TPWD 1957 F-4-R-4 #272: Report of Fisheries Investigations: A Study of Crappie in Lake Whitney

.. 1 4 ”I” ‘ " f / i 36 3 3555;“ 0 6/3 H24. #237 Report of Fisheries Investigations A Study of Crappie in Lake Whitney by Robert N. Hambric Assistant Project Leader DingelleJohnson Project Feuuamh,_Job E-h November 1, 1956 1 October 31, 1957 ' H. D. Dodgen w Executive Secretary Texas Game and Fish Commission Austin, Texas Marion Toole William H. Brown Coordinator _ Assto Coordinator SEGMENT COMPLETION REPORT State of TEXAS Project No. Fth Name: Fisheries Investigations and Surveys of the Waters of Region uB. Job No. Eek Title: A Study of Crappie in Lake Whitney. Period Covered: November 12 l9§6 through Octdber 312 1957 ABSTRACT: A study was made of the crappie in Lake Whitney, a large clear water impoundment, from November 1956 through October l957. various models of wire traps were evaluated as to their ability for capturing crappie. Small traps were constructed and used to sample the crappie fry population. The fry grew from a total length of 70 millimeters in June to a length of 1%? millimeters by the first of October. Over 5700 fish were trapped» about 30 percent were crappie. About 850 crappie were tagged and returns from 3% of them were evaluated. The crappie are nomadic in Lake Whitney and seldom occupy one site for any extended length of time. The harvest of crappie by fishermen apparently is related to how much is known regarding the location of the fish at various times of the year. The chemical stratification of the impoundment is affected by the prevailing south and southwest winds and fluctuates considerably during the summer. The crappie migrated vertically, as well as horizontallyfy as the.carbon dioxide and oxygen content of the water changed at different depths. -/ A study was made of the effects that an abundance of organic materials has on the oxygen and carbon dioxide content of the water when the take was at flood stage as well as following the flood. it was learned that a bacterial type of disease which infects the crappie occurs on less than one percent of the population. Two institutions were contacted for a more complete identification of the disease. cmmscrivss : To determine the population of crappie in Lake Whitney and the reasons for the recent small harvest. Study the pattern and extent of travel of tagged or marked crappie and the_ecological factors influencing their distribution. To develOp satisfactory methods of sampling crappie fry and study the effects of a bacterial type of infection found on some of the crappie. HISTORY OF CRAPPIE HARVEST: Data from the creel census that was worked on Lake Whitney from August 1953 through October 1935 revealed that fishermen caught 87 pounds of crappie per surface acre from that lake during the 27mmonth period (Job Bel June 1, l953aOctOber 31, 1955). The creel census also showed that the harvest of crappie was not as good during l955 as it had been in the two previous years. From January through OctOber 195% fishermen averaged catching 0.32 crappie per hour of fishing time. During the same period of 1955. fisher» men caught an average of only 0. l0 crappie per hour of fishing time. Many anglers have complained of the poor results obtained from crappie fishing during the past few years. ' The sharp decline in crappie harvest was the primary reason for the current survey.) TRAPS AND OTHER METHODS USED IN MAKING COLLECTIORS: The main gear used for collecting crappie was wire traps. The type of trap used most intensively was constructed of six gaub we concrete reinforcement mesh measuring 6 by 6 inches to the mesh. A sixefoot section of the material was rolled into a cylinder al.lowing two meshes to overlap. This formed a round body for the trap and added strength and rigidity to the structure. The frame was lashed together with soft iron wire and ' covered with eneminch mesh chicken wire. This made a trap 23 inches in diameter'and 5 feet long. Funnels made of chicken wire. with a 6minch Opening at the apex, were lashed into one end or sometimes both ends of the trap. A door made of geinch hardware cloth. and of sufficient size to overlap one of the 6minch'by 6minch mesh of the wire frame9 was located at one end of the trap. usually the end Opposite the funnel on the single throat traps. The door was hinged with wire rings and held closed with a snap fastener. This allowed an ' easy and rapid means of taking fish from the traps. The single throat trap weighed 19 pounds and cost $2. 50 for material. Several variations of the trap were used. They ranged from 19 to 29 inches in diameter. Single throat as well as double throat models were made. Traps with frames welded from 3/8einch reinforcement steel were also tried. These trapS‘were also covered with iminch mesh chicken wire and measured 29 inches in diameter by 6 feet long. Both single throat and douh e throat versions were used. Small traps constructed of an minch‘mesh hardware cloth were made to capture crappie fry. The traps were made in single throat and doub e throat models and ranged fl em 13 inches to 18 inches in diameter. A.l traps were 36 inches long. Three different sise openings in the small and of the throats were experimented with; namely lgcinchg 2ei.nch and 2 ?;”8e inch. All traps had a nylon hand line with a yellow indentification block floated at one end. Gill nets were used to check the population of all species of fish and to supplement the data for the c:rappie study. Most of the gill net sets were made during the high water period when many of the trapping sites were completely flooded and the traps could not be checked. The amount of netting done was limited by the time available for such operae tions. A small number of hoop net sets bai ted with cottonseed- cake? were made. The same type of net had been used before“iand the results had not been encouraging. it is possible that hoop nets with their throats arranged differently from those that were used could be beneficial in a crappi e survey Liquid rotenone and rotenone powder were used to sample several stations. The liquid I rotenone (Chemfissh regular and Chemfish special) was tried along rock bluffs and in isolated deep and medium deep coves. The five percent powdered rotenone was used to supplement minnow seines in the checking of seine stations. 3. A rather intensive seining program was carried on. primarily at the time when the lake was in flood stage as the high water followed the spawning time for most species of fish. The seining was done with l/Bainch mesh common sense minnow seines 20 feet long and 3/l6ninch mesh tied seines 15 feet long. Our main Objective in all of the seine Operations was to locate crappie fry and the fry of largemouth bass. Hook and line sampling was tried at two or three stations in conjunction with the traps that were used on those stations at that time. METHODS OF RECORDIHG DATA: we found the most effective method of keeping records of our trapping stations. while working in the.field. was to use a separate card for each station. File cards measuring 5 by 8 inches were found to be a handy size to use. The location and descripu tion of the station. as well as the kind of trap used and the depth of the set. were placed at the top of the card. Each time the trap was run we recorded the date. a detailed description of the catch and the surface temperature. Notes were occasionally made on the cards concerning items of specific interest to that particular catch or station. As a card became filled with information. or if the station was changed or abandoned. the data card was transferred from the active field file to a permanent file in the regional office. Data concerning tagged fish were handled in a similar manner. Each time a tagged fish was captured a card was filled out for that particular fish and placed in the office files. A system of crossfireference was devised to simplify correlating the data between fish tagged and those recaptured. All water analysis data were recorded on physical chemical field record sheets. Printed posters which contained information about the crappie trapping and tagging 1 program were displayed at many of the business sites. fishing camps and concessions throughout the lake area. Small cards. which contained pertinent information regarding- . the data that was desired from captured tagged fish. were widely distributed around Lake Whitney. Additional publicity was obtained through newspaper articles and speeches made at meetings. RESULTS OF TRAPElldt Trapping stations were established from the upper part of the lake at White Bluffs to Little Rocky near the dam. a distance of l5 to 20 miles. These stations cowered all major areas of water with the exception of the upper third of the lake where the impound: ment is confined to the second banks of the Brasos River. However. a large part'of the trapping was done in an area about seven miles long between the Katy Railroad Bridge and. .Bear Creek. Consideration was given to compressing the scope of the survey to a manageable size and estahlishdng a number of permanent assessable stations. A maximum of 28 traps were used at any one time. The first traps were set in Lake Whitney November ll. lQSS and trapping continued V through Octoher l957. During that time 138 stations were sampled with wire traps and “59735 fish were captured. White crappie accounted for 1.733 or nearly 30 percent of the total fish caught. Only six black crappie were captured during the trapping period. Twentyutwo species of fish were trapped plus a few snakes. crayfish and turtles. Bluegill were the most abundant species taken and accounted for about onemhalf of the entire catch. Table l lists the number of each species taken and the percent of the total catch that they represent. - -. .. . . _ _ . - ._ . .. . . ..,. . , .. . H... .._...._..._.... w_.._' ,.. Traps constructed of one-inch mesh chicken wire stretched over a frame of concrete reinforcement mesh were found to catch satisfactorily. Sizes smaller than 23 inches in diameter are not recommended. The traps with frames welded from 3/8ainch reinforcement steel and measuring 29 inches in diameter and 6 feet long caught larger samples of crappie than any other type trap but they are quite heavy to handle. The heavy trap is not recommended for use except in very limited numbers. Both double and single throat traps were about equally effective. A 29uinch diameter trap made with a reinforcement rod ' frame was fairly light and captured fish very satisfactory. The trap was used with a 'single throat. ' The 16 and lBuinch diameter fry traps were successful in both single and double throat versions. lt is suggested that the size of the opening in the apex of the throat be governed by the size of the fry that one wishes to catch. A large Opening in the throat of a small trap will naturally capture larger fish'bnt it also makes it easier for them to escape. Likewise9 double throats on short traps of large diameter places the inside Openings wOf the funnels too close tojeach other. mars ems ATTRACTORS: ' Several devices were used to attract crappie into the traps. The trap containing the attractor was always set near a duplicate trap used as a control. All factors were kept as near equal as possible. Burlap strips were woven into one trap to simulate brush. The trap was set with a control trap in wanna Canyon and checked 8 times during 15 days. The burlap trap captnred four crappie and a total of seven fish. The control trap caught 9 crappie and a total of l3_fish. The experiment was also tried along a rock bluff but little success was had with either trap. Burlap cloth was used to cover one trap completely except the end which contained / the throat. The trap was set with a control trap in water 9 feet deep. The burlap covered ‘ trap caught only hluegillsg 39 in number. The control trap captured 16 hluegillsg l largemcuth base? i white bass and l carpsucker for a total of 19 fish. Neither trap captured crappie. The traps were checked 9 times in a El day period. Minnows were confined in a wire mesh.hor within one trap which was set feet from a control trap. All known factors were equal. Both traps were examined 5 times within 10 days. The trap containing minnows captnred 28 crappie and a total of 36 fish. The control trap caught seven crappie and a total of eight fish. The experiment was terminated by a very l rge rise in the lake level. 53 '4 .A punctured can of sardines was suspended by wire within one trap. The control trap was set 90 feet awa . Both traps were set eight feet deep in Wanna Canyon. .All known factors were equal. The traps were checked twice in four days before the experiment'was terminated by the flood. The trap containing the sardines caught five crappie and a total of twentymfour fish. The control trap captured no fish. lh:: t; ad throughout the survey that a new trap appeared to he more successful than an old trap in capturing crappie.' Traps that became covered with silt or sediment rarely made good catches of fish. It has been suggested that the light reflecting qualities of the new and brighter traps may have been the attracting factor. Experiments will he cone ducted on that theory. .9 ..... ZITIEs .315. 2 Several ap; e we.s tagged and 106d in the tray“ to learn how long it would tare for the - ”h v0 85C 36- In 31' sirtywseven fish ce returned to the traps. VrHEteen escaped in one day; one w released after onu :y; five were released after ”0 days$ one was r63iised after ft ' dayS; nine escapee “ter five days; one escaped .fi a six days er“ escaped after seven days. There we“ W9 difference in the hold- ir lfi" sgle throat and dauhle fihroat traps. e11; '- .mple twentymfour stations between march and July of 1957. .e meta ' int iced seep and most of them had one and oneehalf inch mesh measured =3 the sq; . . A total of two thousand eight hundred and fifty feet of net was used. iable 2 is a tabulation of data from gill net collections made on Lake Whitney. §AMPLING WITH HOOP NETS: 1 m lake. The impoundment was still flooded at that time but was being drawn down to its normal level. There were no spectacular catches made in the hoop nets. All nets were baited with cottonseed cake. A few crappie were captured along with several other species” of fish. Frequent checks of the nets revealed that crappie could easily escape through the ringmtype throats. A fingermtype throat would have been an improvement in the catching and holding qualities of the hoop nets. THE USE OF ROTENONE: ______“______m______ Powdered rotenone and liquid rotenone were used several times at various places in the lake. Five percent rotenone powder was used at a number of shallow water stations. The major part of the sampling was done during may and June when the lake level was very high. Adequate samples of many species of fish were taken but we did not locate young crappie. which was our main objective. Liquid rotenone (Chemfish regular and Chemfish special) was used a few times to sample areas along rock bluffs and in coves. Detailed records were kept of the amount of“ time that passed before various. reactions were observed. Again, we collected several species of fish but found only two crappie fry which were captured in October while use ing the liquid rotenone in a cove. Our main purpose in using the liquid rotenone was to experiment with methods of dispersing a small quantity. We used ten ounces. far below the surface to spot check for crappie. We did not have a pump so we tried lowering the liquid rotenone twelve to eighteen feet deep in a paper bag. A rock was placed in the bag for ballast and the bag, rock and rotenone were lowered to the desired depth and allowed to remain there a few minutes. A tug on the cord then released the rock and rotenone from the wateresoaked bag. The method is obviously clumsy and, no doubt, crappie as well as some of the other fish could easily escape the slowly dispersed chemical. RESULTS OF SEINING: Our main purpose in making minnow seine checks was to locate crappie fry. Many stations were seined, a lot of them in May and June when the water level was high, and excellent samples of young fry of a number of species were taken. But crappie fry were not found in any of the seine samples. Visual reference was made as to the abundance of various species and a few choice samples were retained for future study. Some of the species were so concentrated that any effort toward evaluating each species percentage wise would have been erroneous. The species most accessible for seining were shad, carp, and white bass. Gar, bass sunfish, and minnows were also well represented in some seine samples. GROWTH AND MOVEMENT OF CRAPPIE FRY: Many questions have arisen concerning the success of the crappie spawn in Lake Whitney. We did not have enough data from the previous basic survey to intelligently .answer inquiries about the growth and movement of the young crappie in that impoundment. Gill nets were not effective in obtaining such information and sampling with rotenone and minnow seines had not produced the_desired results. Plans were included in the current survey to study the crappie spawn on an experimental scale. A number of small traps were constructed and set in the lake at various depths and _ in different types of ecological habitats. The fry traps were checked weekly from November . 1956 until a large flood occurred in the lake the last of April 1957. A number of young fish of several species were caught but only one small crappie was taken. It was captured' on the bottom of'a creek channel thirty feet deep December 10, and measured ninty milli~ meters (2 3/h inches) total length. The trapping of this specimen surprised us as we did not expect to find small crappie that late in the year. Evidently the fish was from a very late spawn or perhaps was a stunted specimen. Several of the larger traps were moved into two winding, narrow coves the fourth day of April and good catches of crappie six to nine inches long were taken throughout the month. Most of the traps were set six to ten feet deep. Most of the fish were darkucolored- males and gravid females ready to spawn. Many of the females flowed eggs when slight pressure was applied to the abdomen. Fry traps were moved into the coves April 22. We did not capture any baby crappie for the next four days, at which time the spawning sites as well as our traps were covered by the flood. Most of the available time during May and June was used in checking the shallow water of the flooded areas for spawn of crappie and other species. Minnow seines and powdered rotenone were used to capture young of a number of species of fish but we did not take any crappie fry during that time. Although the lake was on a large rise, the backwater available for sampling was usually clear due to the large amount or organic materials present. Evidently the crappie spawn did not inhabit the clear, shallow areas. Nine crappie which weighed from twentwaive to sixtyenine grams were trapped June ll in one of our regular siZe traps twelve feet down over water eighteen feet deep. The trap was set among trees on a ridge surrounded by deeper water. The lake levei was dropping at the rate of more than one foot per day at that time making it impossible to establish regular collecting stations. Therefore, we do not have sufficient data to try to evaluate the ages of that particular catch of crappie. The smaller ones could possibly have some from an early spawn but the ages of the larger ones are very uncertain. The collection is mentioned only as a point of interest. By June 25 the lake level had fallen until it was only about normal. On that day we set two fry traps in the flooded coves whe ‘ gravid females. 'On June 26 we had one tiny crappie that measured length and weighed 8 grams. This was the had taken from the lake. We trapped-Several fry in that area during the but not in the main part of the lake. The minimum water dept depth about #5 feet. The bluffs of the Brazos Rive* Regular size traps as well as small fry traps were set at the bluff.. Some of the 35 grams were taken in the traps constructed of once 1 inch mesh chicken wire. But several fry of that size hung themselves in the traps trying‘ to force their way through the oneeinch mesh wire. Hot, still days during the latter part“ of July warmed the surface water to a maximum temperature of 95 degrees F. along the bluffs. er analysis suggests that Data taken from our trap catches, as well as data from the wet ' ° ovements during the last days of July. About' July 28-or 29 the young crappie began a downward Temperature records of .ees at the lefoot depth. Chemical 17~foot depth was approaching the limit of oxygen and carbon dioxide tolerance of the fish. Changes in the condition of the water at ; sed great variation in the catch of fry at‘ Traps set at 19 feet caught two crappie. I I I l I E ! I I I I I successful. Traps set shallow in boat basins did not catch crappie fry but traps set 10 to 12 feet deep did produce fry on occasions. In some instances they did not move into the traps until after sunwup. We captured only two or three black crappie fry during the entire survey. The first fish was taken alone on August 19 at a trapping site located in a cove. The trap was set 10 feet deep. The fish was 65 millimeters long and weighed 7 grams. Another fish was captured August 20 along a rock bluff. It was taken in a trap 12 feet deep along with nine white crappie fry. The specimen measured lOO millimeters in length and weighed 10 grams. Some of the white crappie fry were of comparable size. Table 3 shows the probable trend of growth of 205 white crappie fry from June 27 to the first of October. We used only those groups of fish which we believed were approximately the same age. Even then there was considerable variation in the sizes of individual fish. ECOLOGICAL DATA: Crappie *were caught in limited quantities in fairly deep water, lb to 26 feet, along" rock bluffs and near brush from November through January. A quick drop in the surface temperature of the water always moved the crappie out of the shallow water. But if the colder temperature remained constant for as.long as ten days some of the crappie would move back into the shallow water. Very few crappie were caught in water of any depth if shelter such as brush, tree tops or rock ledges were not present. The crappie apparently moved about considerably from February through March but usually stayed in the deeper water. The crappie moved into the coves and up the Creeks during April as the surface temperature of those areas approached 65 degrees. If the temperature dropped quickly the fish moved out of the coves. A very large rise in the lake level, which began the last of April, flooded all trap» ping stations and most of the traps. There were no crappie captured in may and only a few were taken in June. The fish were captured fairly shallow and none were taken in the sheltered areas which contained lots of carbon dioxide and a small amount of oxygen. Some crappie were captured in the protected coves during'July but many of the fish died in the traps at night. Most of the crappie moved out of the coves and many were captured along the rock bluffs during the latter part of July and most of August. The most productive “depths along the bluffs were between 12 and 19 feet. The water began to cool during September causing the crappie to move around a lot. They were never concentrated in any one place for very long from the middle of September through October. Good harvest of large crappie were made by fishermen at times during late September and early October. The fish weighed from 12 to 16 ounces and were of a size group that had never been caught before in quantities. The run of large crappie was noticed over the entire lake and was reflected in our trap catches. 'Eowever, the duration of the run was too short for us to track the run with our traps or gain much information about it. The prdblem of an inadequate harvest of crappie in Lake Whitney could perhaps be solved by more accurate knowledge of the habitats preferred by the fish under various conditions. Crappie are quite nomadic in that impoundment and their movements are not I easy to follow or predict. I TAGGED FISH: .A strapmtype jaw tag, number one size, was used to tag<approximately 850 white crappie between February 13 and October 9, 1957. The tag was attached to the premaxillary. Anesthetics were not used. The total length was recorded in millimeters and weight in grams. The tag number, date and place of release are also recorded.' We had 3% returns or A percent of the total number tagged. Several of the fish were retrapped by the biological crew and the remainder were reported by fishermen. Two were retrapped twice. A large number of fish were tagged in two neighboring coves. Both coves are long and winding and are known locally as Wanns Canyon and Juniper Cove. The returns from the fish tagged in the coves are of interest. A very large rise in the lake level - interrupted the tagging program from April 26 until June 11. A total of 98 crappie were tagged and released in Juniper Cove between April 3 and April 26. Thirteen of the fish were recaptured before the lake flooded. Nine of them were recaptured in Wanna Canyon and one was retrapped in Juniper Cove. One was captured by a fisherman as it was apparently leaving wanna Canyon, two other fish were caught after they had left the canyon. Two crappie, from the group of 98 were captured by fishermen far down the lake after the impoundment had flooded. NOne of the fish were recaptured in the canyon after the flood. Another group of 57 fish were tagged in wanna Canyon after the lake had flooded (June ll to August 7). Fishermen caught three of the fish. One was captured within the canyon and two others had moved out a short ways. A total of 88 crappie were tagged and released in Juniper Cove between April 3 and April 26. Eight of the fish were recaptured before the lake flooded. Six of them were retrapped within the cove and two were retrapped in Wanns Canyon, a neighboring cove. A fisherman captured one of the fish a short distance out of Juniper Cove after the lake had begun to rise. Another fish was caught far down the lake when the impoundment was at high flood stage. None of the fish were recaptured in the cove after the flood. Sixty seven tagged fish were released in Juniper Cove after the flood (June 11 to August 7). Two of the fish were retrapped in the cove. None of the other fish were recaptured. The free for one month. The other fish was.trapped near deep water in Helms Cove, up lake from the bluffs, about one week after it was released. The last two fish discussed were tagged on the same date from a single group of fish. We thought it quite interesting to note that not a single crappie was recaptured along the Brazos River Bluffs. Although we tagged 186 fish at the bluffs following the flood and captured nearly 500 crappie there, we did not retrap a single tagged fish. It should be mentioned that we had a large number of times. The dissolved gases and pH were analyzed according to standard biological methods. The temperatures were taken with an electric, directureading thermometer. The temperature readings made June 19 were taken with a stem glass thermometer. '