Journal of the Southeastern Association of Fish and Wildlife Agencies

The commercial trotline fishery in the Laguna Madre, Texas, was simulated using fishery-independent sampling data to estimate landings of black drum (Pogonias cromis). Simulation of a commercial fishery can provide landings estimates and more precise estimates of confidence intervals. It can also provide information (i.e., by catch) not available through self-reported systems.

Using results from on-site creel interviews, the use and fishing success of 16 bait types for 8 game fishes were studied for bay and pass saltwater sport-boat anglers in Texas. The success of catching at least 1 fish was evaluated using percentage of successful fishing parties by fish species, bay system, and bait type. For all fish species, the use of different baits was not proportional to the success of these baits in catching fish; however, we could not determine whether this was caused by ineffectiveness of the investigated bait or anglers not directing this bait toward the investigated fish. A logistic regression model fitting the effects of bay system and bait type for each fish species adequately described the odds of success for fishing parties.

Fishery surveys utilizing electrofishing and gill nets have documented natural reproduction of striped bass in 2 Maryland impoundments: Liberty and Piney Run reservoirs. Natural reproduction has occurred for 5 years, 1986 through 1990, in Liberty Reservoir; and for 3 years in Piney Run Reservoir, 1988 through 1990. It was initially thought that reproduction occurred in Liberty Reservoir because the relatively hard bottom and high dissolved oxygen levels allowed hatching of striped bass eggs that descended to the bottom. Recent discovery of natural reproduction in Piney Run Reservoir, a small eutrophic impoundment, supports the theory that striped bass eggs may float or remain suspended in the water column until hatching occurs in these impoundments.

Striped bass (Morone saxatilis) were sampled during summer and winter in the St. Johns River, Florida, to determine effects of summertime thermal stress on fish condition. Regressions of log weight on log length for winter and summer fish had significantly different slopes (P < 0.001) indicating larger fish were less robust than smaller fish in summer as compared to winter. Data were arbitrarily separated into 3 size categories (small = <331 mm TL; medium = 331-500 mm TL; large = >500 mm TL) to investigate thermal related stress by size. No negative seasonal impacts could be detected for the small fish category. Although the seasonal slopes were not significantly different for either the medium or large fish categories, significant differences (P < 0.001) in line elevations indicated that summer fish weighed less for any given length than winter fish.

Twenty-four adult striped bass (66.8-84.6 cm; 4-7 years) from the McAlpine Pool of the Ohio River were fitted with internal radio transmitters and tracked from May 1989 through May 1990. Study fish were found to be very mobile, although seasonal movement patterns were predictable. Tagged striped bass utilized the tailwater and upper pool sections during the spring, summer, and fall. Little use was made of the lower McAlpine Pool sections by striped bass. Fish in the pool were most often located in water between 0 to 6 m (x = 92.1% all seasons). Twenty-four hour surveys determined that striped bass total daily movement ranged from 1.3 to 4.3 km (x = 2.1 km/fish), with movement per hour varying from 0 to .3 km/hour. Fifty-eight percent of the daily movement was during the day following by the crepuscular (23.7%) and night (18.3%) periods. Four striped bass (16.7%) were still active at the end of the study.

In recent years, a small scale bowfin (Amia calva) roe fishery in Louisiana has increased in both volume and value. To initiate an evaluation on the impacts of this fishery on bowfin populations, 3 study areas were selected to represent various ecosystems inhabited by bowfin. It was not possible to relate growth, size, and sexual maturity with age based on otolith samples. Length-frequency data suggested that 9-month-old fish ranged from 225-400 mm and 21-month-old bowfin may grow to 525 mm. Gonadosomatic indices showed a constant increase through February, and all females observed had spawned by early March. Gonadal development and length frequency data support the conclusion that most bowfin in Louisiana mature during their second winter. It appears that at least some bowfin mature before they become vulnerable to legal mesh (76 mm) gill nets.

This study was conducted to estimate the summer and winter hooking mortality of flathead catfish (pylodictis olivaris) caught on trotlines in the Colorado River and Kerrville Reservoir, Texas, and blue catfish (Ictalurus furcatus) caught on trotlines in Livingston Reservoir, Texas. Water temperatures averaged 12.2 and 13.3 C, respectively, during February and March flathead catfish winter experiments, and 27 C during summer experiments. Water temperatures averaged 12.5 and 24 C, respectively, during winter and summer blue catfish experiments. Flathead catfish (range = 352-675 mm total length (TL)) were caught with sizes 7/0 and 8/0 single hooks baited with live green sunfish (Lepomis cyanellus), bluegill (L. macrochirus), and goldfish (Carassius auratus). Blue catfish (range = 165-655 mmTL) were caught with sizes 4/0 to 6/0 single hooks baited with pieces of shad (Dorosoma spp.) and goldfish.

We assessed trotline hooking mortality of channel catfish (lctalurus punctatus) at Lake Palestine, Texas, from June through September 1989. Our objective was to estimate trotline hooking mortality of channel catfish using 3 hook types and identify factors relating to that mortality. Fish collected by trotline were confined for 72 hours in submerged cages. We examined relations between percent mortality and hook type, water temperature, and oxygen concentration using logistic analysis. A total of 214 channel catfish were collected by trotline; 40 (19%) were dead at the end of the 72 hour confinement period. Oxygen concentration was the only variable significantly related to mortality (P = 0.002). Our results indicate channel catfish have >80% chance of survival when caught on trotline and released, even under stressful conditions such as high water temperature, variable oxygen concentration, and confinement.

Historically, degradation of water quality from mining activity in the Monongahela River Basin adversely affected fish populations in the mainstem river. Improvement of water quality since 1971 has resulted in positive changes in fish populations. We assessed changes in the fishery by analyzing rotenone samples in relation to changes in water quality. Before 1970, pH ranged between 3.8 and 5.8 and alkalinity between 0.0 and 2.0 mg/1. After 1980, mean annual pH ranged from 7.0 to 7.3 and alkalinity ranged from 8.7 to 12.9 mg/1. From 1973 to 1990, mean fish biomass increased in nearly every sample from 41 to 355 kg/ha, Fish diversity also increased. The increase in biomass was significantly correlated with mean alkalinity, but not with mean annual river discharge or mean annual pH.

Passive integrated transponder (PIT) tags were placed in 15,344 triploid grass carp (Ctenopharyngodon idella) (200-280 mm total length) and length, weight, and tag-code data recorded for each fish at rates of 206 to 350 fish per hour. Only 43 fish (0.28%) died within 48 hours post-tagging. Survival of tagged (N = 122) and untagged (N = 131) groups of fish held in ponds 83 to 115 days post-tagging was >90% and near equal, except for 1 tagged and 1 untagged group where a columnaris disease outbreak occurred; survival in those groups was 68.0% and 69.1%, respectively. All tags were retained in the fish and functioned properly after 83-85 days in ponds. After 1 group of fish (N = 29) had been in a pond for 225 days, tag responses were found for all but 1 fish. The techniques used for tag placement and data recording utilized equipment generally available at most fisheries laboratories.

Trends in the abundance of young-of-year largemouth bass (Micropterus salmoides) and water level fluctuations from 1976 to 1988 in Grand Lake were evaluated to assess recruitment strength before (1976-1981) and after (1982-1988) a change in reservoir operations. Significantly positive relationships between abundance of young-of- year largemouth bass and days of littoral flooding during spawning and nursery seasons, drawdown during revegetation season in the previous calendar year, combinations thereof, and water levels during these seasons indicated recruitment of largemouth bass was influenced by water level fluctuations. Implementation of a new operating rule curve in 1982 seemed to affect recruitment only indirectly by minimizing drawdown during late summer, thereby decreasing the exposure of shoreline areas of the reservoir for revegetation during the latter part of the growing season.

Success and cost effectiveness of stocking larval vs. fingerling hybrid striped bass (o Marone chrysops X o M. saxatilis) were evaluated at Lake Sam Rayburn, Texas. Stocking success was evaluated using gill net catch rates of age-2 hybrids, mean length of hybrids at age 2, and relative annual mortality of stocked individuals. Hatchery production and stocking cost of larvae and fingerlings were compared. There was no significant difference between gill net catch rates of age-2 hybrids stocked as larvae vs. fingerlings. However, age-2 hybrids from larval stockings were significantly larger than those from fingerling stockings. Relative annual mortality of stocked larvae was significantly higher than for fingerlings. Stocking costs for larvae were less than half those for fingerlings.

The impact of changing the hybrid striped bass (white bass Morone chrysops o x striped bass M. saxatilis o; WBxSB) stocking strategy on 2 Texas reservoirs was evaluated. Stocking of WBxSB in lakes Arlington and Graham was increased from 20 fingerlings (25-76 mm TL)/ha and 112 fry (6 mm TL)/ha biennially, respectively, to approximately 50 fingerlings/ha annually. Annual fall or winter gill net surveys were conducted to monitor densities of WBxSB and gizzard (Dorosoma cepedianum) and threadfin (D. petenense) shad. Spring creel surveys were conducted to evaluate angler utilization of WBxSB. Scales from WBxSB collected in 1987 were aged to determine year class strength at each lake. Gill net catch rates of WBxSB increased significantly after fingerling stocking rate and frequency were increased. Catch rates of gizzard and threadfin shad did not change significantly.

Stream habitat and large woody debris (LWD) loadings were inventoried in 2 southern Appalachian wilderness streams by the basinwide visual estimation technique. Little Santeetlah Creek, in a wilderness watershed that has never been harvested, contained 4 times as much wood and nearly twice as many habitat units (e.g., pools and riffles) as did Lost Cove Creek in a forested watershed, typical of the southern Appalachians, that was clearcut 80 years ago. Where stream widths were similar, pools and riffles in Little Santeetlah were smaller and more numerous than in Lost Cove Creek. Naturally occurring LWD influenced the structure and configuration of habitat in southern Appalachian Mountain streams.

Food habits of rainbow trout were studied at 3 locations for 1 year on the Center Hill Dam tailwater in central Tennessee. Staple food items consisted of isopods (Lirceus sp.) and chironomids. Seasonal food items from Center Hill Reservoir (threadfin shad and Daphnia sp.) were highly utilized and contributed nearly 60% to the total volume of food items taken. Occurrence of algae in rainbow trout stomachs was common and appeared to be related to seasonal forage base. Condition of rainbow trout did not significantly change with season, but was usually significantly higher closer to the dam.

Nineteen adult walleyes were implanted with ultrasonic transmitters and tracked for 2 years at Meredith Reservoir, Texas, to determine specific behavioral characteristics. During the spawning period tagged walleyes established an activity pattern consisting of 3 phases: pre-staging, movement to within 5.5 km of the dam; staging, movement to within 2.2 km of the dam; and spawning on the rip-rap of the dam. Individual walleye established home range areas ranging in size from 141 to 2,517 ha. Fish were located most frequently in water ≤8 m deep within 100 m of shore. Most locations were along brushy or rocky shorelines.

I used a normal-skew model to calculate length-specific selection curves for white bass caught in gill nets in 55 Texas reservoirs. I used these selection curves to adjust 2 size-structure indices, proportional stock density (PSD), and relative stock density (RSD) for gill net mesh-size selectivity. Differences between adjusted and unadjusted values of PSD and RSD were small (0.6 and 2.0, respectively) when the unadjusted values were extreme (i.e., ≤10 or ≥91). When unadjusted values of PSD and RSD were between 10 and 91, mean absolute differences between adjusted and unadjusted values were 5.6 and 6.7, respectively. There were no obvious patterns to the differences between adjusted and unadjusted values of PSD and RSD.

During a 2-year period, 250,000 Florida largemouth bass fingerlings were stocked among the endemic northern largemouth bass population of Tradinghouse Creek Reservoir (1985 = 185/ha, 1986 = 123/ha). We used electrophoresis to estimate proportions of Florida, northern, and Florida x northern intergrade largemouth bass within pre-stocking, stocking-year, and post-stocking year cohorts. Ages of largemouth bass were determined by examination of whole otoliths. The proportion of Florida phenotypes within the stocking-year cohort was not increased when the stocking rate was more than 50/ha greater. Stocked Florida phenotypes comprised 6% and 25% of the 1985 and 1986 cohorts, respectively, at age 1. Implementing a less restrictive harvest regulation accelerated introgression of the Florida genome by providing sizerelated, selective harvest of larger, northern largemouth bass.

The author encourages wildlife law enforcement officers to develop and maintain a cooperative rapport with convicted offenders in an effort to increase the number of informants and cooperators as an aid to cause compliance with regulations.

As a result of Fair Labor and Standards Act requirements, Texas Parks and Wildlife Department (TPWD) supervisors became concerned about time lost from game wardens responding to reports of violations from sportsmen in which no violation existed. From this concern a cooperative program was initiated with the Gulf Coast Conservation Association (GCCA) in which a select group of their membership was trained in how to recognize and report violations to game wardens. This program has drastically reduced time lost from game wardens responding to erroneous reports of violations and has significantly increased the ratio of apprehensions and seizures of illegal equipment.

The Japanese cultured pearl industry has caused the demand for the freshwater mussel shell to increase throughout the Southeast. With the market value of the resource increasing, enforcement officers must use varied enforcement techniques to apprehend law violators.

A basic guide is provided for safety, setup, and use of deer decoys to assist the wildlife officer in apprehending night deer hunters.

The enforcement of wildlife laws becomes more complex and complicated each day and requires the wildlife officer to use every available tool to perform his job. Wildlife forensic techniques provide scientific methods to supplement the wildlife officer's work in the field. Wildlife forensic techniques provide methods necessary to answer law enforcement problems which remained unanswered in the past but have been answered today, and to solve tomorrow's problems with answers which do not exist today. Wildlife forensics is not a panacea for the wildlife officer, however, it is another tool in his arsenal against the poacher. The science of wildlife forensics is similar to air travel. Yesterday's wildlife officer flew a propeller driven plane. Today's wildlife officer has moved into the jet age. Tomorrow's wildlife officer will enter the space age.

Bloodhounds used as mantrailers canbe an invaluable instrument in wildlife law enforcement. The human body consists of approximately 60 trillion cells which are constantly dying and being sloughed off at the rate of about 50 million cells per second. These dead cells are acted on by bacteria which causes them to give off a gaseous odor. Each odor is slightly different, creating a unique, individual, human odor which may determine the fate of a wildlife law violator.

The author describes the development of this State's program to investigate crimes dealing with hazardous waste disposal. Particular emphasis is placed on the pitfalls and advantages of a hybrid positionas used in this state. As illustrated in the summary, it is not beyond the scope of state wildlife enforcement agencies to investigate and prosecute these crimes that do vast amounts of damage to the natural resources. In many cases, an act of hazardous waste disposal can do more damage to an ecosystem and its natural resources than an entire family or even generations of poachers.