Journal of the Southeastern Association of Fish and Wildlife Agencies

Two named subspecies of sheepshead exist in the northeastern Gulf of Mexico (Archosargus probatocephalus probatocephalus and A. p. oviceps). These subspecies are morphologically distinctive; previously published data was used to demonstrate that frequency distributions of each of five meristic counts are significantly different between the subspecies (P < 0.05). However, genetic characteristics suggest limited divergence. For instance, Bayesian structure analysis of microsatellite genotypes indicated that all sampled populations of Gulf of Mexico sheepshead constitute a single stock, with a posterior probability of P ∼− 0.9999. Variance partitioning of mtDNA haplotypes suggests significant but limited divergence between subspecies (Fst = 0.036, P < 0.005), but isolation by distance, rather than subdivision among discreet genetic stocks, is likely driving the significance of variance analyses.

In May 2006, the Texas Parks and Wildlife Department enacted a regulation which prohibits the uprooting of seagrasses by propellers within the Redfish Bay State Scientific Area (RBSSA) located in Aransas and Corpus Christi Bays, Texas. Two complementary studies were implemented to evaluate the efficacy of the new regulation and to quantify the magnitude of propeller scarring. In the first study, 35 randomly-selected 100-m transects were established and the total number of propeller scars on each transect were recorded annually, with qualitative and quantitative information collected on each scar. Following enactment of the regulation, significantly fewer scars (69%) were observed (P < 0.0001). Prop scars recovered rapidly; of the 97 scars observed in 2006, 91 were considered recovered in 2007. In the second study, high resolution aerial imagery (0.1 m) was acquired in spring 2006 and 2007 and estimates of scarring were generated using automated feature extraction methods.

The Texas Parks and Wildlife Department's saltwater creel survey is conducted at boat-access sites from 1000 to 1800 hours. Fishing trips concluding outside of this time period are not intercepted. In particular, nighttime fishing trips concluding before 1000 hours are not intercepted, but these trips seasonally target specific fisheries, e.g., southern flounder (Paralichthys lethostigma) in the fall, which may account for a significant portion of the total harvest. We re-evaluated the 1000 to 1800 hour survey period and monitored nighttime boating activity at boat-access sites with surreptitiously placed “trail cams.” These cameras were used coastwide from October through December 2007 to hourly record empty trailers parked at boat ramps used most often by nighttime flounder anglers. A total of 2,135 usable images captured 11,520 empty trailers, with the highest counts occurring between 0700 and 1800 hours. Boat ramp use declined from October to December.

Since the inception of Texas' Abandoned Crab Trap Removal Program in 2002, volunteers and Texas Parks and Wildlife Department (TPWD) staff have removed 24,047 abandoned crab traps from the coastal waters of Texas. From 2002-2007 TPWD staff collected data from a minimum of 30 traps from each coastal ecosystem, recording numbers and species of organisms observed, trap condition, location, and presence of trap owner identification, escape rings, and degradable panels. A total of 1,703 traps were studied. Forty-one species of organisms were observed with the majority (53%) made up of blue crab (Callinectes sapidus), followed by Gulf stone crab (Menippe adina) 21%, sheepshead (Archosargus probatocephalus) 8%, and Gulf toadfish (Opsanus beta) 3%. Extrapolating the annual catch rate to the total number of traps removed each year, a potential total of 47,201 organisms would have been observed.

Between 1985 and 2007, Texas Parks and Wildlife conducted a trawl survey in the Texas Territorial Sea, extending from the beach out to 16.7 km and within 24.1 km on either side of passes at Sabine Pass, Galveston, Matagorda, Aransas Pass, and Brazos-Santiago Pass, where sampling occurred in an area 48.2 km north from the Texas-Mexico border. All samples were within NMFS statistical zones 17-21. Random sample locations were stratified by Gulf area and 16 month-1 stratum-1 were collected (n = 21,353). Mean total length (TL) of red snapper (Lutjanus campechanus) was 90 mm (± 0.31 SE, n = 7,688). Coastwide mean catch h-1 (CPUE) was 2.1 (± 0.11 SE), although catch rates were low along the northern Texas coast with only 16.6% of red snapper CPUE from Sabine Pass to Matagorda (zones 17-19). Aransas Pass (zone 20) and Brazos-Santiago Pass (zone 21) dominated red snapper catches with 43.8% and 39.6% of total CPUE, respectively.

America's boaters and anglers need to be fully engaged in the aquatic invasive species (AIS) issue. In the United States, there are 12.7 million boaters and 40 million anglers. If they are unaware of the AIS issue and do not know what to do, they pose great threats for the spread of harmful invasive fish, plants, and other organisms. While research shows they are part of the problem, the good news is they are willing to be part of the solution. Several studies show they are willing to take action with the understanding that our waters are too valuable to allow them to be invaded. To address this issue, Stop Aquatic Hitchhikers! campaign partners teamed up with the Threat Campaign, led by Wildlife Forever, to expand the prevention message across the country to enlist an army of support in the battle against aquatic hitchhikers. Linking the Stop Aquatic Hitchhikers!

By the early 1990s, boat propeller scars were causing significant damage to seagrass beds in Redfish Bay, Texas. Efforts initiated by Texas Parks and Wildlife Department (TPWD) to address the problem began in 2000 with the designation of Redfish Bay as a State Scientific Area (RBSSA). An education and outreach program was initiated and three voluntary no-prop zones were established. However, these efforts were largely unsuccessful. Public comments made to the Texas Parks and Wildlife Commission in 2005 indicated a strong desire by constituents to see a more effective education and outreach program in addition to any regulatory decree. In May 2006 a regulation went into effect which prohibited the destruction of seagrasses by boat propellers without precluding access to the area. In order to make user groups aware of the new regulation and the importance of seagrasses, an extensive outreach and education campaign began in January 2006.

Fishery-dependent and fishery-independent surveys indicate the southern flounder (Paralichthys lethostigma) population along the Texas coast is declining. An analysis of water temperature indicates a negative correlation between flounder recruitment and winter temperatures. Years with warmer winter water temperatures result in low flounder recruitment, while years with cooler winter water temperatures yield higher recruitment. This effect is pronounced on the lower coast of Texas, from San Antonio Bay to the lower Laguna Madre, where higher water temperatures occur, and after 1991, when winter water temperatures increased up to 5 C above average. Possible explanations include direct effects, such as a decrease in hatching success as temperatures rise, and indirect effects, such as increased predation on flounder larvae and early juveniles when higher temperatures are present.

To assess the role of oyster reef as finfish habitat in Texas' estuarine systems, species abundance and diversity differences were compared between shoreline habitats and mid-water oyster reefs in East Matagorda Bay, Texas. Texas Parks and Wildlife 183-m gill nets were deployed overnight for a 10-week period during both spring and fall at oyster reef habitat (one net per week) and shoreline habitats (two nets per week). Metrics used to evaluate each habitat type included abundance, diversity, length and gender. Results indicate significant differences in abundance and diversity of sub-adult and adult finfishes among habitat treatments. Additionally, differences between spotted seatrout gender ratios (Cynoscion nebulosus) on oyster reefs versus shoreline habitats were observed with a greater proportion of male spotted seatrout found on oyster habitat.

Lake Conroe has long been synonymous with controversial control of the exotic plant hydrilla (Hydrilla verticillata). Hydrilla was first identified in Lake Conroe in 1975, only two years after the reservoir was impounded. By the time it was identified in Lake Conroe hydrilla already occupied 190 ha. Subsequent surveys indicated hydrilla was spreading rapidly. By 1979, hydrilla had increased to over 1,821 ha in Lake Conroe and was causing significant problems for boaters, skiers, and swimmers. As a result of efforts by the Lake Conroe Association and its supporters and despite objections by Texas Parks and Wildlife Department (TPWD) staff, the Texas Legislature directed the Texas Agricultural Experiment Station (now Texas AgriLife Extension Service) and TPWD to conduct a study to determine the efficacy, and other effects of grass carp use in Lake Conroe.

Lake Conroe is located approximately 93 km north of Houston, Texas, on the west fork of the San Jacinto River in Montgomery and Walker counties. Constructed in 1973 as a joint project of the City of Houston, the Texas Water Development Board, and the San Jacinto River Authority (SJRA) to serve as an alternate water source for the City of Houston, the reservoir covers about 8,498 ha. An expanding problem with the invasive plant hydrilla (Hydrilla verticillata) in 2006 prompted the creation of the Lake Conroe Vegetation Management Plan. The Texas Parks and Wildlife Department and SJRA developed the plan in cooperation with local homeowners, business owners, anglers, and other recreational users. The plan called for the reduction of hydrilla coverage to 16 ha or less by March 2008 by means of integrated pest management while protecting and enhancing the native aquatic plant community in Lake Conroe. In order to support the plan's overall goal the Seven Coves Bass Club (a B.A.S.S.

Angler surveys along with other modern research techniques provide managers with information needed to justify regulations to protect resources, to increase resources through stocking and habitat improvement, and to justify access improvement. However, Texas Parks and Wildlife (TPWD) receives little or no information from anglers concerning their activities on the majority of public waters. An online angler diary (OAD) system could substantially increase the number of water bodies from which TPWD receives at least anecdotal angler information. In order to create an efficient means of collecting and sharing angler data, the Inland Fisheries Division has asked the Resource Information System (RIS) team to create the OAD as a web-based application.

The striped skunk (Mephitis mephitis) is widely distributed in North America and a common inhabitant of urban areas. Striped skunks represent a reservoir and vector for the transmission of diseases that pose a significant human health risk, including rabies and the parasite Toxoplasma gondii. Therefore, understanding population structure and movements among striped skunk populations will assist in the management of disease issues within urban landscapes. Here we present a spatial analysis of striped skunk population structure within greater Houston, Texas, based on 7 microsatellite DNA markers amplified in 102 adult striped skunks. Although this highly developed urban landscape is bisected by major highways with high traffic volume (including Interstate 10 and US Hwy 59), we found no evidence for unique genetic clusters that might indicate barriers to dispersal. We detected weak genetic structure over the entire data set (FST = 0.031, P < 0.001).

Northern bobwhite (Colinus virginianus) populations are continuing a 30-year downward population trend throughout their range. Managers use supplemental corn (Zea mays) and milo (Sorghum spp.), trying to reverse the decline of bobwhite populations; however, results are conflicting among the published literature. Supplemental feed can influence bobwhite survival, reproduction, and movements, but only in situations where nutrients are truly lacking. Vitamin A, phosphorus (P), calcium (Ca), carbohydrates, and protein can be important nutrients for captive bobwhite egg production; however, controlled experiments are necessary to determine the impact of these nutrients on wild bobwhite populations.

Long-term population declines and conservation concerns resulting from large scale habitat loss have brought into question the biological justification of fixed, liberal harvest regulations as they apply to new world quail (Odontophoridae). As available quail habitat declines, biologically justifiable and sustainable methods of harvest will become essential components of quail management. Two hypotheses, the doomed-surplus hypothesis and the additive mortality hypothesis, attempt to provide a conceptual framework regarding the nature of mortality in hunted populations (i.e., compensatory vs. additive, respectively). Recent research indicates that harvest mortality is at least partially additive, which suggests that a strategy of sustained-yield harvest management may be more appropriate than fixed, liberal harvest regulations for quail populations.

There is growing concern about the impacts that exotic grasses may have on northern bobwhite (Colinus virginianus) and other grassland birds. Large areas of South Texas have been seeded to or have been invaded by several species of exotic grasses including Guinea grass (Urochloa maxima), Bermuda grass (Cynodon dactylon), King Ranch bluestem (Bothriochloa ischaemum), Kleberg bluestem (Dichanthium annulatum), buffelgrass (Pennisetum ciliare), and Lehmann lovegrass (Eragrostis lehmanniana). Impacts of exotic grasses on northern bobwhite are largely unknown. While exotic grasses such as buffelgrass have the potential to provide roosting and nesting habitat for northern bobwhite, landscapes dominated by invasive exotic grasses are potentially detrimental to bobwhite habitat because of the negative impact these grasses may have on diversity and abundance of native herbaceous vegetation and arthropod communities.

Ecologically sound habitat management will be essential to reverse the current decline of grassland birds. The objective of this study is to evaluate the effects of two habitat management practices: (1) summer prescribed fire [SF], (2) a combined treatment of roller chopper, summer prescribed fire, and chemical application [CT], and (3) an open grassland [C] as “control” on wintering grassland-shrub bird community composition and abundance. Line transects of variable lengths were used to assess the bird community structure. Grassland bird species richness during first season was 31 and 15 species on summer fire and combined treatment, respectively. Compared to the first season, species richness on second and third season decreased 1.3 and 2.4 times, respectively, on SF, whereas on CT it increased and decreased 1.7 and 1.1 times during second and third season, respectively.

To ascertain potential ecological and landowner benefits of non-conventional agricultural systems, this project was designed to monitor cattle production and wildlife utilization of land areas that allow grazing cattle to harvest corn planted with no-till methods. In 2005-2008, study sites were located in four Mississippi counties, including four steer/heifer-grazed and harvested corn fields (SHS) and four conventionally-managed and combine-harvested corn fields (CHS). Forest wildlife species, such as white-tailed deer (Odocoileus virginianus), utilize agricultural areas as foraging habitat consuming residual grain left behind by non-conventional and mechanical harvesters (Graham 2000). When conducted properly, camera survey estimates provide adequate results in all habitat types (Jacobson 2002).

Aboveground vegetation of many species of submerged aquatic plants is an important food source for many species of waterbirds adapted to a diet high in fiber. Wigeongrass (Ruppia maritima), a submerged aquatic plant inhabiting estuarine wetlands, has been documented as an important winter food for waterbirds along the Texas Gulf Coast. Thus, we examined availability of wigeongrass at Mad Island Wildlife Management Area (MIWMA), Texas, by estimating aboveground biomass from October through January 1998-99 and 2001-02. We also used an exclosure experiment to determine the extent to which herbivory by waterbirds was responsible for depletion of wigeongrass. Aboveground biomass of wigeongrass varied between years, among months, and among months within each year (interaction term). Biomass of wigeongrasss declined an average of 189 g m2 -1 and 71 g m2 -1 between October and January each year. Aboveground biomass also was influenced by the effect of exclosures within month.

The Fishes of Texas database compiled by the Texas Natural History Collection at the University of Texas at Austin consists of 65,876 freshwater records vouchered by specimens curated at 34 U.S., Mexican, and European collections, many unavailable online or in computerized format. An estimated 95% of all fish specimens ever collected in Texas since 1854 are represented, as are all known Texas freshwater species. All but 28 of Texas' 254 counties are represented in the 20,664 total localities, all now manually georeferenced. Locality plots reveal significant spatial gaps, and temporal distribution of sampling is similarly uneven, peaking in 1950-1970 then sharply declining. Post 1980, 27% of counties were not sampled at all and 90% were sampled <20 times. Clearly this database does not provide a current perspective on the state's fish fauna, but just as clearly it provides the best historic data ever available.

Aquatic vegetation plays an important role in freshwater systems, providing quality habitat for fish, sequestering nutrients, stabilizing sediments, and improving water clarity. Because many Texas reservoirs are either sparsely vegetated or contain an overabundance of non-native species such as hydrilla (Hydrilla verticillata), Texas Parks and Wildlife Department's Inland Fisheries Division began a new initiative to develop procedures for establishing diverse native aquatic plant communities. Establishment techniques were tested in seven reservoirs representing diverse geographical areas from 1998 through 2003. Aquatic plant species native to Texas and representing three growth forms (submersed, floating-leaved, and emergent) were used. Plant survival and spread was documented using GIS technology. Results were variable; however, founder colonies capable of long-term propagule production and spread were established in all seven reservoirs.

The ultimate success of natural resource decision-making depends upon knowledge gathered from several sources; e.g. biological data, institutional values and beliefs, and human dimensions information from affected constituents. Handfishing for catfish has been at the forefront of Missouri conservation since 2000. To determine the acceptability of handfishing to Missouri anglers we conducted a survey of licensed anglers in 2004. The objective of this study was to examine the effects of survey question wording on angler response and the potential for different policy outcomes resulting from the different wording. We designed two versions of a survey to gauge angler support for legalizing handfishing and to determine what impact, if any, different question wording had on levels of support for handfishing. Version 1 resulted in a 33% level of support for legalizing handfishing, while Version 2 resulted in 50% support.

Catfish managers and researchers were asked to participate in an online survey describing current information needs, sampling techniques, and known gear biases for projects during 2002-2006. One hundred eighty two responses were collected in a four-month period in early 2006. Channel catfish (Ictalurus punctatus) were the most targeted species, followed by flathead (Pylodictis olivaris) and blue (I. furcatus) catfish, respectively. A variety of methods were used to collect catfishes. Flathead and blue catfish were most often sampled by low-frequency electrofishing (30 Hz or less), whereas channel catfish were often sampled with a variety of gears. Sixty-one percent of respondents indicated a need for information concerning sampling gear efficiency and gear bias. Limited quantitative information exists regarding bias of gears used to sample catfish, especially low-frequency electrofishing.

Yellow perch (Perca flavescens) is recognized as a widely distributed and valuable freshwater species, but few reports have described estuarine populations in coastal river systems. We conducted a two-year study to assess the age, growth, mortality, and fecundity of yellow perch in Albemarle Sound, North Carolina. Fish were collected (n = 2,674) in 2005 and 2006 (January-February) by trap from Yeopim River, Yeopim Creek, and Bethel Creek. Yellow perch ranged in age from 1-9 years, and the catch was dominated by age-2 fish (82.1%) in 2005 and age-3 fish (84.2%) in 2006. Lengths ranged from 130 to 292 mm TL (meanfemale = 231.1 ± 3.3 S.E. mm TL; meanmale = 177.8 ± 12.1 mm TL). Length distribution and age frequency data suggest that 2003 was a successful year class for yellow perch in Albemarle Sound. Instantaneous total mortality (Z) was 0.35 (annual mortality 30%), and was similar to estimates from Chesapeake Bay.