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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Factors influencing the winter survival of the bobwhite on the Virginia Polytechnic Institute college farms Montgomery County, Virginia

January 1948 (has links)
M.S.
22

Home range, habitat use, and movements of reintroduced masked bobwhite

Simms, Karen Maureen, 1961- January 1989 (has links)
Home range, habitat use, and movements of reintroduced masked bobwhite (Colinus virginianus ridgewayi) were studied during 1986-88 on the Buenos Aires National Wildlife Refuge in southern Arizona. Home ranges averaged 10.9 ha (5.2-14.6 ha), and core areas averaged 1.1 ha (0.2-2.7 ha). Core areas had significantly higher visual obstruction by vegetation from 0-1 dm, aerial and basal grass cover, and significantly lower bare ground, litter, half-shrub cover, half shrub density, and visual obstruction by vegetation from 5-20 dm than non-core areas. The majority of the masked bobwhite moved less than 1 km between their release location and the site of first trapping. However, some long distance movements occurred. Once home ranges were established, masked bobwhite seldom left the boundaries. Key habitat components are identified for masked bobwhite on the Buenos Aires National Wildlife Refuge.
23

An Exploration of Testosterone Mediated Effects on Auditory Learning in Northern Bobwhite Quail

Unknown Date (has links)
Elevated yolk progesterone has been shown to impair prenatal, but facilitate postnatal auditory learning in bobwhite quail chicks. Elevated yolk testosterone has facilitated prenatal learning, but its effects on postnatal auditory learning in quail are unknown. Either testosterone or an oil vehicle was injected into bobwhite quail eggs prior to incubation. Control eggs were unmanipulated. Following hatching, chicks were exposed to a conspecific maternal call (A or B) for 240 min. At 48 hr, chicks were tested for their preference for the familiarized vs. novel call. All groups demonstrated a preference for the familiar call (p < .05), but minimal between group difference were found. Contrary to previous research, elevated yolk testosterone neither facilitated nor impaired postnatal auditory learning in bobwhite quail chicks. Further research will examine underlying mechanisms responsible for differential effects and explore if similar systems are involved in other species-typical processes such as social motivation. / Includes bibliography. / Thesis (M.A.)--Florida Atlantic University, 2017. / FAU Electronic Theses and Dissertations Collection
24

Systems toxicology identifies mechanistic impacts of 2-amino-4, 6-dinitrotoluene (2A-DNT) exposure in Northern Bobwhite

Gust, Kurt A., Nanduri, Bindu, Rawat, Arun, Wilbanks, Mitchell S., Ang, Choo Y., Johnson, David R., Pendarvis, Ken, Chen, Xianfeng, Quinn, Michael J., Johnson, Mark S., Burgess, Shane C., Perkins, Edward J. January 2015 (has links)
BACKGROUND: A systems toxicology investigation comparing and integrating transcriptomic and proteomic results was conducted to develop holistic effects characterizations for the wildlife bird model, Northern bobwhite (Colinus virginianus) dosed with the explosives degradation product 2-amino-4,6-dinitrotoluene (2A-DNT). A subchronic 60d toxicology bioassay was leveraged where both sexes were dosed via daily gavage with 0, 3, 14, or 30 mg/kg-d 2A-DNT. Effects on global transcript expression were investigated in liver and kidney tissue using custom microarrays for C. virginianus in both sexes at all doses, while effects on proteome expression were investigated in liver for both sexes and kidney in males, at 30 mg/kg-d. RESULTS: As expected, transcript expression was not directly indicative of protein expression in response to 2A-DNT. However, a high degree of correspondence was observed among gene and protein expression when investigating higher-order functional responses including statistically enriched gene networks and canonical pathways, especially when connected to toxicological outcomes of 2A-DNT exposure. Analysis of networks statistically enriched for both transcripts and proteins demonstrated common responses including inhibition of programmed cell death and arrest of cell cycle in liver tissues at 2A-DNT doses that caused liver necrosis and death in females. Additionally, both transcript and protein expression in liver tissue was indicative of induced phase I and II xenobiotic metabolism potentially as a mechanism to detoxify and excrete 2A-DNT. Nuclear signaling assays, transcript expression and protein expression each implicated peroxisome proliferator-activated receptor (PPAR) nuclear signaling as a primary molecular target in the 2A-DNT exposure with significant downstream enrichment of PPAR-regulated pathways including lipid metabolic pathways and gluconeogenesis suggesting impaired bioenergetic potential. CONCLUSION: Although the differential expression of transcripts and proteins was largely unique, the consensus of functional pathways and gene networks enriched among transcriptomic and proteomic datasets provided the identification of many critical metabolic functions underlying 2A-DNT toxicity as well as impaired PPAR signaling, a key molecular initiating event known to be affected in di- and trinitrotoluene exposures.
25

Metabolizable energy in six foods and effect of diet on body fatty-acids in Bobwhites

Middendorf, Suzanne Marie January 2011 (has links)
Typescript (photocopy). / Digitized by Kansas Correctional Industries
26

The role of covey demographics in northern bobwhite (Colinus virginianus) production

Brooks, Jason Lee 16 August 2006 (has links)
Northern bobwhite (Colinus virginianus) populations are irruptive along their western periphery. Previous research has failed to identify the factors associated with these irruptions, but precipitation is often assumed to be a primary causal factor. I hypothesize that the mechanism may involve demographic variables, specifically that birds entering their second breeding season are more successful than subadult breeders. A better understanding of age-specific survival and productivity in quail populations may be beneficial if managing for a population with an older age structure could ameliorate the irruptive cycles. Radiotagged bobwhites (n > 100 each year; approximately equal numbers (25) of each age-sex class) were followed throughout the breeding season (Mar. – Aug.) in 2003 and 2004 in Fisher County, Texas. Survival, nesting attempts, hatch rate, and clutch size were monitored. Probability of survival of radiotagged birds during the breeding season was S = 0.465 and S = 0.395 in 2003 and 2004, respectively; survival was similar among all age-sex classes. Nest success was greater in 2004 (52.4%, n = 42) than 2003 (28.6%, n = 35) and the 2004 breeding season was at least 20 days longer, likely due to more summer rainfall and cooler temperatures. Nest success was similar among adult and subadult hens in 2003 (4 of 21 adult nests, 6 of 14 subadult nests) and 2004 (16 of 28 adult nests, 7 of 14 subadult nests). Nest initiation was similar in 2003 (0.84 nests/adult hen vs. 0.61 nests/subadult hen), but adults initiated more nests than subadults in 2004 (1.04 nests/adult hen vs. 0.58 nests/subadult hen). Adult hens initiated 12 of 15 renesting attempts observed. Nest initiation dates and nest site selection were similar between adults and subadults. The adult:subadult ratios for 2003 and 2004 were 1:3.0 and 1:1.3 (n = 426 and n = 224, respectively). Extrapolating from the sample population, subadults contributed approximately 84% of the chicks fledged in 2003 but only 37% in 2004, while adults contributed 16% and 63% in 2003 and 2004, respectively. Results from this study suggest that if covey demographics are a component of bobwhite irruptions, the mechanism is most likely due to greater renesting effort by adult hens.
27

Selected aspects of population dynamics and food habits of bobwhite quail on the Salamonie Reservoir area, 1970-1975

Priddy, Robert Ray January 1976 (has links)
Basic knowledge of the ecology of bobwhite quail, colinus virginianus (L.), on the Salamonie Reservoir Area, Huntington and Wabash Counties, Indiana, was gathered during 1970-1975. The bobwhite is a major gamebird species on the Salamonie Reservoir Area even though the resident populations of this non-migratory bird tend to remain relatively low. Bobwhites have been extensively studied in other parts of their range but little has been done in this marginal habitat region of northeastern Indiana. A basic knowledge of bobwhite ecology in this region is necessary in order to formulate management plans calculated to increase the population level.The whistling cock count technique was used to determine a call index from the average mean calls per stop. This technique correlated significantly with hunter success (P<0.05) but call indices from the highest count day, during the six-year period, correlated most significantly (P<0.001) with hunter success.An average of 50.2 percent cocks to 49.8 percent hens was found during the six-year study in 404 hunter-killed bobwhites and 36 bobwhites collected by me. Bobwhite weights averaged 179 g during the November months, 197 g during the December months, 205 g during the January months, and 185 g during the months of February and March. The mean average weight for the six-year study was 185 g. Age ratio, during the study months, was 3.66 young bobwhites to one adult. Age ratios were stable each November through March but they fluctuated annually during the six-year period with no consistant trend. Four major food items comprised 77.5 percent of volumetric contents found in bobwhite crops: corn, soybeans, wheat, and black locust seeds.Bobwhite population levels fluctuated during the six-year study. The population level appeared to have an inverse relationship with the number of small game hunting efforts on the Salamonie Reservoir Area when the small game hunting efforts numbered above 3,000.Bobwhites fed on black locust seeds during periods of snow cover. The availability of black locust seeds during winter months made this food source an important item for the survival of bobwhites on the Salamonie Reservoir Area.
28

INFLUENCE OF LANDCOVER ON NORTHERN BOBWHITE HOME RANGE AND SURVIVAL AT MULTIPLE SCALES IN SOUTHERN ILLINOIS

Crawford, Caleb Stanley 01 September 2021 (has links)
Northern bobwhite (Colinus virginianus) populations have continually declined across much of their native range due to changes in land use and habitat. This notable decline causes concern for the future of this important game bird species and highlights the need for research on how habitat influences bobwhite vital rates. My research, conducted during 2018-2020 at Burning Star State Fish and Wildlife Area, addressed the following two objectives to provide information on how landcover characteristics influence bobwhite populations: (1) investigate how landcover characteristics influence annual bobwhite home range size, and (2) investigate how landcover characteristics influence bobwhite breeding season survival. For Objective 1, I radio-marked 113 individuals of which 50 bobwhites (31 males and 19 females) had ≥25 independent tracking locations and were used in my analyses. I modeled landcover types related to bobwhite habitat selection, habitat avoidance, foraging habitat, and protective cover to annual bobwhite home range size. Landcover types related to foraging habitat formed the most parsimonious model, with the proportion of grassland having the greatest negative influence on bobwhite home range size. As expected, landcover types that are thought to be beneficial to bobwhite fitness were negatively related to bobwhite home range size, suggesting those landcover types provide necessary resources for bobwhites throughout their full annual cycle. For Objective 2, I radio-marked 113 individuals of which 50 bobwhites (31 males and 19 females) had ≥25 independent tracking locations and were used in my analyses. I used a known fate model of the influence of landcover types, in a stepwise fashion, on bobwhite breeding season survival at two scales, home range and landscape. At the home range scale, the univariate model including early successional forest was the most parsimonious model, wherein the proportion of early successional forest negatively influenced bobwhite breeding season survival. Other competitive models included agriculture and early successional forest + scrub shrub where agriculture positively influenced breeding season survival while early successional forest and scrub shrub negatively influenced breeding season survival. The negative influence of landcover types thought to provide necessary protective cover for bobwhites on breeding season survival is inconsistent with the current paradigm that woody cover is an important habitat component that provides protective and escape cover, thermoregulatory functions, and midday loafing sites for bobwhites. Early successional forest provides visually appealing woody protective cover but appears to expose bobwhites to a higher predation risk because trees provide perch habitat for avian predators. Agriculture positively influenced breeding season survival because during the breeding season, agriculture provides overhead cover and bare ground that provides protective cover, foraging opportunities, and enables ease of movement. At the landscape scale, the null model was the most parsimonious model, but there was weak evidence that the proportion of grassland positively influenced breeding season survival. My study demonstrates how landcover composition influences annual home range size and breeding season survival at different scales.
29

Using precision agriculture to identify overlap in conservation and economic opportunities in agricultural landscapes

Brister, Makayla 06 August 2021 (has links) (PDF)
Intense agriculture is detrimental to the environment and leads to nutrient runoff, decreased water quality, soil erosion, greenhouse gas emissions, and decreased wildlife habitat. In addition to negative environmental impacts, intense agriculture increases the financial strain on farmers. Farmers also face inconsistent yields from environmentally vulnerable lands. Due to these financial constraints and inconsistent yields, conservation goals are not always economically attractive to farmers and agricultural producers. One possible solution to this issue is the use of precision agriculture (PA) to inform strategic conservation efforts. We used PA technology to identify low-revenue field areas in the Mississippi Delta and Black Prairie regions. We created spatially explicit revenue maps and overlaid it with the Biologist Ranking Index (BRI) to illustrate where economic and conservation opportunities overlap. Our results indicate that, on average, upwards of 20.1% of the Black Prairie and 18.0% of the Mississippi Delta generate less revenue than conservation enrollment.
30

Northern bobwhite (Colinus virginianus) breeding season calling behavior and roost site selection in a working agricultural landscape in Clay County, Mississippi

Lappin, Olivia A 12 May 2023 (has links) (PDF)
Research on northern bobwhite calling behavior and roosting ecology during the breeding season has received limited attention. However, variability in calling rate in response to conspecifics and environmental factors may affect avian monitoring strategies. We conducted 10-minute breeding season surveys (April-August) on B. Bryan Farms, Mississippi, from 2021-2022 to evaluate the impact of conspecifics and environmental covariates on male bobwhite calling rate. We observed a positive linear effect of conspecifics and temperature on calling rate. We did not find sufficient evidence to support a relationship between calling rate and cloud cover or barometric pressure. We also analyzed breeding season third-order roost site selection and found selection against bare ground and a quadratic relationship with litter and average vegetation height during roosting activity. It is also important for managers to consider all conditions of the environment and habitat requirements during every season for population persistence, including breeding season roost cover.

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