(1959–1960) Report of Fisheries Investigations: Resurvey of the Waters of Region 6-B

--- Page 1 --- ELE Report of Fisheries Investigations Resurvey of the Waters of Region 6-B by John E. Tilton Project Leader Gary Wood Assistant Project Leader Dingell-Johnson Project F-2-R-7, Job B-20 February 1, 1959 - January 31, 1960 H. D. Dodgen - Executive Secretary Texas Game and Fish Commission Austin, Texas Marion Toole Kenneth C. Jurgens & William H. Brown Coordinator Assistant Coordinators --- Page 2 --- ABSTRACT A resurvey of Lake Inks, Granite Shoals, Buchanan, Belton, Marble Falls, and Austin, as well as the Brazos and San Gabriel Rivers, was carried out during 1959. Seventeen seine, 84 experimental gill net, and two rotenone collections were made on Inks Lake. The fish population was found to be similar to previous surveys, although some changes were noted in the rough fish complex. Gizzard shad showed a substantial drop in relative abundance in the netting results but rotenone samples revealed much higher population figures. Catfish and white bass dominated the game fish catch. The important largemouth bass is presumably still at a minimal population level as net and seine collections produced very few individuals. The results of 23 net sets on Lake Granite Shoals reveal very high rough fish population, but low population figures for gizzard shad. Smallmouth buffalo were the most abundant species taken, accounting for 33 percent of total numbers and 56 percent of total weight. The game fish population is con- sidered adequate and fishing remains good. The vegetation problem remains acute, but no control measures are considered economically feasible at this time. Fifty-two net sets were made on Lake Buchanan. Rough fish accounted for over 72 percent of total numbers and 78 percent of total weight. Gizzard shad made up 54 percent of total fish taken. Game fish, including channel catfish, white bass, largemouth bass and white crappie, support heavy fishing pressure on the lake. No management practices are recommended at this time. Seine collections on the Brazos River produced 5 species not taken in the original survey of the river including Notropis venustus, Notimogus crysoleucas, Ictalurus melas, Lepomis punctatus and Lepomis microlophus. Thirty-eight net sets and nine seine collections showed substantially the same fish population as had been taken in previous surveys. A limited creel census was undertaken in an effort to check the catch of white crappie from Lake Belton. The census showed 1,581 anglers fished a total of 6,872.5 hours and caught 4,944 fish, for a fish/man hour total of 0.72. The crappie were on and few fishermen utilized the in- creased bag limit on this species. Gizzard shad showed a definite decrease in relative abundance, but no reason for the decrease could be ascertained. Work on the San Gabriel River and Lakes Austin and Marble Falls was too limited for comparison with previous collections and the data gathered will be included in later reports. --- Page 3 --- Segment Completion Report State of TEXAS Project No. F-2-R-7 Name: Fisheries Investigations and Surveys of the Waters of Region 6-B. tc cae d= tcc ck dob No. B-20 Title: Resurvey of the Waters of Region 6-B. Period Covered: February 1, 1959 - January 31, 1960 OBJECTIVES To determine the present status of waters and fish populations which have been previously surveyed in Project F-2-R. PROCEDURE Fish collections were made principally through the use of standard experimental gill nets and small-mesh seines. All fish collections were taken from random locations with the exception of those from Inks Lake, which were made at stations selected in the basic survey. Seined specimens were identified, counted, and checked for sexual development in the field except for those individuals whose identification was doubtful. These were brought to the laboratory for identification. An eight-month creel census was undertaken on Lake Belton to check the crappie size and to determine if the more liberal crappie bag limit was being utilized by fishermen on the lake. The creel census required one man on each of three major fishing docks. The census began at 12 noon and ran until the majority of fishermen left the dock at night. The census started the following morning when fishermen returned to the docks and was discontinued at noon. In this way the majority of dock fishermen were contacted in the 24-hour noon to noon census period. The census was conducted on a 13-day cycle to achieve rotation in days of the week. In addition to fish collections and the creel census, physical changes which might influence fish population, were noted on the surveyed waters. OBSERVATIONS AND FINDINGS Inks Lake Netting, rotenone, and seining data were tabulated and are contained in Tables 1, 2, and 3. Data for the report was compiled from 17 seine collections, 84 gill net sets, and 2 rotenone collections during the period February 1, 1959, through --- Page 4 --- January 31, 1960. Rough fish, including longnose gar, smallmouth buffalo, river carpsucker, European carp, gizzard shad and freshwater drum, comprised slightly under 65 percent of total fish taken with the game species making up over 35 per- cent. In total weight the same rough species made up approximately 74 percent with game fish contributing 26 percent. As shown, these data are reasonably consistent with those from the 1957 and the 1958 figures. 1957 1958 1959 % No. % Wt. % No. % Wt. % No. % Wt. Rough fish 63 78 7l 71 65 7h Game fish . 37.22 29 «29 35. 35 Although the overall game fish - rough fish ratio remained fairly constant, indicated population changes in the rough fish complex were pronounced. 1958 1959 % Number % Weight % Number % Weight Gizzard shad 56.18 7.87 37.85 4.72 Smallmouth buffalo 1.90 6.97 5.89 17.56 Gar 5.29 37.83 5.43 22.68 River carpsucker 6.19 16.83 14.09 26.20 Gizzard shad continued to be the most abundant species taken from Inks Lake. Although netting figures would indicate shad make up 37 percent of the nettable fish population, rotenone samples show a much higher population. In two one-quarter surface acre test plots which were treated with liquid rotenone for total kill, gizzard shad comprised well over 50 percent of the total fish taken including cyprinids. In a selective shad kill on a seven-surface acre slough on Lake Inks the kill of gizzard shad was of such magnitude that estimates of kill were not attempted. A majority of the gizzard shad killed in the selective test were too small to be reg- ularly taken in even the l-inch mesh of the experimental nets and thus, this segment of the population does not show up in the netting figures. If the numbers of small shad present in the seven-acre test site are indicative of the lake's population it is doubtful that the predator population of Inks Lake can effectively reduce the numbers and prevent a build-up of the shad population. Netting figures continue to indicate a substantial channel catfish population and sizeable numbers of white bass. The status of the important largemouth bass population is hard to determine because of the net avoidance tendencies of this species. An effort was made to capture bass fry or fingerlings during the months of March, April, and June. Seventeen seine collections made in selected bass habitats, turned up only six fingerling bass in a total of 1,296 fish. Approximately 300,000 largemouth bass fry have been stocked in this lake since the spring of 1958. Net and seine collections as well as reports from fishermen and camp operators on Lake Inks seem to indicate a low population level for this species. --- Page 5 --- A selective kill of gizzard shad was scheduled for October of 1959. High water and the continuous threat of overflow from the lake above forced indefinite post- ponement of the job. Lake Granite Shoals Twenty-three experimental nets were set on Lake Granite Shoals during the segment period. Eleven net collections were made in the period January 26-27 and 12 collections on 27-28 of August. Although January 1959, technically is not included in this segment, the data was received too late for inclusion in the report for the previous segment. (These data are shown in Table 4). On the basis of these net collections little change can be noted when compared with previous data. Gizzard shad remain at a low level accounting for less than 14 percent of total fish taken. The smallmouth buffalo was the most abundant fish taken, accounting for over 33 percent of total numbers and over 56 percent of total weight. Channel catfish were the most numerous game fish found in this segment with white bass and white crappie also showing evidence of substantial populations. Excellent spawning habitat for largemouth bass are present in this lake and reproduction of this species is considered adequate to maintain the population. Fisher- men and camp operators reported continued fishing success for bass throughout the segment. Rough fish, including smallmouth buffalo, river carpsucker, carp, gray redhorse sucker, drum, longnose gar and shad contributed 70.59 percent of total numbers and 79.02 percent of the total weight taken from gill net collections. Despite the preponderance of rough fish, Lake Granite Shoals maintains heavy sport fishing pressure and good fishing. No drastic physical changes have occurred although continuous siltation occurs. The aguatic vegetation present, particularly Myriophyllum sp., remains a serious problem by keeping many areas of the lake virtually closed to boat traffic and hence, to fishing pressure. No extensive management practices are considered economically feasible for this iske at the present time. One two-day trip was made to each of these lakes, primarily to note physical changes which might influence fish populations or fishing pressure. Fish collections were made on each lake but the samples involve too few fish for comparison purposes and the data will be incorporated with that from future collections. No important physical changes were observed and, of course, no management measures can be recommended. --- Page 6 --- Lake Buchanan Netting data is tabulated in Table 5. Four seine collections were made and 52 nets were set on Lake Buchanan during the segment period. The seine collections produced 240 Notropis venustus and Notropis lutrensis but no other species. Netting figures are comparable with those from the 1958-55 basic survey. Rough species, including longnose gar, smallmouth buffalo, river carpsucker, carp, and gizzard shad make up 72.57 percent of total fish taken in gill nets and 77.99 percent of the total weight. Gizzard shad alone make up almost 54 percent of the total fish taken and river. carpsuckers account for over 35 percent of the total weight. White bass and channel catfish are the most abundant of the game fish. Fishing pressure for white bass is heavy and angler success is considered good. Lake Buchanan is considered a good largemouth bass lake by fishermen and seasonally, white crappie are also taken in large numbers. No extensive management practices are being considered for this lake. San Gabriel and Brazos Rivers Ten net collections were made on the San Gabriel River and 11 seine collections from the Brazos River. The collections were made primarily to keep familiar with the waters, check possible pollution sources, and to note physical changes in the stream systems. Seine collections from the Brazos River include five species not included in thos, taken during the basic survey, namely: Notropis venustus, Notemigonus crysoleucas, ictalurus melas, Lepomis microlophus, and Lepomis punctatus. In addition, Lepisosteus osseus was taken and also added to the species list but it is possible that the Lepisosteus platostomus included in the basic survey was actually L. osseus. Collection data from the San Gabriel River were too limited for conclusions. At the present time the river flow is so varied that a stable fish population does not exist. A dam is proposed for the San Gabriel River and when a definite site is selected, a more extensive pre-impoundment survey will be conducted. Lake Belton Thirty-eight net sets and nine seine collections were made on Lake Belton during the segment period. Results are shown in Table 6 and 7. For most species, population figures were similar to those in the 1958 collections. The most apparent changes involved gizzard shad which decreased in the netting collections from 47.51 percent of all fish taken in the 1958 period to 23.94 percent in the 1959 study. Smallmouth buffalo decreased from 7.85 percent of total numbers and 23.19 percent of total weight in the previous segment to 2.83 percent of total numbers and 3.76 percent of total weight in this segment. The apparent reduction in the smallmouth buffalo population was offset by a substantial increase in numbers and weight of river carpsuckers netted. The carp- sucker showed an increase from 1.94 percent of total numbers and 5.94 percent of total weight in 1958 to 6.57 percent of numbers and 13.52 percent of total weight in 1959 collections. --- Page 7 --- This lake supported a large-scale commercial fishery for several months and the primary effort of the fishermen was directed toward smallmouth buffalo. It is not known whether this fishery was responsible for a reduction in the buffalo popu- lation, but over 140,000 pounds of smallmouth buffalo were removed between July 1958 and mid-1959. The lake maintains good largemouth bass, white crappie, and catfish fishing. Fishing for both carp and smallmouth buffalo is extensive and more popular than on any other lake in the region. The creel census was utilized primarily to determine how many fishermen would take advantage of the increased bag limit on white crappie, which was initiated in an attempt to reduce a suspected overabundance and stunted population of this species. During the course of the census it was discovered that the majority of crappie taken by fishermen were too small to be utilized as food and were returned to the water, unharvested. Of 1,581 fishermen contacted during the segment period only three actually retained a limit catch of crappie (50) and four took over 25 (the previous bag limit). Aithough it was often possible for fishermen to catch many more than 50 crappie, the small size discouraged the possession of the catch. For this reason it seems apparent that the attempt to control overpopulation by an increased bag limit was initiated too late to be of value. Comments by fishermen and personal observations would indicate the program of increasing the harvest of white crappie would have been more successful if the bag limit had been raised while the population was composed of larger individuals. Anglers on Lake Belton would be willing to take 50 desirable-sized fish, but are unwilling to clean and prepare 50 small individuals. Table 8 shows numbers and size of fish caught by anglers on census days. No expansion of the data will be included as the census was limited and aimed at a specific group of fishermen. The total catch figures for Lake Belton as included here are unrealistic since the majority of bass and catfish fishermen utilize boats and not fishing docks for their sport. No attempt was made to contact bass fishermen away from the fishing docks and no attempt was made to evaluate total fishing success on Lake Belton because the manpower necessary for such an extensive undertaking was not available. The small size of white crappie in Lake Belton was shown in the catch of the anglers during the census period. Of the 2,664 crappie measured during the period, 75 percent were eight inches or less in total length and 56 percent were seven inches or less. Only 57 fish or two percent were larger than 11 inches. It must be re- membered that these are the fish that were harvested and does not include the thousands that were caught and returned to the water as being too small to keep. It is interesting to note that the 1,581 anglers contacted, fished a total of 6,872.5 hours and caught 4,944 fish. The rate of catch was computed at 0.72 fish/man hour. --- Page 8 --- Another interesting observation is the utilization of carp in the lake. A total of 1,565 carp were counted during the census, almost all taken for food, as well as for sport. Prepared by John E. Tilton Approved by (ls Spot. Project Leader Director Inland Fisheries Division Gary Wood Assistant Project Leader Date April 8, 1960 --- Page 9 --- Common Name Gar Gizzard shad Smallmouth buffalo River carpsucker Carp Channel catfish Yellow catfish White bass Largemouth black bass Texas spotted bass Warmouth Sunfish (all) White crappie Freshwater drum Totals Ts Table 1. Lake Inks Netting Results, 1959. Number 106 39 115 275 ah 361 128 22 96 74 1,952 Percent of Number 5 43 37.85 5.89 14.09 L123 18.49 0.10 6.56 1.13 0.25 0.21 4.92 3.79 0.06 100.00 2,078.42 Percent of Weight 22.68 4.72 17.56 26.20 2.68 16.47 0.63 9.05 1.64 0.16 0.05 0.39 1.74 0.03 100.00 --- Page 10 --- Table 2. Common Name Gizzard shad Carp Cyprinids (minnows) Channel catfish White crappie Largemouth black bass Warmouth Sunfish (all) Logperch Freshwater drum Totals Lake Inks Rotenone Results, July 22, 1959. Number 1,980 (approx) 1 460 (approx) ts 6 33 i 671 (approx) 2 1 3,195 Percent of Number 61.98 0.03 14.39 1.25 0.19 1.03 0.03 21.00 0.06 0.04 100.00 --- Page 11 --- 9. Table 3. Lake Inks Seining Results, 1959. Percent Common Name Scientific Name Number of Number Gizzard shad Dorosoma cepedianum 19 6.10 Spottail shiner Notropis venustus 92h 71.29 Redhorse shiner Notropis lutrensis 259 19.99 Parrot minnow Pimephales vigilax 3 0.23 Gambusia Gambusia affinis 1 0.08 Largemouth black bass Micropterus salmoides . 3 0.23 Texas spotted bass Micropterus treculi 3 0.23 Green sunfish Lepomis cyanellus 15 1.16 Bluegill sunfish Lepomis macrochirus 9 0.69 Totals 1,296 100.00 --- Page 12 --- Table 4. Common Name Longnose gar Gizzard shad Smallmouth buffalo River carpsucker Carp Gray redhorse sucker Channel catfish Yellow catfish White bass Largemouth black bass Texas spotted bass Sunfish (all) White crappie Freshwater drum Totals Lake Granite Shoals Netting Results, 1959. Number 15 176 120 56 32 12 34 22 5h Percent of Number 0.74 13.79 32.35 22.06 0.92 0.37 10.29 0.55 5.88 2.21 0.18 6.25 4.05 0.36 100.00 Weight (Lbs. ) 23.25 15.50 437.24 104.38 12.96 19.63 82.21 21.38 28.45 13.82 LD 3.69 11.89 1.38 TTT -53 Percent of Weight 2.99 2.00 56.23 13.43 1.66 2.53 10.57 2.75 3.66 1.78 0.22 0.47 1.53 0.18 100.00 --- Page 13 --- Common Name Gar Gizzard shad Smallmouth buffalo River carpsucker Carp Channel catfish Yellow catfish White bass Largemouth black bass Texas spotted bass Warmouth Sunfish (all) White crappie Totals ll. Table 5. Lake Buchanan Netting Results, 1959. Percent Number of Number 12 0.60 1,069 93-91 55 2.78 302 15.23 1 0.05 184 9.27 5 0.26 266 13.42 25 1.26 13 0.65 1 0.05 28 1.41 22 1.11 1,983 100.00 Weight (Lbs. ) 35.51 485.86 182.49 589.03 5225 108.27 16.87 186.38 27.38 8.06 0.38 2.69 16.53 1,664.70 Percent of Weight 2.14 29.19 10.96 35.38 0.32 6.50 1.01 11.20 1.65 0.48 0.02 0.16 0.99 LOO. 00 --- Page 14 --- Common Name Gar Gizzard shad Smallmouth buffalo River carpsucker Carp Gray redhorse sucker Channel catfish White bass Largemouth black bass Sunfish (all) White crappie Freshwater drum Totals Table 6. Lake Belton Netting Results, 1959. Number 114 186 22 51 28 25 83 14 2h 102 TT 51 TTT Percent of Number 14.68 23.94 2.83 6.57 3.61 3.21 10.68 1.80 3.09 13.12 9.91 6.56 100.00 Weight (Lbs.) 162.85 43.32 26.89 96.81 31.77 54.13 172.18 15.54 4o.48 11.51 43.87 16.69 716.04 Percent of Weight 22.75 6.05 3.76 13.52 4h3 7.56 2h ok 2.17 5.65 i oe. 6.13 2x33 100.00 --- Page 15 --- Common Name Spotted gar Longnose gar Gizzard shad Spottail shiner Redhorse shiner Largemouth black bass Warmouth Green sunfish Spotted sunfish Redear sunfish Bluegill sunfish Longear sunfish Totals 13. Lake Belton Seining Results, Scientific Name Lepisosteus productus Lepisosteus osseus Dorosoma cepedianum Notropis venustus Notropis lutrensis Micropterus salmoides Chaenobryttus gulosus Lepomis cyanellus Lepomis punctatus Lepomis microlophus Lepomis macrochirus Lepomis megalotis 1959. Number 23 271 a ah 27 4.36 Percent of Number 0.23 0.23 5.28 62.15 7 266 5.50 0.23 0.46 0.68 0.46 6.20 0.92 100.00 --- Page 16 --- 14, Table 8. Lake Belton Creel Census Kesults, February 5 through September 28, 1959. Species Caught Length in inches Length in inches Length in inches ec a ced da Gd a Kl ed els Largemouth black bass - il 9 ll 13 #19 21 619 2h 17 #5 5 3 il 6 7 6 2 4 @ 1 - - Spotted bass oo a 5 1 hy 2 5 2 a White creppie |6 293 625 558 519 305 216 683 uS 7 2 3 = = = = = -~ = = =~ = - Channel catfish - - - - 3 02621 1€ 12 9 ll 11 15 4 3 2 2 3 12 2 = -= = «= White bass a = 1 2 ly 1 27 2 8 Le we me mm i a i i Drum . - - - - 3 10 5 2 2 3B = = LP me we ee le ll Warmouth 2 4 3 - - ~ - - ~ - ia = me ~ oa a ~ a - ~ - «= = Green sunfish |3 7 13 6 3 - - a“ - ~_ som et lm Bluegills 28 8&2 ko 7 2 - - - - ee a ee Redear sunfish] - 2 9 2 - - - = - < = - = ms - - - - = - - - - U t 8 = t 1 t i} ' i] t 1 L) Q i i] i) 1 t t ' i} i} Longear sunfish Carp se 3 1 4k 56 132 201 456 392 y2 46 18 16 9 9 17 59 19 22 20 1 2 Buffalo - - - = 1 - 10 10 #5 18 8 6 7 2 = 4 13 - 2 = = « Gar Totals totel fishermen 1,581 totel fish L, 94h totel hours fished 6,872.5 totel fish/man-hour 71938