I on Egmmwmm 04”me Em 2H mmgoofied mmHm mo EHHHUQH .w Of the above species logperch, warmouth bass, banded tetra, and Pmoserpine minnows were taken in the river near the mouth only, and were not taken in seining collections from.the unprotectedl areas of the reservoir. Seining stations were difficult to locate and maintain, particularly on the north shore of the lake. Seining Collections: It was impossible to maintain exact seining stations because of reservoir .fluctuations.; however an.attempt was made to repeat sampling as near to a designated locality as was possible. Technique was modified somewhat by improved nylon seines during the last two year's work; however the following charts include only data obtained by sampling with bag seines. most distribution information was obtained in seining collections where population estimates were not attempted, and the following should be regarded as of importance only when considering the most important species present and their interrelationship. 113mg mammom mam wowmoono nope? 26A gammma MEG I £88m conch. powom oompobhoono I I Umom Soflwm Sousa com me .38 nonmmmooooo he 00 I 888m weapons .. z beefing Goons magnum mofiofiom I m . 3.3585 woodman...“ I H 388 figmummmm Gamma 24m . OH