Journal of the Southeastern Association of Fish and Wildlife Agencies

Thanite (82% isobornyl thiocyanoacetate) has been used as a fish management tool on International Paper Company's Southlands Experiment Forest since 1968. Annually, Experiment Forest personnel successfully move 2.000 to 4,000 largemouth bass (Micropterus sa/moides) with an 0.8 to I ppm (active ingredient) mixture of 80%Thanite - 20% Atlox 1045-A. Collection and survival percentages are higher when water temperatures are less than 70°F. Collected fish are placed in cans of untreated water in collection boats and later transferred to an aerated holding tank. Recovery in the tank is usually rapid and survival exceeds 90%.

An extreme drawdown conducted on Lake Tohopekaliga, Florida. improved littoral substrate. stimulated development of aquatic macrophytes and increased invertebrate standing crop. Benthic macroinvertebrates increased from 98 to 244 organisms per square foot in limnetic areas after reflooding; littoral benthos rose from 154 to 250 organisms per square foot. Phytomacrofauna increased from a predrawdown high of304. to 1364 organisms per sample unit after reflooding, Standing crops decreased to predrawdown estimates within two years following peak production periods. These decreases were attributed mainly to predator cropping. Fish food organisms were favored by the drawdown, and their incidence in largemouth bass stomachs increased. As a final expression of increased production. sportfish populations which utilized these organisms nearly doubled.

An extreme drawdown conducted on Lake Tohopekaliga rejuvenated littoral substrate, stimulated development of desirable aquatic plants and increased macroinvertebrate production. As a result of these beneficial changes standing crops offish in littoral areas increased from a high of 191 pounds per acre before the drawdown to 455 pounds per acre within two years after reflooding. Limnetic standing crops increased from 59 pounds per acre to 127 pounds per acre during the same period. Biomass of sportfish neady doubled, although forage fish accounted for a higher percentage of the population fonowing reflooding.lndividual species response to the drawdown varied. Numbers of harvestable size sportfish increased following reflooding. The monetary value of the Lake Tohopekaliga fishery increased by 37 percent, or $6,222,186.

A 15-month study of a natural tidal pass on the southeastern Louisiana coast revealed that the pass and adjacent inshore waters are utilized by a variety of immature fishes as immigration pathway and! or nursery. Eighty species representing 39 families were found to occur in the pass area, including young of several commercial and sport fishes. Two seasonal assemblages of immature fishes were identified, cold- and warmwater. Coldwater species were mostly immigrating young of offshore spawners, while warmwater spec'es were mostly young of inshore spawners. The catch of coldwater species was lnfluenced more by tidal stages than light periods; warmwater species exhibited varied diel catch patterns but the catch of predominant warmwater species was more closely associated with light periods than tidal stages. The similarity in diel patterns exhibited by some of the coldwater assemblage indicates that this group may react similarly to the problem of inshore transport (immigration).

A long-haul seine was designed to sample 10,000 m2 of open water less than 3.5 m deep for both pelagic and semi-demersal fish populations. The net, 354 m long constructed of 20 and 25 mm bar mesh. was used to encircle the area, and by a simple method to concentrate and purse the catch in open water. Atlantic menhaden, Brevoortia tyrannus; Atlantic thread herring, Opisthonema oglinum; pinfish, Lagodon rhomboides; and striped mullet, MugU cephalus were the most abundant species collected from 60 samples taken during 1973 in the Newport River estuary (Carteret County, North Carolina). Sample to sample variation for individual species was high, with coefficients of variation usually about 100%. Mark-recapture experiments using a total of 232 marked fish indicated that 31 to 54% (95% confidence limits) of the marked pelagic and semi-demersal fish released in the sampled water mass were recovered.

Tests were conducted to determine (1) the acute (96-hour) toxicity of hexachlofobenzene (HCD) to pink shrimp (Penaeus duorarum), grass shrimp (Palaemonetes pugio), sheepshead minnows (Cyprinodon variegalus) and pinfish (lAgodon rhomboides) and (2) the rate of HCD uptake and depuration by pinfish. Hexachlorobenzene was not acutely toxic to any of the animals tested at measured concentrations in sea water to 25 ug/1. However, both species of shrimps in the highest HeB concentration were lethargic as compared to controls and exhibited an uncharacteristically white hepatopancreas at the end of the 96-hour exposure. Pinfish exposed to average measured HCB concentrations of 0.06, 0.15, 0.65, 1.87, or 5.2 ug/1 for 42 days accumulated the compound throughout the exposure. Maximum residue in muscle (wet-weight) was 34,000X the measured concentration in test water. Pinfish retained most (>50%) of the HCB after a 28-day depuration period in HCB-free water.

Acute (96-hour) bioassays were performed with endrin and the following estuarine organisms: American oyster (Crassostrea virginica), pink shrimp (Penaeus duorarum), grass shrimp (Palaemanete's pugio). sailfin molly (Poecilia latipinna) and sheepshead minnow (Cyprinodon variegatus). Endrin was acutely toxic to all organisms tested, except oysters, whose shell growth was appreciably inhibited by 56 ug/1 (parts per billion) of the chemical. Pink shrimp were the most sensitive animal tested, but significant numbers of both species of shrimps and fishes died when exposed 10 concentrations of one ug/1 or less, In a separate test, embryos and fry of the sheepshead minnow were exposed to concentrations of endrin ranging from 0.046 to 1.0 ug/1 (nominal) for 33 days in an intermittant-flow bioassay. Embryos were not affected by the concentrations to which they were exposed, but the estimated LC50 (prohit analysis. a=.05) of fry was 0.27 ug/1.

An investigation of the effect of two feeding rates on pond production of advanced fingerling striped bass was studied at the Auburn University Fisheries Research Unit from June 27 to November 24,1972. The mean survival for fingerlings fed a high feeding rate was 71.87% as opposed to 70.13% for fingerlings fed a low feeding rate. Mean production for fingerlings fed a high and low feeding rate was 266.44 kg/ha and 293.68 kg/ha. respectively. Food conversion for fingerlings fed a high feeding rate was 3.74 as compared to 2.51 for fingerlings fed a low feeding rate.

The effects of increased water hardness. salinity. and source of fry on the survival and growth of striped bass fry from three females from the Cooper River, South Carolina. and two females from the Savannah River. Georgia. were studied at the Fisheries Research Unit. Auburn University, from 6 April to 11 June. 1971. Fry were stocked in one ofthree water treatments: control with a total hardness of 30 to 40 ppm; added hardness. 125 to 175 ppm; and added salinity, (chlorides) 1,100 to 1,500 ppm. Variance tests for homogeneity and contingency tables were employed for data analysis. Survival of striped bass fry was increased in the added salinity treatment. Fry survival in the control and added hardness treatments appeared to be dependent on the fry groups rather than the effects of the treatments. The survival of Cooper River fry appeared to be more variable in water with added hardness; Savannah River fry survival was more variable in the control treatment.

The use of suitably constructed and located stock water ponds for food fish culture is recommended, based upon investigation into the possibilities of these small bodies of water to rear a channel catfish-largemouth bass combination. Stocked with 2,000 catfish and 100 bass per acre with supplemental feeding, two, two-year production cycles showed the following results: total fish production, 2,634 and 3,791 pounds per acre; feed conversion, 2.5 and 2.4; recovery of stocked catfish, 84 and 91 percent; recovery of stocked bass, 40 and 50 percent. In addition to supplying food fish, the pond provided recreation through the fish cultural activity and by hook and line fishing.

Channel catfish were stocked in 27, 1/10-acre ponds at the rate of 3,000 per acre and fed nine commercial-type rations containing three protein percentages and three levels of fish meal for 200 days. Average survival for the experiment was 96.8% and 93% of the fish were over 12 inches in length at harvest. Average yield for treatments ranged from 2,330 to 3,030 Ib/acre and the average for all treatments was 2,638 lb. The results indicated that satisfactory production can be obtained with all-plant rations. The 29%. all-plant protein diet yielded 2,330 Ib/ acre of harvestable size fish. Increasing total protein in the all-plant rations to 36 and 43% resulted in production of 2,475 and 2,640 lb/acre, respectively. Replacing 1/6 of the plant protein with fish meal protein, at the 29 per cent protein level, increased production by 100 Ib/acre; however, replacing 1/3 of plant protein with fish meal protein yielded an increase of 430 lb.

Pupae of face fly (Musca autumnalis De Geer) were offered to channel catfish flngerlings fed outdoors in plastic pools. Other channel catfish fingerlings received rations of equal parts of face fly pupae and Purina Catfish Cage Chow (pellets) or pellets only. After 9 weeks of feeding, catfish from each pool were counted and weighed. Survival rates were 94. 97. and 93% and ratios of dry weight of food to increase in live weight of fish were 1.62, 1.77. and 2.29 for fish receiving pupae, pupae and pellets mixed, and pellets only, respectively. There were no statistically significant differences between these values (P=.05).

Albino and Donnal channel catfish, lctalurus puncta/us (Rafinesque), were stocked in suspended cages in a pond at densities of 11.1, 13.9 and 16.7 fish per ft3, respectively, with two replications of each. There wefe no apparent growth or sucvival differences between the albino and normal channel catfish. Mean gain/fash and mean gain/cage/day were significantly different (P 0.01) between the two higher stocking densities with both types of fish. These data indicate that a standing crop of about 15 Ib per ft of cage is the maximum which can be grown in still water ponds.

Macrophyte standing crop (primarily Eleocharis and Utricularia) was reduced nearly 90% in two catfish ponds after introduction of grass carp (Ctenopharyngodon idella). Abundant vegetation remained in 1-m2 exclosures placed in the ponds as controls. The stocking ratio of grass carp (live weight) to macrophyte standing crop (dry weight) that resulted in vegetation control within 1 year was 0.15 in the pond is which the fish were fed pelleted food and 0.06 in the pond in which the flsh were not fed. Scattering of feed over the entire pond rather than conflning it to a few locations may have discouraged grass carp from feeding on pellets and contributed to the success of vegetation control.

Fifty male and 106 female largemouth bass were injected with human chorionic gonadotropin (HCG) during the 1972 and 1973 spawning seasons. Milt production was increased or maintained in 80% of the males tested. and 63% of the females ovulated. Females with spent or immature gonads did not noticeably respond to HeG injections. Females tested during the latter half of both spawning seasons demonstrated lower percentages of successful ovulations and reduced numbers of eggs per ovulation. Ninety percent of the ovulated females required only one injection, whereas nearly half of the females that resorbed their eggs required two injections before resorption could be determined. Results indicate that some females can be ovulated twice or three times with multiple injections, but that the success rate is too low to enable practical application. Most females ovulated within 48 hours of injection.

Grass carp (Clenopharyngodon idel/a) were stocked into a 3.6-ha Georgia pond devoid of vegetation to simulate conditions that might occurr in a pond where grass carp have eliminated the macrophytes. The flSh were readily captured by hook-and-line fishing. The stomachs of 417 grass carp contained primarily terrestrial macrophytes; no fish or fish eggs were found. Many of the grass carp examined weighed less than when they were stocked.

Life history data were collected from Suwannee River and Okefenokee Swamp warmouth (Lepomis gulosus) from 19 July 1968 through 28 June 1973. Suwannee River warmouth became sexually mature in the third year of life. while warmouth from the Okefenokee Swamp became sexually mature in the second year of life. Collection of fecund warmouth suggested that the nesting season extended from April to late July or early August and that peak spawning generally occurred in early May. Fecundity estimates varied from 3,029 to 22,850 ova per female and generally increased with fish length. The average total lengths of Suwannee River warmouth at ages I through VIII were 52, 73, lOS, 132, 158, 177, 189, and 214 mm, respectively. Okefenokee Swamp warmouth were 54, 90,127,154,179,179, and 190 mm at ages I through VII, respectively. The length-weight relationship of Suwannee River warmouth was log W=-5.4996+ 3.3726 Log L.

Life history data were collected from redbreast sunfish. Lepomis Quritus (Linnaeus). in the Satilla River between 1 July 1970 and 30 June 1973, Spawning was observed in the Little Satilla River during May and June at water temperatures from 22.2°-24.4°C. Strong site preference was evident. Nests were associated with fallen trees, stumps. or logs. The average nest diameter was 93.5 em and the preferred substrate was sand. Sex ratio was I male to 1.49 females. Fecundity estimates ranged from 322 to 9206 ova per female around a mean of 3302 ova. Fecundity increased with both length and weight. Average calculated total lengths at annulus I through VII were 59, 90, 125. 153. 181, 205, and 222 mm, respectively. The length-weight relationship of all redbreast examined was log W=-5.2810+3.2368 log L (r=.9759). Redbreast from the upper river were heavier per given length than specimens from the lower river.

An important element of the ichthyofauna of warmwater streams of the southeastern United States, the redbreast sunfish is the dominant species of the lower Suwannee and lower Santa Fe Rivers in Florida. Insects formed the bulk of the diet of both populations though opportunistic feeding is suggested by the wide variety of organisms tak.en. Spawning occurs from April through October, with a peak in late spring and summer. Fecundity ranged from 942 to 9968 ova per fish. Mean condition factor (K) was higher for Santa Fe redbreasts than for Suwannee specimens. Lengthwweight relationships for Santa Fe fish were log W =-4.20+2.89 (logL) and logW =-4.06+2.81 (IogL).

The food habits and growth of 1,062 largemouth bass. Microplerus salmoides (Lacepede), collected from Lake Blackshear during the period 31 March 1970-19 December 1972 were examined. Mean lengths of bass at Age I, II, III, IV, and V were 106, 253, 350, 418, and 473 mm total length, respectively. Young-od-year and yearling bass showed great variation in growth rates. Threadfin shad, Dorosoma petenense (Gunther). and gizzard shad. Dorosoma cepedianum (leSueur). were identified as the most important forage species to bass beginning their piscivorous feeding habits. The great variation in growth of young-of-year bass resulted from the timing of bass reproduction with respect to shad spawning activity. A specific goal and methods for managing largemouth bass are recommended for Lake Blackshear.

A stratified, random survey was conducted from I August 1970through 31 July 1971 at the 15 public access points on the unimpounded riverine flowing portions of the Mountain Fork River in McCurtain County, Oklahoma. The purpose of the study was to compare fisherman expenditures and capitalized resource values in the portions of the river above and below Broken Bow Reservoir, a flood control and hydroelectric impoundment. Of the estimated 16,485 fishermen who spent $156,864, 8,403 fishennen above the reservoir spent 76,757 and 8,082 fishermen below the resevoir spent $80,107. The difference was not statistically significant. Estimated expenditures at the various access sites ranged from $238 to $49,322. Mean expenditure per man-day was $9.52 for the entire river and ranged from $3.60 to $24.84 at different sites.

This study evaluated the effects of discharges from three southeastern trout hatcheries on the benthic organisms and fish in the receiving streams. The U. S. Fish and Wildlife Service hatcheries were at Suches, Georgia; Walhalla, South Carolina; and Brevard, North Carolina. Although effects differed somewhat for each hatchery, the numbers and kinds of both benthos and fish generally increased immediately downstream from the hatchery outfalls. Pollution intolerant benthic organisms were not lost from the fauna below the hatchery outfalls. No detrimental changes in the fish communities were apparent.

A 4.3 km section of Waters Creek in LumpkinCounty. Georgia. was managed for trophy trout with supplemental feeding under restrictive regulations. including 22 inch minimum size. Complete creel data for 3 years reveal a mean daily pressure of 31.9 anglers, and an annual mean catch rate of 0.18-0.24 fish/hr. Total anglers decreased 13.5% and total hours increased 18.0% 1972-1973. Trip length increased from 3.1 to 4.7 he 1972-1974. An analysis of variance of catch rate means provided evidence of differences in catch rates with total daily effort. The mean catch rate of 0.51 fish/ hr at 26-50 hr daily effort was significantly higher than catch rates at higher pressure. The cumulative frequency distribution of trophy catch rates was influenced by initial stockings. The mean standing crop (44.7 kg/hal between feeding points and high density of sub-legal fish at feeding points indicate that natural recruitment may sustain the fishery.

A trend in the stocking procedure of trout in tailwaters has developed as an outcome of increasing fishing pressure. Fingerling stocking of trout was initially recommended in tailwaters where an adequate food supply was available. and predation by predatory fish was not considered a problem. Eventually, fishing pressure increased and the fingerling trout were harvested before reaching a desirable size necessary to maintain a quality put-grow-and-take fishery. Consequently. stocking of larger catchablesize trout was resorted to; this procedure resulted in a quality put-and-take fishery. Several basic concepts pertaining to the development of trout fisheries in tailwaters were conceived after intensive investigation. The fishing pressure and harvest must first be known in order to stock trout at a proper rate and at the proper time to sustain a quality fishery.

Mean depth of capture of the white crappie in horizontal, bottom set gill nets in Arbuckle Reservoir in 1973 was not statistically different from that in this reservoir in 1974, or from that in Eufaula Reservoir (determined by collection in vertical gill nets) in 1968. The white crappie depth distribution was generally similar in these two reservoirs, and there was a seasonal cycle of distribution related primarily to changes in temperature and dissolved oxygen. Lake Arbuckle was acutely stratified by midsummer of both years, Stratification in this reservoir appeared to force white crappie into the thermocline but anoxic conditions excluded them from the hypolimnion. In Eufaula Reservoir, white crappie were distributed deeper when surface temperatures increased but their depth distribution was not limited by anoxic water. White crappie were found nearer the surface in the fall when surface water cooled.