TPWD 1962 F-2-R-9 #778: Fisheries Investigations and Surveys of the Waters of Region 2-B: Fisheries Reconnaissance

“\i J03 COMPLETION REPORT .As required by FEDERAL AID 1N FISHERIES RESTORATION ACT Texas Federal Aid Project No. F-Z—R’9 FISHERIES INVESTIGATIONS AND SURVEYB 9F THE WATERS 0F REGION 2-B Job No. 3-22 Fisheries Reconnaissance Project Leader: John G. Wood H. D. Dpdgen Executive Secretary Texas Game and Fish Commission Austin, Texas Marion Toole Eugene A. Walker D-J Coordinator Director, Program Planning April 4, 1962 ’5‘ u : ~ .. 0".“- ABSTRACT . . An effort was made to determine the extent of a fish kill which occurred on the Colorado River during January 1961a Counts of dead fish along selected stretches of the 200 river miles affected, plus seining collections, were made for this purpose. A near total kill was indicated for the first 50 miles of polluted stream. Routine netting trips were made to Lake Travis, Marble Falls Lake, and Lake Granite Shoals on the Highland Chain of the Colorado River, and to Lake Belton, where routine physical and ecological notes were madeo These investigations reveal no major fish population changes, except that in Lake Travis there is evidence indicating a sharp reduction in blue catfish since 1954. Marble Falls Lake continues to provide poor largemouth bass fishing. In Lake Granite Shoals, Myriophyllum _p. continues to interfere with boating and fishing activities. A lake drawdown in January 1962 may relieve the problem dur- ing the coming segment. There has been a recent reduction in commercial facilities at Lake Belton, concur- rent with poor white crappie fishing. JOB COMPLETION REPORT State of Texas Project No. F-2—R-9 Name: Fisheries Investigations and Surveys of the Waters of Region 2-B. Job No. 8—22 Title: Fisheries Reconnaissance Period Covered: February 1, 1961 - January 31, 1962 Objectives; To conduct limited investigations to obtain current information concerning gross changes in fishing conditions and factors influencing fish populations. Procedure: Fish populations of selected waters were sampled principally by the use of small—mesh experimental gill nets. These nets consist of five 25~foot sections ranging between one and three inch square mesh. Mesh size increases by oneuhalf inch per section. Random net sets were used in all cases. An effort was made to note ecological conditions which might affect the fisheries complex. Turbi4 dity, siltation, aquatic vegetation, land use in the surrounding terrain, and pollution indicators were routinely observed. Field samples were cempiled and analyzed to determine major changes in population ratios'or relative abundance of species as well as general condition. These data will be used in planning future survey or management work in the concerned waters? A checklist of Species mentioned in this report is given in Table 1. Findings; Colorado River During February 1961 an effort was made to determine the extent of a fish kill which occurred on the Colorado River below Austin in January of that year. Details of the kill are reported in Job C-l, Fu2~R~9, 1962. Kill estimates, based on visual counts along selected stretches of the river, reached 1,000 pounds per stream mile for the initial 200 miles of the kill area. A near total kill was apparent for the first 50 miles of that dis— tance, as seining collections at selected points in the area revealed no fish life except at the mouth of a small tributary where one blackstripe topminnow, one bluegill, and a few gambusia were taken. Beyond the approximate 200-mile stretch of heavily affected riven the extent of the kill apparently diminished rapidly. The section of river concerned has since been removed from Project F-2—R boundaries, and work in this area was con- sequently abandoned. -2- Lake Travis Sixteen experimental gill nets were set in Lake Tracie, Travis and Burnet counties, on October 25-26, at the confluence of the Pedernales River with the lake. An effort was made by the project leader to inspect commercial facilities, interview fishermen, and reconnoiter the general area, as most of Lake Travis is is largely unfamiliar to current project personnel. ' Netting data for Lake Travis are presented in Table 2. A comparison was made between the collected data and that of the basic inventory (Job Bwl, F—2mR-l, 1954) since no resurvey work of consequence has been accomplished on the lake since that report. While the data is too sketchy to draw conclusions, it is noted that gizzard shad comprised 43.59 per cent of numbers and 9.78 per cent of weight during the period of the original inventory, as compared with 35.57 per cent of numbers and 16.69 per cent of weight as shown in Table 2. If these data may be compared, it appears that the change in relative abundance of shad in 22uyearmold Lake Travis has not been significant since 1954, but that average size has increased. Selected comparisons between the 1954 inventory data and data collected during this segment are indicated below: Per Cent Number Per Cent Weight Fish/100 Ft.Net Set 1954 1961 1954 1961 1954 1961 Gizzard shad 43.59 35.57 9.78 16.69 5.88 3.45 Smallmouth buffalo 1.85 6.70 6.54 17.84 0.24 0.65 River carpsucker 7.02 6.18 1 95 11.97 0.94 0.60 Channel catfish. 3.62 5.67 $.29 4.70 0.48 0.55 Blue catfish 15.76 1.55 15.01 0.86 2.12 0.15 Spotted bass 1.60 1.03 2.57 0.59 0.21 0.10 Largemouth bass 1.98 2.58 3.47 0.69 0.26 0.20 - OWWWW Comparisons were made on these Species (in the absence of other data) despite the fact that it is obvious that quantitative, seasonal, and other sampling varia» tions are great. The most striking comparison from the above is that pertaining to blue catfish, which were aimost absent from the 1961 collections. This is felt to reflect an accurate trend, since all sources (fishermen, news reports, and observations by project personnel) have indicated a steady decline in this species. Marble'Fallg‘Lake On July 20—21, ten experimental net sets were made on Lake Marble Falls, Burnet County. During the period of this brief reconnaissance, an effort was made to interview fishing camp operators and fishermen regarding angling success. As reported in earlier segments, angling success for largemouth bass appears well below the norm for the six lakes comprising the Highland Chain of the Colorado River. Trotlining for channel and flathead catfish remains the most popular and productive fishing method, and seasonally, white bass fishing is fair in the upper lake. -3- A sandy terrance bordering the west side of the lake for some two miles is eroding at a rapid pace and resulting siltation is serious. The shoreline along this area is receding so quickly that pecan groves whose borders were located 10 feet to 25 feet from the waters edge 3 years ago, are now rapidly disappearing into the lake. Results of the Marble Falls netting are shown in Table 3. Lake Granite Shoals Trips were made to Lake Granite Shoals, Llano and Burnet counties on August 30-31 and November 21-22, where a total of 26 experimental gill net sets were made. Results of this netting are included in Table 4. No significant variations between these and previous net collections were noted. It is felt that the nettable fish population complex remained essentially unchanged during the segment. The most serious fisheries problem existing in this lake is that of submerged aquatic vegetation, chiefly Myriophyllum.§p., which chokes most coves, tributary mouths, and inlets to the exclusion of sport fishing. vast areas of open lake are also inaccessible to fishermen because of the vegetation. Considerable money is Spent each year by fishing camp andchxflrowners for chemical control of the vege— tation around boat and fishing docks and their approaches. A lake drawdown, accomw plished during January 1962 by the Lower Colorado River Authority, may help to relieve this problem during the coming growing season. Lake Belton Netting trips were made to Lake Belton in Bell County on June 13~l4 and December 20-21 where a total of 21 experimental net sets were made. Results of these collections are shown in Table 5. At least from this limited data, no major population changes or trends are considered apparent when compared to pre— vious data for this lake. There has occurred a reduction in commercially operated facilities at Lake Belton during the past two or three years; apparently, a direct reflection of a concurrent drop—off in fishing pressure and success. Most significant has been the almost complete lack of success of white crappie fishermen during this time. White bass, while increasing in creel reports and in project survey work, have not yet reached a population concentration which will attract large numbers of Sport fishermen. Recommendations: It is recommended that this job be continued. The opportunity to make periodic visits to project waters and obtain fish samples and other data is considered vital for determining areas needful of extensive resurvey or development programs. Data used in compliance with Job B-2l (proposed harvest regulations) of this project will be gathered as a part of this work. Since Project F-2~R has been extensively -4- realigned during the past segment9 it is anticipated that considerable time will be utilized under this program during the next segment to familiarize project personnel with new waters and their fisheries problemso \ Prepared by John G; Wood Approved by ZEEM Jfl—f’é Project Leader oordinator Date: April 42 1962 ‘ -’ . ..... » Regional Supervisor -5... Table l. A Checklist of Species Mentioned in Report Common Name .SpOtted gar Longnose gar (Bizzard shad Smallmouth buffalo River carpsucker Gray redhorse sucker Carp Golden Shiner Channel catfish Blue catfish Flathead catfish Blackstripe topminnow Common mosquitofish White bass Texas spOtted bass Largemouth black bass . Warmouth Green sunfish 'Redear sunfish Bluegill Longear sunfish White crappie Freshwater drumr Rio Grande cichlid WW‘W Scientific Name Lepisosteus oculatus Regisosteus osseus Dorosoma cepedianum Ictiobus bubalus Carpiodes carpio Moxostoma congestum Cyrpinus carpio Notemigonus crysoleucas Icualurus punctatus lgtaluruslfurcatus Pylodictis olivaris Fundulus notatus Gambusia affinis Roccus ghrysops Micropterus treculi Micropterus salmoides Chaenobryttus gulosus Lepomis cyanellus Lepomis_microlophus Lepomis macrochirus Lepomis megalotis Pomoxis annularis Aplodinotus grunniens Cichlasoma sxanoguttatum “W ~6~ Table 2. Lake Travis Netting Results9 1961. Longnose gar Gizzard shad Smallmouth buffalo River carpsucker Gray redhorse sucker Carp Channel catfish Blue catfish White bass Texas Spotted bass Largemouth black bass Warmouth Green sunfish Bluegill White crappie Freshwater drum Rio Grande cichlid Totals 8.25 35.57 6.70 6.18 1.54 1.03 15.98 .52 4.63 194 100.00 “Weight 63.08 33.75 36.07 24.22 .88 1.75 9.38 .38 .19 11.85 1.64 202.27 Per Cent of Weight 31.19 16.69 17.84 11.97 .44 2.99 4.70 .86 4.63 .59 .69 .18 .23 .09 5.86 .24 .81 100.00 -7- Table 3. Lake Marble Falls Netting Results9 1961. Per Cent Species Number ' of Number Longnose gar 4.25 Gizzard shad 26.95 Smallmouth buffalo 9.93 River carpsucker 11.35 Carp .71 Channel catfish 11.34 Flathead catfish .71 10.63 7.00 White bass .71 .44 .29 Warmouth 2.13 .44 .28 Green sunfish 1.42 .25 .17 Bluegill 27.66 4.44 2.92 Longear sunfish 2.84 .51 .34 Totals 141 100.00 152.04 100.00 —— Table 4. Lake Granite Shoals Netting Results. 1961. l Longear sunfish l Per Cent Fer Cent I Species Number of Weight - of Number Weight Longnose gar 3 .48 i 8.25 1.10 i Gizzard shad 179 . 28.69 44.35 5.95 I Smallmouth buffalo 104 I 16.66 ! 424.83 56.99 I River carpsucker 169 27.09 174.36 23.40 Gray redhorse sucker 3 .48 5.81 .78 Carp 1 I .17 I 3.00 .41 1 Golden Shiner 2 .32 .57 .08 l Channel catfish .25 4.00 44.04 5.91 i Flathead catfish 1 .16 2.19 .29 White bass 7 1.12 3.31 44 Texas Spotted bass 1 .17 3.06 .41 Largemouth black bass 4 .64 4.00 54 Warmouth 7 1.12 l 21 17 Green sunfish 2 .32 .32 .04 ! Redear sunfish 1 .16 J .13 .02 Bluegill 56 8.97 I 5.58 .74 1 White crappie