Journal of the Southeastern Association of Fish and Wildlife Agencies

The Conservation Monitor was a telephone survey of 854 Missourians first conducted in 1994 by the Gallup Organization for the Missouri Department of Conservation (MDC). Objectives were to assess Missourians' opinions on the state's environment, MDC's performance, and conservation issues. Results revealed high satisfaction among Missourians with the care given their state's fish, forests, and wildlife, and more generally with the care given Missouri's natural environment. However, 28% did not know or were incorrect about MDC's responsibilities, and 40% were unable to suggest one thing the agency might do better. Missourians thought a much larger portion of the state is in public ownership than is true and perhaps assume that state and federal resource agencies in Missouri are in a stronger position to influence land management than is the case.

Small watershed impoundments provide the principal recreational fishing opportunities within national forests in Mississippi. Relative abundance and stock structure of bluegiii (Lepomis macrochirus) and largemouth bass (Micropterus salmoides) were assessed by electrofishing 18 national forest impoundments during spring 1990, autumn 1990, and spring 1991. There were no significant yearto- year or seasonal differences in catch per unit effort (CPUE) or proportional stock density (PSD) for either species. Mean CPUE for stock-size largemouth bass (total length ≥ 200 mm) ranged from 8.2 to 9.7 fish/hour of electrofishing and mean PSD ranged from 14.0 to 22.5. Mean CPUE for stock-size bluegill (total length ≥80 mm) ranged from 38.7 to 45.0 fish/hour and mean PSD ranged from 21.5 to 21.8. Twenty-five habitat, accessibility, and watershed variables were evaluated by multiple regression techniques to determine factors that significantly described largemouth bass and bluegiii CPUE and PSD.

During spring and summer 1986, a massive disease-caused fish kill occurred on Lake Walter F. George, Georgia, which resulted in significant and longlasting changes in the fish populations of this reservoir. Prior to the fish kill, populations of both threadfin (Dowsoma petenense) and gizzard shad (D. cepedianum) were dominated by intermediate- and harvestable-size fish. Anglers reported largemouth bass (Micropterus salmoides) fishing was poor, and age analysis indicated poor recruitment for several years. Following the fish kill, shad populations were dominated by large numbers of fingerlings, and standing crops of intermediateand harvestable-size shad were much reduced. Large numbers of largemouth bass were recruited to the fishery the year following the fish kill, and recruitment remained good for 8 of the 9 years following the kill.

We surveyed the extent and availability of fisheries data from major (>200 ha) impoundments in 2 southeastern U. S. drainage basins, the Apalachicola- Chattahoochee-Flint and Alabama-Coosa-Tallapoosa, both located primarily in the states of Georgia and Alabama. Data were used to generate regression models relating fish reproductive success to hydrologic variables. Results were used to define relationships between reservoir operations and abundance of young fishes. Of the 25 major mainstream and storage reservoirs in the 2 systems, 4 had sufficient historical data for fisheries and hydrologic variables to allow statistical analyses. Species of concern were black bass (largemouth bass, Micropterus salmoides and spotted bass, M. punctulatus), as they were abundant in both systems and have served as indicator species in similar studies in other basins.

The management objective at Caney Creek Reservoir, a Louisiana lake impounded in 1986, was to produce trophy-size largemouth bass (Micropterus salmoides). Management actions included introduction of Florida bass (M s. floridanus), supplemental forage stocking, and initiation of length limit regulations. Prior to impoundment, the reservoir basin contained northern largemouth bass (M. s. salmoides) and intergrades between the northern and Florida subspecies. Eight years after the initial stocking of Florida bass in 1986, 49% of the population were northern bass, 23% were Florida bass, and 28% were intergrades. Relative abundance of bass fry and fingerlings was higher during the first 4 years of impoundment than reported for similar new lakes in Louisiana. Forage availability declined for bass <305 mm by 1988, 2 years after impoundment. Mean relative weight (Wr) of bass 203-305 mm declined to 86 by 1989; bass >305 mm had a mean Wr of 96.

One component in evaluating the need for or the result of a fishing regulation is an angler survey. In recent years, efforts have advanced the way an individual survey is designed, conducted, and analyzed. However, managing approximately 30-40 on-site angler surveys each year led Missouri to develop and implement stringent data processing guidelines. These guidelines ensure survey objectives are addressed; appropriate survey methodologies are used; clerks are properly trained; survey forms, questions, and coding are standardized; and data entry and analysis results are completed in a timely manner. The standardization techniques used in Missouri and the improvements generated as a result of these guidelines are discussed.

Percent return, survival, and harvest rates of stocked rainbow trout (Oncorhynchus mykiss) were evaluated in 3 Tennessee streams from 1991 through 1994. Harvestable-size trout were stocked 2-4 times during spring at densities of 29-188/km. Subharvestable (fingerling) trout were stocked only during fall at densities of 69-286/km. Mean annual returns ranged from 13% to 29% over the 4 years of the study and averaged 23% for all 3 streams. Returns for fall-stocked trout were negligible. Survival of spring-stocked (March-May) trout was low, ranging from 2% to 7% by July of each year. Similarly, survival of fall-stocked trout was also low and ranged from 1% to 3% by the following March. No significant relationship (P > 0.05) was detected between stocking densities and mean harvest rates or percent returns of individual stockings. Thus, altering stocking densities and periods did not achieve a greater return to the angler in these streams.

Human chorionic gonadotropin (HCG) is often used to induce spawning offish. However, the U.S. Food and Drug Administration has not approved HCG for use in fish because they claim additional efficacy data are required. Efficacy of HCG for spawning striped bass (Morone saxatilis) and white bass (M. chrysops) was evaluated at 15 hatcheries in 10 states. For strip spawning of females, a single dose of HCG was effective for 90.2% of striped bass (N = 428) and 89.4% of white bass (N = 660). After strip spawning, hatching rates were 39.5% for striped bass and 26.1% for white bass. Of 90 striped bass and 70 white bass females injected with saline, none ovulated. Milt was obtained from all striped bass males (N = 325) and from 98.8% of white bass (TV = 862) males injected with HCG. Of 47 striped bass and 24 white bass males injected with saline as controls for the stripping technique, only 63.8% of striped bass and 37.5% of white bass produced milt.

White bass (Morone chrysops) were reared to maturity and spawned in 2 consecutive years to evaluate their hatchery performance and potential for reuse. Egg production and hatching could not be statistically compared between 2- and 3-year-old fish due to estimation of size data and pooling of hatch data in 1994. Three-year-old virgin females had a mean production of 81,413 larvae/kg body weight and an egg hatching level of 62.9%. No statistical differences (P ≤ 0.05) in latency, egg and fry production, or hatching were detected between 3-year-old virgin and previously strip-spawned fish. Hatchery performance data for domesticated white bass were similar or greater than the information available on similarsize wild white bass. Our results suggest that domesticated white bass may be a suitable substitute for wild fish currently used in hatchery operations.

A winter drawdown was evaluated to control waterhyacinth (Eichhornia crassipes) in B. A. Steinhagen Reservoir in southeast Texas. A 1.8-m drop in water level was initiated on 15 December 1993 and maintained through 17 February 1994. Freezing temperatures were recorded on 19 days during the drawdown with the lowest temperature —6.7 C. A significant (P < 0.0001) reduction in waterhyacinth frequency of occurrence was indicated in line transects. Waterhyacinth areal coverage was reduced from 1,476 ha in June 1993 to 26 ha in June 1994.

The existence of a distinct walleye (Stizostedion vitreum) population in south-flowing drainages of the southeastern United States has been suspected for some time. Recently, a mitochondrial-DNA (mtDNA) marker was identified that permitted discrimination of these southern walleyes from northern forms. In order to determine the type and distribution of walleyes in Alabama, mtDNA analysis was conducted on 35 individuals collected from 3 river systems within the state. Thirty-one fish collected in the Mobile Basin were the southern form of walleye, which previously had been identified only in northeastern Mississippi, while 4 fish from the Tennessee River were of the northern form. There was no evidence for the successful establishment of any female walleyes from Ohio that were stocked into 2 impoundments in the Mobile Basin 10-20 years ago.

Genetically-marked strains of walleye (Stizostedion vitreum vitreuni) from Arkansas (ARS) and Iowa (IAS) were stocked simultaneously into a Texas reservoir in 1985 to evaluate strain-related performance differences associated with spawning and growth. Post-stocking collections made during the spring spawning season (1988-1990) resulted in the capture of 132 walleyes from this year class. ARS walleyes comprised 35% of 1985 year-class samples which was significantly higher than the stocking proportion (26%). Differences were attributed to ARS females being more abundant than IAS females in samples. This unexpectedly high abundance of ARS walleye was not considered an indication of higher survival but merely evidence of temporal differences in movement of females of each strain to spawning grounds. This hypothesis was supported by strain-related sex ratio differences identified in samples; ARS ratios favored females whereas IAS ratios favored males.

Fish biomass and angler harvest data were collected from Keowee Reservoir during a period when thermal characteristics of this reservoir were significantly altered by operation of a large steam-electric power plant. Plant operation increased the heat load of the reservoir and depressed the depth of the thermocline. During the 22-year sampling period, fish biomass (primarily for nonsportfish taxa) declined, fishing effort increased, and angler harvest rates remained unchanged.

Fish standing crop data from rotenone surveys of 43 Louisiana lakes from 1969 to 1989 were analyzed in an effort to classify them for fisheries management purposes. Total fish, largemouth bass (Micropterus salmoides), and >30-cm largemouth bass standing crops averaged 207.7, 11.8, and 7.7 kg/ha, respectively. Results from these rotenone surveys were compared to those of similar studies in the 1950s when Louisiana lakes were placed into habitat categories. Standing crops were compared to various water-quality parameters; they were positively correlated to chlorophyll-a levels. Standing crops of fish were affected by the location of the lake within land resource areas in Louisiana. Higher fish biomass occurred more often in lakes associated with the fertile soils of the Southern Mississippi Valley Alluvium than with the Southern Coastal Plain region of the state.

Fish habitat of the Edisto River Basin in South Carolina was evaluated using a geographic information system (GIS). A committee of fisheries biologists was formed to evaluate fish habitat within the Basin, and the GIS was used to compile and analyze data and generate maps to represent quality of fish habitat. United States Geological Survey (USGS) 1:24,000-scale digital line graph (DLG) hydrography data were assigned values for data on species composition, predesignated protected areas, riparian habitat, dams and impoundments, ditches and channelization, and water quality. Criteria were developed to evaluate fish habitat in the Basin. Each criteria was assigned a point value, and these values were totaled and subdivided into Value Classes 1, 2, and 3 representing high, moderate, and low quality fish habitat, respectively. Value Class 1 consisted of 92% of the main river reaches and the entire estuarine portion of the Basin.

Scales and otoliths from largemouth bass (Micropterus salmoides) of known ages (age 6, 7, and 8) were prepared and examined by 3 experienced readers who were uninformed of specimen age or length. Results indicated limited agreement between readers and numerous inaccurate age estimations. Among 97 scale samples read, all 3 readers only agreed on the age of a single specimen which was older than estimated; using otoliths, readers agreed on 4 specimens which were correctly aged. Percentage of correctly-aged fish ranged from 10% to 30% with scales and 39% to 47% with otoliths. Percent of fish correctly aged ± 1 year ranged from 29% to 77% with scales and 78% to 98% with otoliths. Backcalculated lengths-at-age based on scale annulus measurements made by a fourth reader who knew specimen age, length, and sex were typically less than actual measurements taken each year (in October) with the greatest differences for earlier years of life.

Age, growth and mortality of lane snapper {Lutjanus synagris) from the northern Gulf of Mexico (Port Aransas, Texas, to Panama City, Fla.) were examined. Otolith sections from 694 fish collected from January 1991 to December 1994 were used to develop growth information using 2 methods (direct proportion and regression) of back-calculation. Fish ranged in age from 2 to 17 years and their size ranged from 210 to 673 mm total length. Males grew slightly faster and were larger at age than females; however, the oldest (age 17 at 500 mm) and largest (673 mm at age 11) were females. Full recruitment to the recreational fishery was at age 4-5. Estimated instantaneous total mortality (Z) ranged from 0.3750 to 0.5767. Natural mortality (M) ranged from 0.1125 to 0.2388.

A total of 139 grass carp (Ctenopharyngodon idella) of unknown ploidy were collected by bowfishing during 1993 and 1994 in Lake Guntersville, Alabama. Ages were determined from sectioned otoliths (lapilli), then age-specific total lengths were back-calculated using scales of known age. Mean back-calculated total lengths of grass carp were 334, 627, 768, 852, 896, 895, 920, 965, and 973 mm at ages 1 through 9, respectively. A length-to-weight relationship was calculated as: weight (g) = 0.00000519 x total length mm3-14, r2 = 0.92. A von Bertalanffy growth equation described growth as: Lt = 954 (i-e-0.590(t-0.257)), r2 = 0.99. Growth averaged 2.33 kg/year through age 4; subsequent growth was much slower, averaging 0.71 kg/year. Growth in Lake Guntersville was slower and more variable than in the Santee Cooper reservoirs, South Carolina. Occurrence of 3 age classes not stocked by Tennessee Valley Authority (TVA) precluded mortality estimates.

The performance of 3 seines was evaluated in 6 state-owned public fishing lakes in Alabama. The catch of bluegill fry (Lepomis macrochirus) and young of year (YOY) largemouth bass (Micropterus salmoides) in a 4.6-m (short) seine and an experimental 9.1-m (medium) seine was compared. The catch of intermediate bluegills (8-13 cm TL) in the medium seine was subsequently compared to their catch in a 15.2-m (long) seine. The medium seine was similar to the short seine for collecting bluegill fry. The medium seine generally required fewer hauls but more work to achieve the same level of precision when collecting YOY bass. The long seine was more effective at collecting intermediate bluegills than the medium seine. The experimental medium seine would provide no advantage over the short and long seines if used to conduct routine balance checks.

We investigated effects of selected physical factors on the catch rate of white crappie (Pomoxis annularis) in trap nets in Mississippi lakes. Population data were collected on 7,782 white crappie from 557 trap-net samples in the fall (N = 4,679 fish/243 nets) and spring (N = 3,103 fish/314 nets), 1987-1989. Generally, catch/day (N fish/24 hours) estimates were higher and less variable in trap nets set at water depths of 1.0-2.9 m and on bottom slopes of 0.0%-7.9%. Catch/day estimates were higher, but equally variable, in trap nets set perpendicular to the shoreline and at water temperatures of 16.0-19.9 C in the fall and 20.0-23.9 C in the spring. These findings indicate trap-netting efficacy could be augmented by sampling under the specified ranges of sampling conditions.

An intensive hoop net study was conducted on the St. Johns River, Florida, to: (1) estimate commercial hoop net effort, bycatch and initial gamefish mortality; (2) determine delayed mortality of game fish caught in hoop nets; and (3) estimate riverwide gamefish mortality in hoop nets. A survey of all known hoop net fishers revealed 38 fished 2,386 hoop nets for 794,300 net-days of effort in 1993. Between July 1992 and June 1993, 1,053 commercially-fished hoop nets were observed that were fished 7,320 net-days. Catfish (Ictaluridae) comprised 95% of the 87,278 individuals captured, while game fish comprised 2.3% of the total catch. Estimated riverwide hoop net-induced mortality in 1993 was 1 black crappie (Pomoxis nigromaculatus)l9.1 ha and 1 Lepomis spp./10.5 ha. We felt these low mortality estimates did not threaten gamefish populations on the St. Johns River, and recommended allowing the continued use of hoop nets.