Journal of the Southeastern Association of Fish and Wildlife Agencies

Six stocks of Southeastern Micropterus were spawned in earthen ponds, including wild-caught adults of M. coosae (Alabama and Apalachicola races), M. p. punctulatus, M. punctulatus henshalli, and M. notius, and hatchery stock of M. dolomieui. Fry were reared in earthen ponds provided with Pimephales promelas forage. Periodic samples were preserved to determine pigmentation characteristics at different ages and sizes. An illustrated key to species was prepared based on length and juvenal color pattern. Wild-caught specimens of M. salmoides were included for comparison. Color pattern changes progressed at a smaller size in stunted and wild-caught young.

Brood stock of basses were obtained from the following locations during March to April, 1969; Micropterus coosae (Alabama race), Alabama River system; M. coosae (Apalachicola rate), Apalachicola River system; M. notius, Suwannee River system; M. punctulatus henshalli, Tallapoosa River system; M. p. punctulatus, Apalachicola River system; M. dolomieui, Mammoth Spring National Fish Hatchery, Arkansas. Adult bass of each stock except Suwannee bass spawned during April 5 to May 19, 1969, in 0.04- to O.l-acre earthen ponds when stocked at 50 to 100 per acre. Suwannee bass possibly had already spawned in their native habitat. However, Suwannee bass spawned in April during both 1970 and 1971. Surface water temperatures and dates when eggs were first observed were as follows: M. p. henshalli--69 F (April 5, 1969); M. coosae (Alabama race)-73 F (April 14, 1969) ; M. dolomieui--73 F (April 16, 1969); M. p. punctulatus-74 F (May 3, 1969); M.

Seven ponds in South Alabama were stocked with Florida largemouth bass, Micropterus salmoides jloridanus (Lesueur), seven with native largemouth bass, M. s. salmoides (Lacepede), and seven with F, bass. Samples of bass were collected one and two years after stocking to compare growth rates. Major objectives of this study were: to determine which of the three strains of bass grow faster and/or larger in Alabama ponds, to determine if jloridanus can be successfully introduced into an established fish population of a 1,000 acre lake, and to compare the effectiveness of the three strains of bass in maintaining a balanced fish population. All three strains of largemouth bass displayed rapid growth in ponds which did not contain a crowded bass population. The fastest growth observed was that of the F, bass. However, sufficient data has not been obtained in this study to fully evaluate the growth potential of the three strains of largemouth bass. Further evaluation is planned.

Five data collecting stations were designated within Wilkes Reservoir, a 900 surface acre power plant reservoir in Marion County Texas, to gather information relative to the effects of a steam-electric effluent upon aquatic life. Temperature and dissolved oxygen readings were obtained with a YSI model 51A oxygen meter. Readings taken at designated intervals indicated the degree and extent of the heated water. Dissolved oxygen readings indicated no adverse dissolved oxygen concentrations. Twelve species of fish were collected and examined for external and internal parasites. Almost 59% of 161 game fish specimens, and almost 83% of 50 rough fish specimens were parasitized with trematodes, nematodes, cestodes, acanthocephalans, and parasitic copepods. The extent of parasitization in this reservoir indicated optimum or near optimum temperature conditions throughout the year. Parasitic copepods were more evident on bullhead catfish (lctalurus sp.) during February, March, and April.

In 1967 the Arkansas Power and Light Company and the Arkansas Game and Fish Commission cooperated in a joint project to determine any changes in the stratification, flow pattern, and basic water quality in the lower end of Lake Catherine and in the Ouachita River below Remmel Dam as affected by the increased cooling water output and water temperature resulting from the construction of a new power unit proposed for the Lake Catherine Steam Electric Station, Hot Spring County, Arkansas. A follow-up study of the project was conducted in the summer of 1970 to obtain post-installation data to be compared to that information recorded previously in 1967. In connection with this project, nine gill netting samples were made during the period February 25, 1970 to January 16, 1971 to determine the effects of the plant effluent on the distribution of fishes within the receiving embayment.

During the winter of 1970-71, thirteen species of warm-water fishes exhibited external symptoms of gas-bubble disease (mostly "pop-eye") in the discharge canal and cove of a steam generating station. Peak monthly incidences were 70.8, 33.3, and 23.5 percent for white bass, threadfin shad, and bluegill, respectively. Forty-nine percent of the bluegill in excess of 4 inches were afflicted, whereas only 4.4 percent of those under 4 inches exhibited symptoms. Among the bluegill, the right eye only symptoms were more prevalent than were the left eye only symptoms at the 97.5 percent confidence level. Dead fish, principally black crappie, observed in the discharge in February, 1971 did not exhibit external symptoms of gas-bubble disease. However, autopsies of dying black crappie revealed gas emboli in the larger vessels of the gill fragments.

Abandoned manganese strip mines in Smyth County, Virginia have for many years contributed pollution to the streams draining them. Streams in the Cripple Creek drainage area were sampled during the summer of 1967 to determine the nature and extent of pollution in them, and to evaluate the reclamation work being done by the United States Forest Service. Affected streams were compared with control streams on the basis of physical, chemical and biological properties. Manganese levels in all streams sampled were found to be below one part per million. A controlled experiment with Mn(NO')2 showed that the median tolerance limit for rainbow trout fingerlings is about 16 ppm Mn, which, together with stream sampling data, indicates that manganese is not present in toxic concentrations in the study streams. Killinger Creek, which drains a partially reclaimed area, was found to support fewer species of fish and benthic fauna than Crigger Creek, a comparable control stream.

This research study was designed to determine the degree of damage, if any, to fish populations resulting from channelization, and to determine the rate of recovery, if the damage was significant. This study points out the detrimental effects stream channelization has on fish populations and on the flora and bottom fauna of streams. The study also indicates that following channelization, and with no channel maintenance, nature can ultimately restore a coastal plain stream and its fish population to a stage reasonably near its natural condition, provided no further alterations of the stream bed, banks, forest canopy, or aquatic vegetation occur.

Caged Tilapia aurea were cultured for a 10-week period in four experimental ponds (between 10 and 26 acres) to determine how efficiently these fish are able to use plankton as a source of food and to determine the value of Purina Trout Chow and Auburn No.2 as supplemental rations for caged T. aurea in two common types of fertile farm ponds. Fingerling T. aurea were stocked at the rate of 150 fish per 0.25-cubic meter cage (0.956 pounds per cage). There were four cages per pond. Blooms of plankton were produced by inorganic fertilizer in two ponds which contained established bluegill-bass populations, and blooms of plankton were produced by a combination of supplemental feeding of catfish and inorganic fertilizer in the other two ponds which contained catfish under intensive culture. One cage of T. aurea per pond received no supplemental ration. Three cages of T. aurea received supplemental rations six days per week.

The digestibility of nutrients in six semi-purified rations containing variable levels of protein, cellulose and starch by channel catfish in troughs was evaluated by using chromium oxide as an inert reference in the feeds. Excreta were collected using an indirect trough collection method and a direct intestinal collection method. Digestibility coefficients determined on excreta collected in troughs were higher than coefficients determined from excreta collected from the intestine. There was no significant difference in protein Or fat digestibility from the six rations when the trough collection of excreta method was used. In the intestinal collection method, excreta were collected, separately, from four areas of the digestive tract, namely, the stomach, upper intestine, lower intestine and rectum. The absorption of protein in twoyear old channel catfish occurred the length of the intestine up to and possibly including the rectum.

A number of studies have been done on the tolerance of fish to salt, but there is little information on the effect of salt on growth of fish. In the present study, repeated trials in tanks indicated that selected concentrations of salt have a significant effect on the growth of channel catfish. Subsequent trials in ponds showed a similar effect. The increased growth resulting from selected concentrations of salt is of such magnitude as to be of practical significance in some situations. An explanation for this effect is postulated.

This paper includes a discussion of a catfish polyculture experiment conducted in brackish water ponds at the Rockefeller Wildlife Refuge, Grand Chenier, Louisiana. Ponds containing channel catfish (1ctaluTUs punctatus) only served as controls and were compared to other ponds containing various stocking ratios of blue (1. furcatus) , channel and white catfish (I. catus) to determine if production could be increased. Length-weight relationships, coefficients of condition, food conversions, survival and growth data were compared in an analysis of the various stocking combinations. These data supported by that of past studies demonstrated that channel catfish grown under monoculture conditions exhibited the best survival, food conversion, coefficient of condition and growth. It is also stressed that we believe the culture of mixed species to be nearing practicality and may be a future requirement in order to realize additional profits from fish farming operations.

Vitamin fortification of the Auburn No.2 pelleted fish feed increased net production of channel catfish an average of 19.3 percent in feeding tests conducted in replicated earthen ponds between April 13 and November 9, 1970. A stocking density of 4,000 fingerlings acre was used and the fish were fed 6 days per week. In comparison to a second commercial catfish feed containing identical v\\tamin fortification the fortified Auburn No.2 feed produced an increase in net production of 39.5 percent. Feed conversion, gain per day and average weight of fish at harvest were all superior with the fortified Auburn No.2 feed when compared to the other two rations.

Channel catfish virus disease is caused by a specific virus which has been isolated from 23 epizootics reported from nine different states. This paper gives clinical signs, mortality patterns and susceptibility of different age and size fish to channel catfish virus. Recommended practices for controlling the disease are presented.

"Red-sore" disease of fishes caused by the stalked ciliate Epistylis, is very common and widespread in the Southeastern U. S. Epizootics occur most frequently during the winter and spring months. Research has shown that this species is not an obligate parasite but only uses the host fish as an attachment site. The disc-like attachment organelle, penetrating the skin of the fish, apparently secretes an enzyme that dissolves the fishes' scales or spines and produces pit-like inflamed lesions. Bacterial infections often occur secondarily to the Epistylis infestation. Observations of the life history have shown a formation of telotrochs which are characteristic of the order Peritricha. Preliminary laboratory tests show that a single treatment with potassium permanganate at a rate of 2 ppm or formalin at a rate of 15 ppm will control Epistylis.

This is the first report of Goezia sp. from freshwater fish in North America. Extensive mortalities among striped bass (Morone saxatilis) resulted from the damage caused by these nematodes. A possible mode of infection is given and a discussion of the pathology associated with the worms is presented.

The use of fluorescent labelled antibody (FA) systems provide a means for detecting both the presence of the agent, Aeromonas liquefaciens and fish antibodies to that agent. Bacteria from experimentally infected fish could be identified within 6 hours after obtaining the sample by the FA technique. The preparation of specific antiserum to A. liquefaciens and a proposed method for rapid detection of the bacterium from field specimens is presented.

Various stocking rates were tested over a three year period for production of striped bass in culture ponds. Rates ranged from 10,000 to 160,000 fry per acre. Results indicate higher rates produced as high a percent yield as lower rates. Four food types were also tested during this period to determine which produced the best yields. Commercially prepared supplemental feeds did increase production over natural foods. Food habits data support earlier information that Copepoda, Cladocera and Insecta are important food organisms to juvenile striped bass.

The investigation to verify striped bass, Morone saxatilis (Walbaum), reproduction in Keystone Reservoir utilized egg sampling and shoreline seining methods. Conditions in the Arkansas River throughout the egg sampling period were unfavorable and seemed to indicate little chance for a successful spawn. However, on June 21, 1971, natural reproduction was verified. The total 1971 fingerling survival was calculated at 975,000. Ten mature females and four male striped bass were taken below Keystone dam by electrofishing during the period May 24 to June 3, 1971. These fish were transported 150 miles to hatchery facilities where artificial spawning was conducted. One seven-pound female was successfully spawned and fry were produced. Problems, procedures and resulting recommendations are discussed. Age and growth determinations and length-weight relationsips are presented.

Stomach content analyses were performed on 213 striped bass (11.480.0 mm TL) collected from culture ponds at the Front Royal Fish Cultural Station, Virginia, during the 1969 and 1970 rearing seasons. Cladocerans (families Sididae, Daphnidae and Bosminidae) constituted the major portion of the diet of these fish with copepods (family Cyclopidae) and insects (family Chironomidae) also being important food organisms. Cladoceran abundance in the stomachs increased after the bass were 30-40 mm long, while copepod abundance decreased and insect abundance remained relatively stable. The fish negatively selected Brachionidae (rotifers) and copepod nauplii. Daphnidae and Bosminidae were positively selected and Cyclopidae was eaten in relation to its abundance in the ponds. Sididae was positively selected when present in small numbers, but eaten in proportion to its abundance when present in large numbers.

The ovaries of 28 mature female hybrids, striped bass Morone saxatilis (Walbaum) X white bass Morone chrysops (Rafinesque) from Lakes Hartwell and Clark Hill were utilized in determining fecundity in this oviparous species. These data were collected from all year classes present that were sexually mature, which included year classes I, II, and III. No females of year class 0 were captured during these studies. Many hybrid males one year of age were caught at the spawning grounds and specimens as small as 269 mm in total length appeared to be sexually mature. Female hybrids as small as 409 mm in total length and some weighing as little as 917 grams were found to be sexually mature. Mean ova production although increasing in direct proportion to age, total length and body weight remained rather constant as to average number of eggs per pound of body weight.