Journal of the Southeastern Association of Fish and Wildlife Agencies

The red·cockaded woodpecker (Picoides borealis) presumably was fairly com· mon historically in the pinelands of southeastern Oklahoma. The species requires oldgrowth timber for nests and roosts, and in the past century their populations have declined due to logging operations and clearing of forestland. Remnant populations of red· cockadeds were located in the McCurtain County Wilderness Area, and on Weyerhaeuser Company lands in Pushmataha County and may still occur in Beavers Bend State Park, McCurtain County. Between 145 and 165 birds occupy 48 to 53 colonies, with 84 to 90% of the population occurring in the McCurtain County Wilderness Area. The population inhabiting the Wilderness Area is the only one in the state whose habitat and population density appear secure. Continued survival of the species in Oklahoma depends upon maintenance of old-growth pine in the Wilderness area.

In 1976-7721 attempts were made to capture wild turkeys (Meleagris gallopavo) in Michigan and North Carolina with whole corn mixed with trichloroethanol. Many attempts failed and mortality of birds captured was unacceptably high. Trichloroethanol was not recommended for use in capturing wild turkeys.

A tagging and telemetry study of translocated raccoons (Procyon lotor) was conducted during 1975, 1976 and 1977 in Kentucky. In areas of good cooperation from hunters, the reported tag return rate was 19.1% for Kentucky raccoons, 5.5% for Virginia raccoons and 1.7% for Florida raccoons. Mean dispersal distances for tagged Florida, Virginia and Kentucky raccoons was 25.7 km, 7.4 kam and 6.4 km, respectively. Twelve radiotagged Florida raccoons were monitored an average of 65 days. The probability rate of Florida raccoons released in the spring surviving until hunting season in November is less than 10%. Pen-raised raccoons moved only a few km from their release site and had a higher survival rate than Florida raccoons.

Ecological observations of gallinules on Lacassine National Wildlife Refuge from 1 April 1975 through 28 February 1976 indicate common gallinules (Gallinula chloropus) arrive earlier and begin nesting before purple gallinules (Porphyrula martinica). Eleven nests of common gallinules, characteristically positioned low in the vegetation and con· structed of bulltongue (Saggitaria lanci/olia), contained an average of 8.1 eggs. The more elevated nest of the purple gallinule contained an average of 4.5 eggs, in a sample size of 12, and was constructed primarily of maidencane (Panicum hemitomon). Common gallinule chicks form a tight cluster or grouping and follow the parent bird(s) along linear feeding paths. The more precocial purple gallinule chicks form a more dispersed aggregation around the parent(s) which feed in circular patterns. Within the first 10 days of hatching mortality may be as high as 40% for common and 30% for purple gallinules.

Wildlife scientists have been challenged for many years with the need to de· velop cost effective t.echniques for evaluating wildlife habitat. This study sought to develop such a technique utilizing LANDSAT digital imagery. The criterion on which the analysis system was based was vegetative cover diversity (VCD). In order to assess the applicability of the results of the VCD index as a measure of habitat productivity, ground·generated veg.etative and faunal diversity data were collected and compared to the VCD index. Comparisons were made for 19 plots of 65 ha each. VCD correlated positively (P < 0.05) with both plant species diversity (PSD) and faunal species diversity (FSD) for the plots ov.eralJ. This analysis indicates that the use of computer manipulated J"ANDSAT digital data is a valid technique for evaluating wildlife habitat.

The species composition and relative abundance of fishes in West Point Reservoir, a main stem Chattahoochee River reservoir, changed after impoundment in 1975. Strong year classes of gizzard shad, threadfin shad, largemouth bass, black crappie, bluegill, brown bullhead, carp, bowfin, and many sunfishes were produced in 1975. Sixteen species disappeared from the present reservoir region; 11 were not collected after impoundment, and 5 others disappeared during the first year. Forty-three species were found in the reservoir 2 years after impoundment, of which 6 did not occur in preimpoundment sampLes from the West Point Reservoir region. By 1977 the dominant species were gizzard shad, threadfin shad, bluegill, redbreast sunfish, and black crappie.

Largemouth bass (Micropterus salmoides) fail to spawn in association with dense populations of sunfish (Lepomis sp.). Previous studies have demonstrated that suppression is behavioral in nature and linked to interspecific competition for space within spawning areas. In 1976 a series of ponds were stocked with 3 pairs of bass and densities of sunfish from 0-458 kgJha to determine the density necessary to effect suppression. Results were inconclusive with spawning occurring in all ponds but only late in the season in ponds stocked at 250 kgJha or above. It was not clear whether the growth of aquatic vegetation or cropping of the sunfish population resulted in spawning in these ponds. In 1977 a second series of paired ponds (1 with vegetation, 1 without) were stocked with 3 pairs of bass and sunfish at densities of 0-448 kgJha.

Simazine (2-chloro·4, 6-bis (ethylamino)-s - triazine) applied at a rate of 11.2 kg/ha as a preflooding treatment of striped bass (Morone saxatilisWalbaum) rearing ponds effectively controlled aquatic weed growth for periods of up to 172 days. In untreated ponds, weed species were dominant in 9 of 16 replications (56%). Where simazine at a rate of 11.2-14.0 kg/ha was applied to the pond bottom just before flooding, only 3 of 17 replicates (18%) supported nuisance aquatic plant species. Survival and growth of striped bass fry and fingerlings was as good or better in the treated ponds as in the untreated ones.

Information relative to control of problematical clam shrimp (EubranchiopodaConchostraca) with Masoten (Dylox) was accumulated over a 10. yr period at several Southwestern hatcheries. Laboratory and field studies showed that control could be achieved with single applications of Masoten as low as 0.01 mgl (active ingredient). No deleterious effects on fry, fingerlings, or adult fish of several species were noted. Decomposition of the chemical, as well as effects on plankton and bottom fauna, are discussed. The paper places on record the efficacy of Masoten against clam shrimp, a level of treatment for same, and a suggested approach to control.

A biological testing program was conducted during 1974·75 to determine the efficiency of an air·bubble curtain in reducing fish impingement at Arkansas Nuclear·One Unit I, on Dardanelle Reservoir, AR. Air curtain operation did not effectively deter fish from entering the intake canal or substantially reduce impingement. Seasonal varia· tions in species composition and length·frequency distribution of impinged fish were independent of air curtain operation. There was a significant inverse correlation between water temperature and impingement levels during fall 1974 and spring 1975. Highest impingement rates occurred during late fall, winter, and early spring, regardless of air curtain status. Impinged individuals were predominantly young-of-the·year-fish, especially threadfin (DoTOsoma petenense) and gizzard shad (D. cepedianum), assumed to be thermally stressed by low « 15.5 C) water temperatures.

Specific swimming speeds (L sec-1 ) of spotted seatrout (Cynoscion nebulosus) were linearly related (S = -0.16+0.93X) to tail·beats/sec (x) over speeds ranging from about 1.5 - 4.0 length/sec. Maximum sustained swimming speeds were measured at salinities ranging from 10 to 45 ppt in intervals of 5 ppt. At about 20 to 25 ppt, maximum sustained swimming speeds were close to 4 lengths/sec, but performance was reduced at salinities above or below this range. At 45 ppt, maximum sustained speeds were only about 2 lengths/sec. These results indicate that maximum sustained swimming perform3. p.ce can provide an effective method for evaluating salinity stresses.

Present taxonomic status permits discussion of larvae of vermilion snapper (Rhomboplites aurorubens), other snappers combined (Lutjanidae), and all groupers com· bined (Serranidae, subfamily Epinephelinae). Larvae of these groups together comprise less than 1% of the total larval fish catch from neuston and bongo samplers in shelf waters of the South Atlantic Bight. Larvae of groupers and snappers are most abundant in spring and in summer respectively. Larvae are distributed in outer shelf and upper slope waters, where current is northerly. Northerly current may predominate in affecting larval drift (in which case populations may primarily be recruited from the Caribbean 01' Gulf of Mexico) or a significant proportion of larvae spawned in the Bight may be retained by currents throughout development to settling.

Epistylis infestations occurred on 16 of 32 fish species collected from Mountain Island Lake and Lake Norman, North Carolina, during 1974 and 1975. Percichythids, centrarchids, and ictalurids were the fishes most commonly infested, while infestations were rare on clupeids, cyprinids, and percids. Epistylis was generally more prevalent on fishes during fall (September through November). Percichthyids, followed by centrarchids, had the highest intensity of infestation. Intensity of infestation increased with surface area and length of percichthyids, but not with that of centrarchids. Although the attachment site varied among fish species, Epistylis infestations were restricted primarily to the bony parts. The prevalence of Epistylis on fishes did not correlate with the abundance of Epistylis in the plankton.

Weekly samples of river shrimp (Macrobrachium ohione) were collected from the commercial bait fishery located at Port Allen, Louisiana. Mean size was 30.6 ± 0.2 mm (total length) (n = 7,058); the mode was 27 mm (n = 851); and the range was 17-92 mm. Mean size declined from approximately 39 mm in early March (when fishing began) to approximately 28 mm in mid-August (when fishing ended). The mean size of ovigerous females was 66.1 ± 1.7 mm (n = 88); and the range was 27-92 mm. Bopyrid parasitization is discussed. A comparison is made with data collected from the same area in the early 1930's prior to extensive industrialization.

A sonar fish counter installed at the Pinopolis Dam navigation lock near Moncks Corner, South Carolina in 1975 was used during the last 3 springs to enumerate blueback herring (Alosa aestivalis Mitchill) passing into the Santee-Cooper Lakes. Construction of the biomass fish counter was based on the design of salmon smolt counters used successfully in Alaska. Characteristics of fish movement and schooling patterns were determined and their relationship to accurate counting of herring was evaluated. Initial tests to prove the accuracy of counts were not successful. However, other population indices indicated that trends were accurately assessed.

Sustained voluntary swimming speeds of 5 species of juvenile estuarine fish were determined in a laboratory circular flume, 2.5 m in mean circumference. Successful tests depended on the fish's ability to avoid downstream displacement through positive rheotaxis. The following swimming speeds, in body lengths (BLjsec, were measured: 3 to 6 em Atlantic menhaden (Brcvoortia tyrannus), the species of primary interest, swam 5 (at 13 C) to 11 (at 30 C) BLjsec; striped mullet (Mugil cephalus), 3 em, swam 8 (at 15 C) to 12 (at 25 C) BLjsec; pinfish (Lagodon rhomboides), 4 em, swam 11 BLjsec (27 C); spot (Leiostomus xanthurus), 4 em, swam 6 BLjsec (25 C); Atlantic croaker (Micropogon undulatus), 7 em, swam 5 BLjsec (30 C). An evaluation of the apparatus and implications of the data for predicting impingement of juveniles on power plant intake screens are included.

Techniques have been developed for spawning adult southern flounder. (Paralichthys lethostigma), spotted seatrout (Lynoscion nebulosus), and red drum (Setaenops ocellata) and rearing their larvae for freshwater acclimation and introduction into heated freshwater reservoirs in Texas. Egg production, percentage egg fertilization, percentage hatch, percentage return of larvae stocked into laboratory aquaria and hatchery ponds, and potential for fingerling survival in fresh water were compared for the 3 species. Red drum was found to be the most suitable for culture and introduction into fresh water. A diagram and estimated construction cost of a laboratory facility for holding and spawning marine fishes is presented.

Prey selection by sauger (Stizostedion canadense) was monitored from November 1976 through April 1977 in the portion of Watts Bar Reservoir, Tennessee, near the Kingston Steam Plant. Threadfin shad (Dorsoma petenense) provided the entire forage base for sauger until the population of threadfin was almost completely eliminated by low temperatures in December and January. Some sauger switched to alternate prey, but food consumption was greatly reduced in February-March as > 75% of stomachs were empty. Food consumption of sauger smaller than 30 em was restricted earlier in the year by the lack of threadfin less than 8.0 em. Digestive rate studies in the laboratory indicated digestion continued at a reduced, but effective, rate at temperatures < 10 C.

Scales from blue tilapia (Tilapia aurea) captured in gillnets indicated that annulus formation occurred primarily in March and April in 1973 and 1974, but in April and May 1975,. Average back-calculated total lengths of males were 197 and 258 mm at Age I and II and for females 183 and 248 mm. Total population of blue tilapia in December 1974 was estimated as 4,856,963. Of this total 3,120,810 were Age 0 and 1,591,823 were Age I. Biomass of the tilapia population was estimated to be 799,978 kg or 2,640 kg/ha. Survival of blue tilapia from Age I to II was calculated to be 7%. From these estimates the potential yield of harvestable blue tilapia would be 1,629,501 fish weighing 521,153 kg.

Copper sulfate was evaluated as a potential control for parasitic fungal infestations on largemouth bass (Micropterus salmoides) and striped bass (Morone saxatilis). Treatments were planned to reduce the incidence of free-swimming zoospores of the fungi. Largemouth bass fingerlings (15-20 cm T.L.) were stocked in 0.04 ha ponds and given multiple treatments of copper sulfate at 0.5; 1.0 or 2.0 ppm or Dimethylamine salt of 2,4-Dichlorophenoxy (acetic acid) at 2.0 ppm. Chemical treatments were made on the day before stocking and at regular' intervals thereafter for 6 treatments. Survival rates of largemouth bass treated with copper sulfate were 96, 91.7 and 100'70 at concentrations of 0,5,; 1.0 and 2.0 ppm respectively; only 10.7% of the controls survived. No significant difference of survival rate between control and 2,4-D treated fish was noted. Striped bass adults were treated with multiple copper sulfate treaments a 1.0 ppm after being captured in gill nets.

The need to suspend newly hatched striped bass (Marone saxatilis) larvae until swim-up prompted comparison of holding techniques. Fingerling returns were tabulated over a 3 yr period from fry held in aquaria vs. returns from fry held in Saran cages in rearing ponds. Mean production for a 3 yr period from ponds stocked with fry held in cages was better overall than other methods. The success of holding cages resulted in a substantial saving in manpower as constant care of fry was not needed. The cage holding method is only I of many facets of striped bass rearing and is only a contributing factor to high production, not a critical factor such as the quantity and quality of food available. This technique would apply to those situations where unsuitable temperature, turbidity or limited facilities make the tank or aquaria method impractical.

A simple recurrence model is developed for the prediction of DDT flux through Atlantic menhaden (Brevoortia tyrannus). The DDT body burden in young-of-the-year menhaden at any time is equal to the body burden on the previous day plus the DDT accumulated on the current day minus the DDT turnover. Accumulation of DDT is simulated and compared with field observations. Estimations of DDT ingestion, assimilation, turnover, and egestion are made on both per fish and population bases. It is estimated that emigrating juvenile menhaden export 20 g DDT year -, from the Newport River estuary in North Carolina.

In the Dixon Springs area of the Cumberland River, Tennessee, larval Lepomis spp. began feeding upon crustacean zooplankton, especially Bosmina longirostris, when the fish attained lengths of 6.7 mm in 1975 and 8.8 mm in 1974. Cladooerans remained the dominant food item throughout the larval stage. The fish food selection diversified [to include other taxa.] larva reached approximately n.5 mm. At greater lengths, Lepomis spp larvae and postlarvae begin to rely more on chironomid larvae.

Laboratory spawning and larval rearing studies were conducted with red drum (Scianenops ocellata) and southern flounder (Paralichthys lethostigma) from 1974 through 1977. Adult fish were placed in 29.92 kl spawning tanks equipped with biological filters and subjected to photoperiods and temperatures regulated to simulate seasonal variations. Red drum spawned 52 times producing 6.0 X 107 eggs. Southern flounder spawned 13 times producing 1.2 X 105 eggs. Eggs were collected and incubated, and larvae were reared to fingerling size. This paper describes techniques used to produce fingerling red drum and southern flounder.

The effects of Masoten, an organophosphate parasiticide, on phytoplankton and zooplankton in earthen ponds were studied. In 2 separate trials, 3 ponds (0.04 hal received a single application of Masoten at a rate of 0.25 mg/l (active ingredient) and 3 ponds served as untreated controls. Net plankton samples were collected at pretreatment, and 5, 24 and 48 hI's following treatment. Toxic effects were based on quantitative.qualitative plankton analyses. Phytoplankton and rotifers were unaffected by treatment. The copepod Diaptomus sp. and nauplii were also unaffected. However, variability in response of copepods and nauplii to Masoten can be anticipated. Cladocerans were the most sensitive to Masoten; losses are to be expected when the compound is employed for control purposes. Information regarding residues and decomposition of Masoten is presented.

Jocassee Reservoir (3,063 ha) is the upper pool for a 61O·MW pumped storage hydroelectric plant in northwestern South Carolina. Trout (200-225 mm long) have been stocked annually since 1972. The volume of trout habitat during summer has decreased annually from 1973 to 1976, and is associated with increases in the temperature and volume of water pumped from the lower reservoir. The top of the thermocline during September was lowered from about 9 m in 1973 to nearly 19 m in 1976, and trout habitat was reduced by about 65%. On the basis of a regression presented, we predict that trout habitat will be reduced to nil when plant operation reaches 63% of capacity (perhaps by 1981).

This study was conducted to determine if water temperature increases during the walleye (Stizostedion vitreum vitreum) spawning period reduced egg hatch rate and if water temperature manipulation during egg fertilization would increase hatch rate. Walleye eggs were subjected, before and during fertilization, to 1 of 3 treatments involving water temperatures above and below 12 C. Water temperatures above 12 C were found to reduce hatch rates. Stripping and fertilizing eggs collected from reservoir water temperatures above 12 C into water chilled to 7.2 C significantly increased hatch rates. Use of this technique could improve walleye culture and management operations in some southern regions.

This study investigated possible factors inhibiting spawning of largemouth bass (Micropterus salmoides) in Victor Braunig Lake, a 547 ha power plant cooling reservoir in Bexar County, TX. Data on water quality, fish communities, pesticide and heavy metal concentrations and largemouth bass blood components and sexual development were analyzed from Braunig Lake and Calaveras Lake, a similar power plant lake nearby. All factors were similar between the 2 lakes. Largemouth bass from Braunig Lake began spawning 2 days after being moved to hatchery ponds. Largemouth bass from Calaveras Lake which had a normally reproducing popUlation failed to spawn in pens in Braunig Lake. Braunig Lake largemouth bass had no chronic abnormalities that would inhibit spawning. Fertilized largemouth bass eggs collected from a private lake hatched in Braunig Lake water and healthy fry were produced. Largemouth bass fry collected from the same lake also survived and healthy fingerlings were produced.

Midwater artificial structures were placed in a freshwater reservioir to determine if fish would associate with these structures. SCUBA observations were used to evaluate the effectiveness of the structures. Alabama spotted bass (Micropterus punctulatus henshalli) and bluegill sunfish (Lepomis macrochirus) were attracted to structures suspended over water depths up to 33 m and as far as 250 m from the shoreline. Behavioral observations of fish on structures and the development and subsequent association of spotted bass fry spawned on a structure are discussed.

Channel catfish (Ictalurus punctatus) were stocked at rates of 250, 500, 1,000 and 2,000 fry /208 1 drum, and reared to fingerling size. No significant differences occurred in rate of gain from days 0-33, but gains ranged from 0.22 g/day at the 250 stocking rate to 0.08 g/day at the 2,000 stocking rate from days 0-70. The highest average total biomass of 10,095 g was reached at the 2,000 stocking rate. Flow rate was maintained at a constant 0.32 I/sec in all drums. Food conversion from days 17-70 ranged from 1.42 at the 250 stocking rate to 2.67 at the 2,000 stocking rate. Water quality was monitored to evaluate the effect on growth. Oxygen concentration became a critical limiting factor as total biomass increased. Growth rates were best at the lower stocking rates in which the oxygen concentrations were higher.

Supplemental stocking of fingerling and intermediate size largemouth bass (Mieropterus salmoides) did not provide substantial control of forage fish populations; however, stocking fingerling bass may have improved year class strength in those years they were stocked. Although loss of stocked intermediate-size bass over the spillway was negligible, those fish were vulnerable to angling. A measured rate of fishing (F = 0.08) was exerted on a population of bass estimated at 22.3 harvestable bass/ha weighing 34 kg/ha.

The quantity, quality, and timing of freshwater inflows to the San Antonio bay system are recognized as major factors in fishery production. A methodology has been developed using commercial fishery statistics and gaged inflow records to analyze the fishery dynamics and its relation to freshwater inflows from the contributing river basins. Statistical correlation analysis and assessment of "best" versus "worst" years of production were employed to evaluate the effects of year to year fluctuations in freshwater inflows. Although somewhat rudimentary, the results of the analyses are clear enough to be of practical value for future water resources planning and management. an inflow regime, with a monthly distribution of 1.48 x 10' total annual ha-m of freshwater, is presented that could meet the minimum sustaining requirements of the estuary's fisheries.

The tailwater fisheries of Lake of the Ozarks and Pomme de Terre Lake were measured by a part-time roving creel survey from 1965 through 1974. Catch rates of fishes were compared with temperature, conductivity and dissolved oxygen, but no significant correlations were found. However, high positive correlations existed at Lake of the Ozarks tailwater between annual average catch rates and the annual average discharge of water, and also between preceding mean monthly discharges and following monthly catch rates. There was also a high positive correlation between estimated number of fishes caught in this tailwater and the number of days per year that the flood gates were open. At Pomme de Terre tailwater, there was a high positive correlation between discharge and catch rate for monthly, seasonal, and annual periods.

Channel catfish (Ictalurus punctatus), were reared in 1.0 m' cages suspended in the intake canal of a cooling reservoir. Effects of density were tested by stocking cages in replicates of 4 at densities ranging from 500 to 900 fish in increments of 25 individuals. There was a significant increase in net production and variation in length and a signifi· cant decrease in feed efficiency, mean fish weight, and percentage of harvestable-size fish as stocking density increased. Survival was not affected by number of fish per cage.

Quantitative samples of fish were obtained from warm-water streams with detonating cord. Preliminary results indicate this explosive is an effective tool for fish sampling in streams. Numbers of fish collected per kilometer of stream ranged seasonally from 200 to 473.

The relationships of abundance of brown shrimp (Penaeus azteeus Ives) and white shrimp (P. setiferus L.) to spring and fall river flow into San Antonio Bay, Texas were studied. Standing crop indices determined from trawl sampling and bay commercial landings were poorly correlated; only those indices obtained from trawl samples were deemed valid. Brown shrimp abundance showed no detectable relationship to changes in freshwater inflow; white shrimp abundance, however, showed a significant positive correlation with May-June inflow and with the previous year's September-October inflow.

Length at maturity computed for female flathead catfish (Pylodietus olivaris) from marshes of southwest Louisiana was 589 mm. Empirical data showed males approach maturity in the 390-439 mm size range. The length-weight regression for flathead catfish was best described by: Log W = -8.9640 + 3.3732 Log L, where W = weight in kg and L = length in mm, r = 0.97. The computed total length-collarbone length conversion equation for flathead catfish was Y = 10.3428 + 0.7251, where Y = total collarbone length in mm and X = total body length in mm, r = 0.99. Dressout-live weight relationship for flathead catfish was Y = 0.3308 + 0.7123 X, where Y = cleaned ( headed and eviscerated) weight in kg and X = live weight in kg, r = 0.70. Computed length at maturity for blue catfish (letalurus fureatus) was 481 mm.

A total of 259 sauger (Stizostedion canadense) was tagged and released downstream of Bull Run Steam Plant during the winters of 1974-75 and 1976. Gill nets and electrofishing gear were used to recapture sauger that moved into the discharge basin or past the plant. Over the study period 7 sauger were recaptured upstream from the discharge; 3 of these had moved past the plant while it was continuously operating. Fourteen sauger were caught in the discharge. The thermal plume from Bull Run Steam Plant had no significant effect on the movement of sauger.

Creel surveys were conducted at TVA's Gallatin, Kingston, and John Sevier Steam Plant discharge basins from March 1975 through May 1976. The highest period of angler use at all plants occurred between April and June. Peak harvest and pressure in the 3 discharge basins were significantly related, and high periods usually occurred later in the year than has been reported from other areas. At least 18 species were found in the combined creel from the 3 plants, and species diversity was greatest during the warm months. Three species, channel catfish (lctalurus punctatus), bluegill (Lepomis macrochirus), and white bass (Morone chrysops), comprised over 50% of the combined creel. Angler harvest remained uncommonly high from March through August with lowest levels observed in the winter months. The overall angler catch per hour (c/h) was 0.5 fish while the highest monthly c/h recorded was 2.3 at John Sevier in May 1975.

Distribution of fish in the heavily impounded Tennessee and Cumberland River systems shows definite longitudinal zonation similar to that in nonimpounded river systems. Ten of 11 physical variables examined were highly correlated with one another, reflecting the complex of conditions accompanying changes from storage reservoirs in upper elevations to mainstream reservoirs in the lowlands. Elevation was the variable most highly correlated with the number of species. Cluster analysis indicated 4 associations of reservoirs: lower mainstream, upper mainstream and large storage, upper Holston, and Blue Ridge.

A graphical method of illustrating dominance in fish communities is presented. This procedure incorporates both numeric abundance and frequency of occurrence data and illustrates the relative dominance of each species.

The fishery for rainbow trout (Salmo gairdneri) in the Bull Shoals tailwater has developed as a seasonal boat fishery which in peak years provides more than 250,000 angler days of fishing, and a catch of more than 750,000 trout. Use was concentrated along the upstream one-third (48 km) of the tailwater in 1971-73, where about 60 percent ot the total fisherman effort, 50 percent of the catch, and 75 peroent of the total guided fishing occurred. Since many anglers traveled long distances, rented boats and motors, and employed guides to fish the tailwater, the economic value of the fishery was high. As in most fisheries in cold tailwaters in the South, erratic patterns of water release strongly influenced fisherman use and harvest. During 1971 and 1972, y,ears of below average water release, fishermen caught about 95 percent of the trout stocked.

Larval spotted seatrout (Cymoscion nebulosus) grew faster on 1 and 2 day prefed brine shrimp (Artemia salina) nauplii than fish fed newly-hatched nauplii. Fish growth and survival were reduced when 3 and 4 day pref.ed, as compared with newlyhatched nauplii were offered. Proximate analysis and calorimetry demonstrated the occurrence of a temporal decline in the nutritional value of both fed and unfed brine shrimp nauplii. At the relatively low levels of algal cell concentration available for prefeeding brine shrimp, this study indicates that I day old unfed nauplii are nutritionally equal to algae prefed nauplii as a food source for larval spotted seatrout. One day old brine shrimp nauplii are a better food organism for larval spotted seatrout 12 to 21 days of age than newly-hatched nauplii because of the larger size of the former.

The diets of r,edbreast sunfish (Lepomis auritus) and spotted sucker (Minytrema melanops) in the Satilla River, Georgia, were shown to be quantitatively different using Spearman rank correlation coefficients. The index of overlap of Pianka by number and weight showed considerable overlap in the diet during the fall. Chironomids were the main food component contributing to this overlap. The index of electivity of Ivlev indicated moderate to high selectivity by both species for chironomids in the winter, spring, and summer and some selectivity in the fall. The diet overlap between the 2 species was not considered to be a problem.

Methandrostenolone was not effective in promoting growth in channel catfish (Ictalurus punctatus) at the 2.5 mg/kg of body weight/day dosage level. There were no significant differences (.05 level) in treated and untreated fish with respect to total weight gain, percent crude protein, and moisture content of the Hesh. No differences were observed in gross morphology, liver to body weight ratios, or microscopic examination of liver sections. However, after approximately 3 to 4 wks in a distilled water bath, the hemotoxylin/eosin stain had cleared only from liver sections of the catfish receiving the steroid.

We monitored fish populations in a southwest Florida cypress (Taxodium distichum) strand system through an annual wet season-dry season cycle. Populations increased from zero when the site was inundated to densities of 3-8 fish m2 and biomass of .3-.4 g/m2 in late wet season. Two months after drydown began, fish became concentrated. In wet prairie and "pond" cypress habitats concentration continued until the sites went dry, but "bald" cypress populations reached high densities early, then stabilized until just prior to complete drydown, when they decreased drastically. Wet season populations were probably controlled by hydrologic factors, but predation was important in determining dry season density, biomass, and species composition.

Individual heat resistance times were determined in 180 min experiments during June 1974 through September 1975 for 8 species of crustaceans and 47 fishes taken directly from the intake canal of the P. H. Robinson Generating Station, Bacliff, Texas. Indi· vidual r,esistance times increased with an increase in capture temperature and with a decrease in test temperature. June-September is the most thermally critical period of the year for animals transported by the power plant from intake water and exposed to hot discharge effluent. During the rest of the year, nearly all organisms survived 3 h at temperatures higher than average discharge canal temperature.

This paper outlines procedures used in obtaining approval of a management program. After intense inter-division communication and cooperation, field personnel of the Fisheries, Law Enforcement, and Information-Education Divisions of the Florida Game and Fresh Water Fish Commission presented an outline ofthis controversial plan to respective division chiefs for review and refinement. The program was presented to the Florida Game and Fresh Water Fish Commission by the supervisory staff for approval. Local civic, conservation, and governmental bodies were contacted by field level personnel to provide general concepts ofthe program. Public meetings were held to assess public reaction to the plan. After economic analysis indicated feasibility of the program, enabling legislation was obtained to provide funds and additional personnel to supervise the program.