Journal of the Southeastern Association of Fish and Wildlife Agencies

The increasing importance of the walleye (Sander vitreus) fishery in the New River, Virginia, and recent research findings motivated characterization of its genetic composition. Movements of radio-tagged fish suggested that walleyes living in Claytor Lake and the upper New River tend to spawn in different areas. In this study, allozyme, microsatellite DNA, and mitochondrial DNA genetic marker data were analyzed to assess population genetic differentiation among collections of New River walleye. The walleyes within Claytor Lake are a panmictic population, presumably resulting from years of stocking different genetic backgrounds and subsequent interbreeding. However, the genetic structure of walleyes from the New River shows the presence of more than one population. Fish in the New River system carry three previously unknown mitochondrial DNA haplotypes (43, 44, and 45), as well as high frequencies of characteristic alleles at particular microsatellite DNA loci.

Studies using otolith chemistry to distinguish fish stocks in fresh waters have suggested that spatial heterogeneity in basin geology determines the scale of stock discrimination possible with this approach. However, no studies have illustrated an association between spatial variation in fish otolith chemistry and watershed geology. We consider this relationship in the context of a recent study describing within- and between-river variation in trace element chemistry of otoliths from YOY smallmouth bass (Micropterus dolomieu) from the Maury and James rivers (Virginia). Cluster analysis of multivariate geologic data for discrete river segment basins illustrates a phenomenological association between geologic heterogeneity and our ability to discriminate spatial groupings of fish from their otolith chemistry.

Mycobacteriosis is a widespread, chronic disease of estuarine fishes. Recent studies by scientists at the National Fish Health Research Laboratory, Leetown, West Virginia and the Virginia Institute of Marine Science, Gloucester, have shown infection rates in striped bass (Morone saxatilis) of up to nearly 62% in certain Virginia tributaries to Chesapeake Bay (Bay). Of the several mycobacterial species known to infect striped bass from the Bay, several are known to be zoonotic including M. marinum and M. fortuitum. In this paper we discuss the incidence and prevalence of mycobacterial infections in striped bass and contrast these with human epidemiological data on the occurrence of cutaneous mycobacteriosis in the Bay's human population collected by the Virginia Department of Health and the Maryland Department of Health.

In 2002, the Missouri Department of Conservation (MDC) conducted a statewide survey of licensed anglers in Missouri who fished for catfish during 2001 to gain information on angler demographics, species preferences, angling behavior, and angler opinions on catfish management. Catfish anglers were grouped by the species of catfish (flathead catfish Pylodictis olivaris, channel catfish Ictalurus punctatus, blue catfish I. furcatus, or bullhead catfish Ameiurus spp.) they preferred to fish for, and differences among preference groups related to demographics, angling behavior, and opinions on catfish management were examined. Results indicated that while catfish anglers in Missouri are a diverse group, and their preferences, opinions, and behaviors differed depending on species preference of the anglers, Missouri catfish angler groups were more similar compared to catfish angler groups in other states.

Blue catfish Ictalurus furcatus electrofishing samples were collected on nine Oklahoma reservoirs and age and growth estimates were made on seven of these reservoirs. Catch rates of blue catfish were high (up to 700/h) on all reservoirs sampled but catch rates of preferred-sized (>762 mm total length) catfish were low (<5/h). Growth rates varied widely both within and among reservoirs but were generally slow with blue catfish not reaching preferred size until ages 13-16. A negative relation between catch rates and growth was identified. Total annual mortality rates averaged 26% for the seven populations sampled. Given growth and mortality rates estimated in this study, only 2%-3% of age-1 blue catfish reach preferred size in Oklahoma reservoirs. A management initiative stressing angler harvest of small individuals while restricting harvest of preferred-sized blue catfish is suggested.

We used biotelemetry to monitor monthly adult white crappie locations and core-use-area sizes at Lyndon B. Johnson (LBJ) and Waco reservoirs in Texas over two 6-month periods (December 2000-May 2001 and November 2001-April 2002) and tested whether deploying trap nets at sites near known fish locations and at similar sites predicted to contain fish would result in increased trap-net catch per effort compared to randomly selected sites. No evidence suggested crappie preferred different depths depending upon the time of year in LBJ or Waco reservoirs. We observed fish further from shore in January compared to April in LBJ Reservoir, but all months were similar for Waco Reservoir. The majority of fish locations (>55% for both reservoirs throughout study) were further from shore than our trap nets effectively fish (21.3 m).

Spawning behavior and hybridization of Etheostoma nigrum and E. olmstedi were studied in the lab using wild individuals collected from populations in central Virginia. Hybridization is common in the genus Etheostoma, but there have been conflicting results in studies involving E. nigrum and E. olmstedi. The question is pertinent to central Virginia because populations with characteristics intermediate of the two species occur there, and it may be that these are hybrids. We collected both darter species in the wild and placed various inter- and intra-specific mating pairs in small aquaria. Males spent more time than females in nuptial behavior (24.1% v. 7.5%), the percentages were not different between species, but E. nigrum males spent more time courting E. olmstedi females than they did their own species (32% v. 12.4%). Viable eggs were produced in 6 of 24 tanks, including two inter-specific crosses. In both inter-specific crosses the female was E. olmstedi and the male was E.

Kentucky Reservoir on the Tennessee River supports a diverse freshwater mussel community including federally-listed endangered species. Resource extraction operations have been conducted on the Tennessee River since at least the 1920s. The condition of abandoned dredge sites as aquatic habitat for benthic organisms, including freshwater mussels, is relatively unknown. Objectives of this study were to determine the condition of abandoned dredge sites as aquatic habitat for freshwater mussels, compare species richness and density between sites in relation to years post dredging, collect information relevant to future permitting consultations, and provide a greater understanding of the effects of resource extraction in a large regulated river. Six hundred 0.25 m-2 quadrat samples were collected and processed from 12 study sites.

We evaluated the ability of oxytetracycline hydrochloride (OTC) and calcein (CAL) to double-mark otoliths in largemouth bass (Micropterus salmoides, LMB) fry and fingerlings. To observe longevity of marks, fish were sampled at six-month intervals for two years. Marks on fry otoliths disappeared rapidly regardless of chemical used; most marks were not visible after 180 days. Marks from CAL on fingerling otoliths were short-lived; 50% were not visible after 180 days. Marks from OTC on fingerling otoliths were visible on 100% of treated fish and were retained throughout the two years of study. Immersion-marking with OTC of fingerlings is a simple, effective, and relatively long-lasting technique for mass-marking LMB for various fisheries assessments. We successfully double-marked fingerling LMB with OTC when we imposed a two-week interval between marks. Alternate marks with OTC and CAL were unsuccessful because readers were often unable to distinguish between the OTC and CAL marks.

Smallmouth bass (Micropterus dolomieu) have been the preferred species of New River anglers since the early 1960s. Since the early 1960s, shifts in New River smallmouth bass population conditions have occurred. Some of these shifts are due to changed size limits which altered angler behavior. However, a number of unexplained changes prevent definitive analysis of causative factors. The New River smallmouth bass fishery of 1982 and 1983 was characterized by high numbers of sublegal fish (< 305 mm), slow growth, poor survival, and low relative weights. These characteristics shifted to conditions indicative of a more healthy population subsequent to the implementation of a 279- to 356-mm protected slot limit in 1987. The New River smallmouth bass fishery is currently managed with a 356- to 508-mm protected slot limit, reflecting current management emphases on producing trophy bass, while continuing harvest of numerous bass < 356 mm.

We assessed the economic contribution of black bass tournament angling to the total economic value of the black bass (Micropterus spp.) fishery from 1 March 2001 to 28 February 2002 at O. H. Ivie Reservoir, Texas, a popular black bass tournament reservoir in rural west Texas. Creel surveys and mail-out questionnaires were used to estimate number of black bass tournaments, black bass tournament and non-tournament angling effort, and direct angling expenditures. An estimated 147 black bass tournaments were held on the reservoir during the study period. Despite the high number of tournaments, we found that tournament angling effort for black bass (27,348 h, RSE = 31) was greatly exceeded by non-tournament angling effort (110,268 h, RSE = 19) and comprised only 20% of total black bass angling effort and 15% of all angling effort expended at the reservoir.

Larval threadfin shad (Dorosoma petenense) collected in August trawl samples from Hugo Reservoir raised questions about the spawning potential of the parental fish population. Adult threadfin shad were collected weekly from 24 March to 25 August 1999 to determine their reproductive state. Gonadal somatic index (GSI) values for medium and large size classes increased until mid-May, and then steadily decreased. However, in spite of decreasing GSI values, mature ova (greater than 0.53 mm in diameter) were present in ovaries through mid July. It is likely that threadfin shad were capable of prolonged spawning throughout the spring and summer. A small proportion (4%) of age-0 threadfin shad matured within two to three months of hatching and served as a brood source for the summer larval production.

No paper was submitted with this abstract. Abstract was too long so please refer to pdf.

No paper was submitted with this abstract. Abstract was too long so please refer to pdf.

Oaks (Quercus spp.) are one of the most widely distributed tree genera in North America and prevalent in most of the major forest type groups in the eastern United States. In spite of this prevalence, concern exists that oak forests are aging with an insufficient base of young stands to replace them. Using data from the USFS Forest Inventory and Analysis (FIA) program collected in 1989 and 2000, I estimated the current distribution and abundance of select oak forest types and oak species within the red and white oak subgenera in 29 eastern states. I also examined trends in the distribution and abundance of the species and oak forest types over the past decade. In 1989, oak stems represented 32% of the intermediate forest canopy and 52% of dominant and co-dominant classes. These numbers declined to 21% and 47%, respectively, by 2000.

No paper was submitted with this abstract. Abstract was too long so please refer to pdf.

The oak forest type in the Central Hardwoods Region (CHR) is the largest forest type in the United States. Mature forests (>80 yr) in the CHR are dominated by oaks (Quercus spp.) regardless of site, aspect or slope. However, without proper management, oaks on intermediate and mesic sites will be replaced by more mesophytic species, such as maples (Acer spp.) and tuliptree (Liriodendron tulipifera). In general, oaks will dominate xeric sites such as ridgetops because of their resistance to drought. The key to managing a sustainable oak forest is obtaining ample advanced oak regeneration: stems greater than 1.2 m (4 feet) in height. This is accomplished by managing light intensity. Currently, forests in the HR are 1.5-2 times as dense as the forests at the time of European settlement. In the past, fire was the ecosystem process that maintained the open woodland settings which provided the proper light conditions for oak forest sustainability.

Declines in the abundance of oak (Quercus spp.) and the failure of oak to regenerate after harvest are widespread problems in eastern North America. Sustaining oak forests will require large-scale and long-term effort. Most of the oak forest resource is owned by individuals, collectively referred to as non-industrial private forest (NIPF) owners. Conservation on NIPF lands is inherently difficult because ownership objectives vary, land tenure is generally short, and land parcels are small. Few NIPF owners have technical training in forestry or wildlife management. Timber harvest is generally conducted without the help of natural resource professionals and silvicultural techniques that would maintain oak are rarely used. Technical advice and support is available for NIPF owners through both public agencies and private organizations. Public support is delivered through a network that involves the university extension service, the state forestry agency, and the U.S.

Hardwood forests in eastern North America have been important to the nation's economy from wildlife, timber, and recreational perspectives. Since colonial times, the existence, structure, and function of these forests have been subjected to many challenges. In the westward expansion of this country, forested land was often converted to agriculture. More recently, marginal bottomland sites were drained or harvested to create new opportunities for row cropping. Exotic forest pests, such as chestnut blight (Cryphonectria parasitica) and gypsy moth (Lymantria dispar), have further impacted hardwood forests. Many hardwood forests contained significant populations of oak (Quercus spp.) species, which have diminished over time. Correspondingly, wildlife populations that depend on hard mast have been negatively impacted. Restoration of an oak component or enrichment of existing oak populations is a common goal for many wildlife organizations and agencies.

Fossil pollen records depict the forests of the Ozark Highland as being dominated by oaks (Quercus spp.) for the last 4,000 years. Early explorers and naturalists from Desoto to Schoolcraft left written records of forest conditions and the impact of anthropogenic influences such as fire and the use of forest products on the upland landscapes. Fire scar studies from Missouri and Arkansas confirm these influences and report average historical fire intervals of <15 years from the mid 1600s through the early 1800s. The turn of the 20th century spawned drastic changes in disturbance regimes including fire suppression. Oak dominated forests in the Ozarks and Boston Mountains by the 1970s had become three times as dense as a century before. Then in 1997, with insect populations at record levels and the occurrence of a minor drought, an oak decline event had devastating effects on an estimated 261,000 ha of the Ozark National Forest.

Multi-agency cooperative approaches have proven to be an effective, pragmatic, and often necessary means of achieving landscape-level wildlife conservation goals. The most compelling and historic examples involve bird conservation initiatives. Wildlife conservation agencies have collaborated in addressing broad scale population and habitat challenges. These collaborations began with the Migratory Bird Treaty Act and the advent of the Flyway management system. Efforts have increased with the North American Waterfowl Management Plan and the development of Joint Ventures and more recently with Partners in Flight and associated bird conservation initiatives. The challenges associated with sustaining eastern oak ecosystems are somewhat different than bird conservation issues because there is no focal species group, the problem is insidious, and existing management of private lands represent a major source of the problem.

Random active surveillance for Chronic Wasting Disease (CWD) in free-ranging populations of cervids is challenging due to low prevalence and heterogeneous distribution of the disease. Furthermore, geographic areas are at different levels of risk for exposure to CWD depending on the presence of various risk factors. Based on the assumption that areas of Virginia in proximity to concentrations of farmed or captive deer or elk are at the highest risk for the introduction of CWD into the free-ranging white-tailed deer population (Odocoileus virginianus), the Virginia Department of Game and Inland Fisheries (VDGIF) conducted a qualitative risk assessment that resulted in the stratification of the state into three risk categories (high, medium, and low risk) and the application of different surveillance strategies in each region.

Population reconstruction is a technique that uses harvest-at-age data and backward addition of cohorts to estimate minimum population size over time. Management agencies use population reconstruction because it uses data that are commonly collected for managed species, particularly for bear and deer populations. However, this technique had not been rigorously evaluated for accuracy or precision. We used computer simulations to evaluate the impact of life history parameters, harvest rate, sampling error, and violated assumptions on Downing population reconstruction estimates. This technique was robust to collapsing age classes if harvest rates for the oldest two age classes in the reconstruction were similar. Harvest and natural mortality rates were the driving factors in the accuracy of population reconstruction estimates. The technique was most accurate when harvest rate was high and natural mortality was low.

We investigated population densities and genetic structure of black bears at three national wildlife refuges (Great Dismal Swamp [GDSNWR], Pocosin Lakes [PLNWR], and Alligator River [ARNWR]). We derived density estimates from DNA samples collected noninvasively at each refuge for two consecutive summers. Hair samples were analyzed for individual identification using 6-7 microsatellite markers. Estimated densities were some of the highest reported in the literature and ranged from 0.56-0.63 bears/km2 at GDSNWR to 0.65-1.12 bears/km2 at ARNWR to 1.23-1.66 bears/km2 at PLNWR. Sex ratios were male-biased at all refuges. We also assessed genetic variability of bear populations at these refuges using 16 microsatellite markers for 40 bears at each refuge. Genetic variability was substantially high at all refuges compared to other bear populations in North America, with observed heterozygosities ranging from 0.6729 at GDSNWR to 0.7219 at ARNWR.

No paper was submitted with this abstract. Abstract was too long so please refer to pdf.