Journal of the Southeastern Association of Fish and Wildlife Agencies

In temperate reservoirs, habitat quality and availability can be vital to year-class formation of young largemouth bass. We assessed littoral habitat availability for largemouth bass in a tropical reservoir. Habitat characteristics (slope, substratum, and cover) were measured at 5 water levels (169, 170, 171, 172, and 173 m above mean sea level) at 15 30-m sites in Lucchetti Reservoir. Total structural habitat availability declined sharply at lower water levels, and both inundated terrestrial vegetation and woody debris were absent at the lowest water level examined. Coarse substrates (gravel, cobble, and boulder) were more common at higher water levels, and fine substrates (primarily clay) dominated at lower water levels. Annual catch rates of age-1 largemouth bass from 1993-2000 were significantly related to estimated mean structural habitat availability for the previous spawning season.

We described seasonal movements of smallmouth bass (Micropterus dolomieu) in Lake Moomaw, a 1,024-ha western Virginia impoundment, using ultrasonic telemetry in combination with a mark-recapture tagging study. Documentation of lake sections occupied over the course of a 2-year period was used to assess the extent and magnitude of spring migrations of bass to the headwaters of the reservoir. Fish using the headwaters during the spring were drawn mainly from adjacent areas within 9 km of the headwaters, although fish from as far away as the dam were recovered in the headwater area. Use of the headwaters by smallmouth bass from the lake was estimated at less than 20% of the adult population during the spawning season. Redistribution information was also collected and showed that smallmouth bass returned to areas previously occupied prior to spawning.

Diet and growth of the 1993 year-class of age-0 largemouth bass were determined in Ledbetter Embayment of Kentucky Lake. Diet was analyzed to determine the relationship between diet quality and the resulting size structure of the cohort. Length-weight and head capsule-weight regressions were used to estimate the dry weight of prey items in the diet. Largemouth bass were divided into 2 size classes (large and small) based on the mean length for each sampling date. Growth rates were calculated for both classes and compared with piecewise linear regression of total length on day of the year with the use of an additional dummy variable. There was a pivotal period in mid-July when there was a divergence in growth rates. The growth rate of small age-0 fish slowed dramatically, while the growth of large age-0 largemouth bass increased.

Briery Creek Lake is a 342-ha impoundment in central Virginia that has become widely recognized as having Virginia's premier trophy largemouth bass (Micropterus salmoides) fishery. We estimated largemouth bass density (fish/ha) using a multiple census mark-recapture technique along a 3.2-km section of shoreline and by using the Leslie catch-depletion technique in a 4.1-ha cove. An access point creel survey was conducted in 1999 and 2000 to estimate angler catch and harvest. We used a dynamic pool model to simulate the effects of a newly imposed 356-610 mm protected slot limit with respect to size structure, harvest, yield, and abundance of trophy (?560 mm) largemouth bass. The mark-recapture study estimated largemouth bass density to be 44 fish/ha and the number of trophy largemouth bass in the lake to be 318. The Leslie catch-depletion technique estimated the density of largemouth bass to be 43 fish/ha and the number of trophy fish to be 397.

Striped bass fingerlings (Morone saxatilis) acclimated to hard water (110 mg/liter as calcium carbonate, 41.0 mg/liter as calcium) were exposed for 96 hours at pH 7.7, 6.1, or 4.2 in hard water. In another experiment, striped bass fingerlings acclimated to soft water (32 mg/liter as calcium carbonate, 9.5 mg/liter as calcium) were exposed for 96 h at pH 7.7, 6.1, or 4.2 in soft water. No mortalities occurred during the experiments. The primary stress response and electrolyte disturbance were less severe in fish acclimated to hard water than in fish acclimated to soft water, suggesting that calcium acclimation history may be an important consideration when stocking striped bass into acidic waters.

The aquifer that supplies water to most channel catfish (Ictalurus punctatus) hatcheries in the Yazoo Basin of the Mississippi River flood plain in west-central Mississippi has a hardness of <10 mg/liter as CaCO3. Calcium hardness <10 mg/liter is known to reduce survival and growth of catfish sac and swim-up fry, but effects of low hardness on fingerling growth and survival have not been determined. We examined the effects of hardness (5 mg/liter and 67 mg/liter as CaCO3) on survival and growth of fingerling (2.0-3.2 g initial weight) channel catfish (USDA-103 line), blue catfish (I. furcatus, D&B line), and channel X blue catfish hybrids (USDA-103 channel X Rio Grande blue catfish) in 80-liter aquaria. Survival was ?99% in all treatments over the 33-day experimental period. Low calcium resulted in significantly (P < 0.05) reduced net weight gain in both channel (4.4±0.07 g vs.

A population of catfish presumptively identified as channel catfish (Ictalurus punctatus) found in Lake Maurepas in southeast Louisiana matures at a small size and early age (<170 mm TL and <2 years) compared to other populations in southern Louisiana (>500 mm TL and 3 to 4 years). In addition, these catfish have a protracted spawning period. The peak spawning time coincides with cultured channel catfish, but a percentage of the population spawns throughout the summer months. These fish are harvested at a small size and support an important but contentious commercial fishery. The small size and early age at sexual maturity have raised several questions: are these channel catfish, a distinct subspecies, or a hybrid between channel catfish and another ictalurid? These reproductive characteristics would prove useful for research, especially if the taxonomic uncertainty could be resolved.

Algae infestations are a common problem in catfish culture ponds. To treat filamentous algae, frequent applications of copper sulfate are necessary. Free copper is toxic to fish, and its concentration is dependent on a variety of factors such as its reaction with carbonate ions, absorption by phytoplankton, and temperature. The Frankfort Fish Hatchery has been using a colorimeter to measure the concentration of free copper ion after the application of copper sulfate to ponds stocked with blue catfish and channel catfish fingerlings. The use of the colorimeter allows managers to determine when the free copper concentration has decreased enough to safely treat the pond again. It has been observed at this hatchery that blue catfish are more sensitive to copper sulfate treatment than channel catfish. During the 2000 production season, the average survival of 3 blue catfish ponds treated with copper sulfate pentahydrate was 75%.

The paddlefish (Polyodon spathula) population in the Ohio River Basin is an inter-jurisdictional resource shared by 8 states and managed with 3 different strategies, restoration, protection, and harvest. These contrasting management strategies evolved from a historical gradient in abundance of paddlefish from the upper to lower reaches, differential impact of anthropogenic factors, and U.S. Supreme Court settlements, which changed river ownership among lower Ohio River states. Ohio River Basin states participated in a national paddlefish study during 1995-1999 verifying movement of paddlefish across state boundaries in the Ohio River. Recognition that paddlefish likely represent a single population within the Ohio River and consideration of the value and vulnerability of paddlefish as a source of caviar has created a need for comprehensive and cooperative management of paddlefish among Ohio River states.

Movement, distribution, and habitat use of walleyes (Stizostedion vitreum) in Laurel River Lake, Kentucky were determined by radio-tracking 35 walleyes for 605 days (mean = 249 days) from March 1994 through November 1995. The goal of this study was to increase the angler utilization of walleyes in Laurel River Lake by educating anglers on walleye movement patterns, habitat usage, and distribution within the lake. Walleye movement (as measured in distance between weekly locations) was highest during the spring (median = 120 m/day) and lowest during the summer (median = 53 m/day). During the summer, most walleyes confined their activities to specific areas of the lake and were often located in the same area during consecutive weeks. Activity areas ranged from 2 to 590 ha with 75% of walleyes utilizing areas <300 ha. Walleyes were widely distributed throughout the lake during each season, although only 2 walleyes remained in the upper Laurel River arm during July and August.

Although fertilization has been a common practice to increase fish production in low nutrient lakes and ponds, applicability of the practice in larger reservoirs is questionable. Under the assumption that increased algal production moves up the food web to fish, we fertilized Grayson Lake, Kentucky, surface water with high N to P ratio fertilizer during springs 1994 and 1995. April through July 1994 we added 1 kg P/ha and 22 kg N/ha over a 9-week period to approximately 162 ha of lake surface area. During 1995 we increased loading to 7 kg P/ha with 22 kg N/ha. Weekly photic zone water samples were taken directly after fertilization (within 1 day). Water quality and primary production were assessed in fertilized and unfertilized lake regions. Alkalinity, inorganic nitrogen, soluble reactive phosphorus, and chlorophyll a concentrations were not significantly higher in the fertilized areas (N = 40 in 1994, N = 50 in 1995, P > 0.1 Mann-Whitney test).

The Gulf sturgeon (Acipenser oxyrinchus desotoi) is a threatened anadromous species in the Gulf of Mexico. Nineteen subadult Gulf sturgeon were equipped with ultrasonic transmitters (34-40 kHz) in the Choctawhatchee River and Bay during fall 1996 and 1997 before their entry into marine habitat. The movement and habitat use of Gulf sturgeon in the estuarine/marine environment was determined from November through April 1996-1999. A total of 344 sonic contacts were made in this study. We documented fish location using a GPS and recorded water depth, temperature, salinity, substrate type, and distance from shore. Subadult Gulf sturgeon migration from the freshwater riverine system to the marine system was influenced by an increase in river flow and a decrease in water temperature. Fish moved throughout Choctawhatchee Bay, but mostly used shoreline areas. The use of 5 geographic areas by 95% of telemetered Gulf sturgeon may be linked to food availability.

Little published information exists on shortnose sturgeon (Acipenser brevirostrum) in the Chesapeake Bay. During a reward program for Atlantic sturgeon (Acipenser oxyrinchus), 32 shortnose sturgeon were captured in the Chesapeake Bay and reported by commercial watermen between January 1996 and January 2000. Thirteen of the 32 shortnose sturgeon were sonically tagged, and 6 of these telemetered individuals were tracked during daylight hours within the upper Chesapeake Bay. The distance (km) and time (days) between consecutive relocations were use to estimate movement rates as km/day. Localized and wandering movements of telemetered shortnose sturgeon were observed within the upper Chesapeake Bay based on extended time intervals between relocations, but individuals were rarely relocated on consecutive days. Telemetered shortnose sturgeon were generally relocated in areas that exceeded the average available water depth.

The objective of this case history was to document the response of the crappie (Pomoxis spp.) population at Kentucky Lake to restrictive harvest regulations. In the late 1980s and early 1990s, crappie abundance declined due to poor recruitment and high mortality during severe drought years. A tagging study estimated minimum exploitation at 45%. Following the drought, restrictive harvest regulations (30 fish creel and 254 mm minimum length limit) were implemented to reduce exploitation, and subsequently increase survival of crappie from age 1 to age 2. Annual survival of these smaller crappie, determined from cohort analysis, was increased from approximately 21% to 48% following implementation of restrictive regulations. Abundance of adult crappie increased following the restrictive regulations. Recruitment variability was not affected by the restrictive regulations, and probably was affected more by environmental changes.

The North Carolina Wildlife Resources Commission (WRC) stocks striped bass (Morone saxatilis) fingerlings in Lake Norman to support a put-grow-and-take fishery. Members from 2 angling groups demanded the WRC raise striped bass stocking rates and increase available striped bass forage. The agency contended increasing stocking rates would exacerbate poor condition and slow growth among the lake's striped bass. Conflict between the WRC and anglers arose when the agency indicated it would not raise striped bass stocking rates, stock additional clupeids, or introduce alosids. An Advisory Committee was established consisting of non-WRC fisheries scientists, members of the 2 angling groups, several members of the fishing media, and local fishing guides. The dynamics of the Committee helped to mediate the conflict and permitted anglers and WRC managing biologists to develop more trusting and pragmatic relationships.

Lake Tanglewood, Texas, is a eutrophic reservoir with an excessively abundant gizzard shad Dorosoma cepedianum population comprised of primarily large individuals (>180 mm total length [TL]). Fingerling (40 mm TL) hybrid striped bass (Morone saxatilis x M. chrysops) were stocked at high rates in 1992 (490/ha) and 1993 (245/ha) to restructure the gizzard shad population. Small gizzard shad (<180 mm TL) declined in abundance 1 year after hybrid striped bass were introduced, presumably as a result of hybrid striped bass predation. With reduced recruitment, large gizzard shad abundance steadily declined. Gizzard shad year class production increased after the abundance of large gizzard shad declined, suggesting that a high density of large gizzard shad may suppress gizzard shad year class production.

We compared relative abundance, size distribution, growth, and harvest of bluegill (Lepomis macrochirus) before and after implementation of a 178-mm minimum length limit at 144-ha Purtis Creek State Park Lake (PCSPL), Texas. Relative abundance [catch/hour of electrofishing (CPUE)] was significantly lower in post-regulation years (1993-1995, 243/hour) than in pre-regulation years (1990-1992, 520/hour). However, this decline was likely more attributed to recruitment patterns than to regulation effects. There was no significant difference (P = 0.18) between pre- and post-regulation bluegill size distribution. The only significant change in pre- and post-regulation mean length-at-age was for age-1 bluegill (134 mm vs. 123 mm, P = 0.04). However, this difference is suspect due to low sample sizes and the effect of extended spawning period on the “actual” age of bluegill captured in the fall.

We conducted 2 experiments to evaluate the potential of feeding schedules designed to elicit compensatory growth and increase growth of hybrid bluegill (F1: male bluegill Lepomis macrochirus x female L. cyanellus). The first experiment evaluated a commercially prepared pellet and consisted of 3 treatments: fish fed every day and fish starved for 2 or 4 days after cessation of hyperphagia. The second experiment evaluated 2 diets, mealworms and commercial pellets, fed every day and on a 2-day starvation schedule. Growth and feed consumption in starvation treatments did not significantly exceed that of controls in either experiment. Our results contradict those of earlier studies that showed increased growth and consumption with similar feeding methods.

Historical records and natural history collections have been used as important tools to determine the status of populations. The objectives of this project were to compile a list of the fishes that have inhabited Triplett Creek and to identify changes in the fish assemblage in Triplett Creek. Historical records and vouchered specimens document 80 species from 19 families in the Triplett Creek system between 1890 and 1998. In a survey of the Triplett Creek system in 1999 and 2000, 16,554 specimens were collected, representing 54 species from 11 families. At least 3 fish species are considered extirpated from Triplett Creek, and 3 new fish species [Gambusia affinis (western mosquitofish), Moxostoma macrolepidotum (shorthead redhorse), Percina copelandi (channel darter)] were collected. A comparison of 3 collecting periods using Jaccard's Coefficient of Community Similarity (CC) indicates that the fish assemblages are similar (pre-1950 vs. 1950-1998 CC=0.77; pre-1950 vs.

Allegheny woodrat (neotoma magister) populations in the northern and western limits of the range have been greatly reduced in recent years, increasing the need to locate and monitor both threatened and seemingly stable populations. We tested the feasibility of predicting areas of suitable habitat for the woodrat in the Daniel Boone National Forest (DBNF) by using a Geographic Information System model. Several themes depicting woodrat habitat variables were overlaid to produce a comprehensive map displaying likelihood of woodrat occurrence. Logistic regression analysis was used to determine effect of each habitat variable on woodrat occurrence based on a sample of 394 known woodrat occurrence sites, 511 random sites, and habitat data including slope, landuse, site geology, forest cover, and locations of forest openings, clifflines, streams, and roads. The resulting habitat model correctly classified 97% of the 416 independent woodrat locations at the 0.50 probability level.

Successful regeneration of oaks on better sites (SI50>60) has proven difficult in recent decades due to competition from faster growing species and well-established advanced regeneration from more shade-tolerant species. The suppression of fire is thought to have played a critical role in allowing this largely fire-intolerant competition to dominate many upland hardwood forests at the expense of oaks. As part of a larger study examining the role of prescribed fire in regenerating upland oaks, seasonal prescribed burns were applied to first-stage shelterwood harvested stands on Horsepen WMA in the Virginia Piedmont in 1995. We surveyed small mammal communities in these stands to assess the impact of such fires on this component of the fauna.

There is little published information available on non-target captures during small mammal trapping. We used a variety of snap traps baited with a rolled oat-peanut butter mix to capture 2,054 individuals from 9 genera of small mammals in a study of small mammal and avian community structure in riparian areas and adjacent loblolly pine (Pinus taeda) plantations. We also captured 170 individuals from 24 non-target species over 122,446 trap-nights. Trapping was conducted from 1990 throught 1995 in 57 riparian areas and adjacent pine plantations in the Ouachita Mountains, Arkansas, during 10-day periods each February. Overall, 7.6% of individuals captured were non-target species. Approximately 78% of non-target captures were birds, 19% were mammals, 2% were amphibians, and 1% were reptiles. Rat traps accounted for 53% of total non-target captures; museum special traps, 29%; and mouse traps, 18%.

Three species of bats are endangered in Kentucky: the Indiana bat (Myotis sodalis), the gray bat (M. grisescens), and the Virginia big-eared bat (Corynorhinus townsendii virginianus). Because some level of monitoring of these bats has taken place at Kentucky caves for several decades, trends can be assessed and some effects of management practices can be evaluated. In Kentucky, populations of Indiana bats continue to decline despite numerous protection efforts, populations of gray bats appear stable, and populations of Virginia big-eared bats are increasing.

We studied short-term response of gray squirrel (Sciurus carolinensis) populations to nest boxes in mixed-pine (Pinus spp) hardwood and even-aged pine forests in Alabama from December 1988 to September 1990. Nest boxes (5/ha) were installed in 3 mixed pine-hardwood and 3 even-aged pine stands. We used a split-plot design to determine if populations differed between treatment (with nest boxes) and control (without nest boxes) halves of mixed pine-hardwood areas. In even-aged pine area, post-treatment population indices of squirrels (minimum number known to be alive [MNA]) were compared to pre-treatment indices collected by Fisher and Holler (1991). We captured 260 squirrels 1,102 times in 33,480 trap-days. Number of individual squirrels captured after nest box installation was double in treatment (125) versus control halves (63) of mixed pine-hardwood areas. Population estimates did not differ between treatment and control.

We assessed taxonomic status of wild canids in Kentucky using 13 cranial measurements on 143 known canid skulls in a multivariate statistical procedure to classify 56 unknown canid skulls from Kentucky. Discriminant function analyses revealed complete separation of canid taxa between coyotes and dogs, although coyote-dog hybrids had significant overlap with coyotes. Hybridization between coyotes and dogs in Kentucky occurred in less than 10% of unidentified canids. Our findings suggest that wild canids in Kentucky are best classified as coyotes, Canis latrans.