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Habitat Assessment for Gopher Tortoise (Gopherus Polyphemus) and Grassland Birds in South MississippiStukey, Nathan Andrew 06 May 2017 (has links)
I studied eight habitat types of south Mississippi from 2009-2010 to examine habitat conditions and faunal communities associated with the presence of gopher tortoise burrows (Gopherus polyphemus). Field methods included burrow surveys, vegetation sampling, mound counts, and point count surveys. Active tortoise burrow presence was influenced by percent coverage of bare ground, native legumes, grass-like plants, basal area, overstory canopy, and woody plants. Fire ant mound densities were influenced by percent coverage of overstory canopy cover, bare ground, grass-like vegetation, and woody plants. Northern bobwhite (Colinus virginianus) and Bachman’s sparrow (Peucaea aestivalis) were detected more frequently in longleaf pine (Pinus palustris) dominated habitats supporting gopher tortoises. My findings will be used to address the paucity of information related to gopher tortoise conservation on private and public lands and identify potential areas for inclusion in conservation initiatives supporting longleaf pine restoration or gopher tortoise conservation in the southeastern lower coastal plain.
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Restoration Techniques for Northern BobwhitesNewman, William L. 05 1900 (has links)
Isolated populations of northern bobwhites (Colinus virginianus) have declined causing many quail managers to attempt population restoration by releasing captive-reared bobwhites or translocating wild bobwhites. I evaluated three restoration techniques: (1) release of captive-reared bobwhites, (2) translocation of bobwhites from high densities to low densities, and (3) release of captive-reared and translocated bobwhites acclimated on site prior to release. These results show that captive-reared birds have reduced survival and fewer nesting attempts when compared to translocated birds and that acclimation time was not a factor. I hypothesized that high mortality rates were caused by captive-reared birds exhibiting different predator avoidance behavior than wild birds. Captive-reared and wild-trapped bobwhites were subjected to independent predator simulations and their responses were recorded on high definition video. Threat recognition time, reaction type, and reaction time was recorded for comparative analysis. Pen-reared birds recognized the simulated raptorial and terrestrial predator threats quicker than wild-trapped birds, but reaction times were not different among groups. However, the type of reaction was different among groups where pen-reared birds typically flushed immediately upon recognizing either simulated predator as compared to wild-trapped birds which typically ran or held when subjected to the raptorial threat and showed little to no observable reaction to the terrestrial threat. These results reveal a potential loss of a holding trait in pen-reared birds, resulting in a quicker revealing of their position in the presence of a threat, thereby increasing their risk of predation.
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Population Dynamics of Northern Bobwhites in Southern TexasDemaso, Stephen 16 January 2010 (has links)
Northern bobwhites (Colinus virginianus) are an important cultural, ecological, and economical part of the southern Texas landscape. I used radio-telemetry data from 2000?2005, part of a long-term, bobwhite study in southern Texas, to test the nest-concealment hypothesis, develop a stochastic simulation model for bobwhite populations, and evaluate the influence of brush canopy coverage (BCC) on short- and long-term demographic performance of bobwhites.
Bobwhite nests tend to be situated in taller and denser vegetation than would be expected if nest-site location was a random process. I compared 4 microhabitat variables between successful (n = 135) and depredated nests (n = 118). I documented similar microhabitat attributes between successful and depredated nests. The discriminant function correctly classified only 48?59% of nest fates into the correct group, but only 18% of the variation in nest fate. Thus, my results did not support the nest-concealment hypothesis.
My stochastic simulation model for bobwhite populations is based on difference equations (?t = 3 months) and simulations run for 100 years using STELLA� 9.0.2. The probability of persistence for 100 years for the spring population was 74.2% and 72.5% for the fall population. Simulated population parameters were similar to those observed in the field for 5 of 6 population parameters. Only simulated male adult annual survival differed by 275.0% from field estimates. Despite this difference, my model appears to be a good predictor of bobwhite populations in the Rio Grande Plains of Texas.
I estimated bobwhite density, survival, and production (proportion of hens nesting, nesting attempts per hen, and clutch size) in 3 study areas with ~10%, ~25%, and >30% BBC. All demographic parameters were similar among the 3 BCC classes. However, simulation modeling indicated that long-term demographic performance was greater on the ~25% and >30% BCC classes. The probability of fall population persistence was greater in the ~25% (90.8%) and >30% (100.0%) BCC classes than in the ~10% BCC class (54.2%). My study highlights the shortcoming of considering only short-term effects when comparing habitat given that short- and long-term effects of habitat on demographic performance can differ.
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Effects of landscape configuration on northern bobwhite in southeastern KansasFlock, Brian E. January 1900 (has links)
Doctor of Philosophy / Department of Biology / Philip S. Gipson / Northern bobwhite (Colinus virginianus) populations in much of the species range have been declining for the last 35 years. I trapped and equipped bobwhite with radio transmitters and tracked them during 2003-2005. I used these data to examine the effects of landscape configuration on survival as well as the habitat association of bobwhite in southeastern Kansas. I used the nest survival model in Program MARK to determine the effects of habitat configuration on weekly survival of radio equipped bobwhite during the Fall-Spring (1 October to 14 April) and the Spring-Fall (15 April to 30 September) at home range and 500 m buffer scales. Individual survival probability for the Fall-Spring period was 0.9439 (S.E. = 0.0071), and the most parsimonious model for the Fall-Spring period at the home range scale was B0 + percent woodland + percent cropland. At the 500 m buffer scale the most parsimonious model was B0 + percent Conservation Reserve (CRP) program land. The weekly survival probability for the Spring-Fall period was 0.9559 (S.E. = 0.0098). At the home range and 500 m buffer scales there were weak associations of habitat to survival during Spring-Fall with the most parsimonious model for both scales B0 + percent other. Using Euclidean Distances to measure distance from animal location to each habitat, I found that habitat selection was occurring during the Spring-Fall (Wilkes λ = 0.04, F 6,36 = 143.682, P < 0.001) and Fall-Spring (Wilkes λ = 0.056, F 6, 29 = 81.99, P < 0.001). During Spring-Fall bobwhite were associated with locations near cool-season grasses and during Fall-Spring preferred locations near woody cover. Bobwhite also showed habitat selection at a second more refined land use classification level for Spring-Fall (Wilkes λ = 0.006, F 16, 26 = 284.483, P < 0.001) and Fall-Spring (Wilkes λ = 0.004, F 16, 19 = 276.037, P < 0.001). During the Spring-Fall, bobwhites were associated with locations near cool-season grass pastures and roads and during Fall-Spring were associated with locations in close proximity to roads and CRP. Understanding the effects of habitat configuration on bobwhite is an important step in developing a broad-scale management plan.
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Multi-Scale Response of Upland Birds to Targeted Agricultural ConservationEvans, Kristine Oswald 12 May 2012 (has links)
As human populations rise exponentially, agricultural production systems must be adapted to sustain ecosystem function. Government administered agricultural conservation programs may actualize greater gains in ecosystem services, including wildlife population gains, if conservation practices designed to target specific environmental outcomes are implemented strategically in agricultural landscapes. I evaluated multi-scale, multi-species, and multi-season avian population responses to a targeted native herbaceous buffer practice (CP33: Habitat Buffers for Upland Birds) under the continuous sign-up Conservation Reserve Program administered by the U.S. Department of Agriculture. CP33 is the first conservation practice targeted directly to support habitat and population recovery objectives of a national wildlife conservation initiative (Northern Bobwhite Conservation Initiative). I coordinated breeding season, fall, and winter point transect surveys for northern bobwhite (Colinus virginianus), priority early-succession, and overwintering birds on ≈1,150 buffered and non-buffered fields in 14 states (10 ecoregions) from 2006-2009. I also assessed northern bobwhite-landscape associations within each ecoregion to determine effects of landscape structure on observed northern bobwhite abundances. Breeding season and autumn northern bobwhite densities were 60-74% and 52% greater, respectively, over all survey points in the near term (1-4 years post-establishment). However, breeding season and autumn response and associations between northern bobwhite abundance and landscape structure exhibited substantial regional variation, suggesting northern bobwhite conservation and management should be implemented on a regional basis. Breeding season densities of dickcissel (Spiza americana) and field sparrow (Spizella pusilla) were up to 190% greater on buffered fields, whereas overwintering densities of several Emberizid sparrow species were up to 2,707% greater on buffered fields. Species sensitive to patch area or those requiring vegetation structure different from that provided by buffers exhibited limited, but regionally and annually variable responses to buffered habitats. Increased bird densities of several species in several seasons suggest wildliferiendly farming practices delivered strategically and requiring minimal change in primary land use can benefit species across broad landscapes when conservation practices are targeted toward specific recovery objectives. Targeted conservation systems combining multiple conservation practices to provide an array of ecosystem services may be a mechanism for meeting multifarious conservation objectives and enhancing biodiversity in agricultural landscapes.
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Landscape Level Evaluation of Northern Bobwhite Habitats in Eastern Virginia Using Landsat TM ImagerySchairer, Garrett L. 22 May 1999 (has links)
Northern bobwhite (<I>Colinus virginianus</I>) are important game birds associated with early successional habitats across the southeastern United States. In the past 30+ years there has been an almost universal decline in bobwhite population numbers despite a long history of management. The Virginia Bobwhite Quail Management Plan was implemented in 1996 to slow and stop the current population declines in Virginia. Virginia Department of Game and Inland Fisheries (VDGIF) personnel identified a lack of knowledge about the broad-scale, landscape level habitats in eastern Virginia. A large scale land cover map along with a detailed understanding of the spatial arrangements of bobwhite habitats will not only aid Virginia's management plan, but also allow focused efforts by our wildlife managers. I explored the possibilities of using remote sensing to map various habitats important to bobwhite. I compared several classification algorithms applied to Landsat TM imagery prior to selecting the classification method that best delineated early successional habitats. After method selection, a classified land cover map for the Coastal Plain and Piedmont of Virginia was generated.
Using the classified images available from the first part of the study and 4 years of bobwhite call count data, I studied the landscape level habitat associations of bobwhite. A number of landscape metrics were calculated for the landscapes surrounding bobwhite call count routes and were used in two modeling exercises to differentiate between high and low bobwhite populations. Both pattern recognition (PATREC) and logistic regression models predicted levels of bobwhite abundance satisfactorily for the modeled (84.0% and 96.0% respectively) and independent (64.3% and 57.1%, respectively) data sets. The models were applied to remotely-sensed habitat maps to develop prediction maps expressing the quality of a landscape for supporting a high population of bobwhite based on existing land cover.
Finally, I explored the possibility of eliminating the time consuming and very costly step of classifying a remotely-sensed image prior to examining its quality for a particular species. Using raw Landsat TM imagery and bobwhite call count data, I developed predictive logistic regression models expressing the quality of a landscape surrounding a pixel. The first model predicted the probability of the landscape supporting a high bobwhite population. Due to a number of stops with an average of zero, I was also able to generate a model that expressed the probability of the landscape supporting any number of bobwhite. This method also satisfactorily predicted high/low population and presence/absence for the modeled data (65.7% and 83.1%, respectively) and independent data (65.3% and 83.7%, respectively). The method described will allow for rapid assessment of our wildlife resources without having to classify remotely-sensed images into habitat classes prior to analyses. / Master of Science
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Effects of Prenatal and Early Postnatal Exposure to Aversive Stimuli on Fearfulness and Exploratory Behavior in Bobwhite Qauil Neonates (Colinus virginianus)Suarez, Michael 28 October 2014 (has links)
Neophobia, the fear of novelty, is a behavioral trait found across a number of animal species, including humans. Neophobic individuals perceive novel environments and stimuli to have aversive properties, and exhibit fearful behaviors when presented with non-familiar situations. The present study examined how early life exposure to aversive novel stimuli could reduce neophobia in bobwhite quail chicks. Experiment 1 exposed chicks to a novel auditory tone previously shown to be aversive to naïve chicks (Suarez, 2012) for 24 hours immediately after hatching, then subsequently tested them in the presence of the tone within a novel maze task. Postnatally exposed chicks demonstrated decreased fearfulness compared to naïve chicks, and behaved more similarly to chicks tested in the presence of a known attractive auditory stimulus (a bobwhite maternal assembly call vocalization). Experiment 2 exposed chicks to the novel auditory tone for 24 hours prenatally, then subsequently tested them within a novel maze task. Prenatally exposed chicks showed decreased fearfulness to a similar degree as those postnatally exposed, revealing that both prenatal and postnatal exposure methods are capable of decreasing fear of auditory stimuli. Experiment 3 exposed chicks to a novel visual stimulus for 24 hours postnatally, then subsequently tested them within a novel emergence box / T-maze apparatus. Chicks exposed to the visual stimulus showed decreased fearfulness compared to naïve chicks, thereby demonstrating the utility of this method across sense modalities. Experiment 4 assessed whether early postnatal exposure to one novel stimulus could generalize and serve to decrease fear of novelty when chicks were tested in the presence of markedly different stimuli. By combining the methods of Experiments 1 and 3, this experiment revealed that chicks exposed to one type of stimulus (auditory or visual) demonstrated decreased fear when subsequently tested in the presence of the opposite type of novel stimulus. These results suggest that experience with novel stimuli can moderate the extent to which neophobia will develop during early development.
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Usable Space and Microhabitat Characteristics for Bobwhites on Private Lands in Southwestern OhioWiley, Mark Joseph 31 August 2012 (has links)
No description available.
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Spatial Analyses of Northern Bobwhite Occupancy and White-tailed Deer Hunter Distribution and Success in OhioSforza, Stephanie A. 22 July 2022 (has links)
No description available.
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Quantifying the economic impact of conservation policy changes utilizing precision agriculture toolsWatkins, Kyle Stanley 13 May 2022 (has links) (PDF)
The United States Farm Bill is a multi-billion-dollar federal legislation reenacted every five years to provide funding towards crop protection, nutrition, environmental protection, and other important focuses. The largest conservation program within the Farm Bill is the Conservation Reserve Program, which encompasses many conservation practices such as CP-33: habitat buffers for upland birds. Conservation implementation through the Farm Bill relies on voluntary producer enrollment in exchange for a rental fee to not farm enrolled land for a set time. I used yield data collected across six years from 36 agricultural fields in Humphreys and Holmes counties, Mississippi, USA, and a range of commodity prices to compare the change in economic and environmental opportunities available through economically targeted conservation enrollment between the 2014 Farm Bill and the 2018 Farm Bill. I found the 2014 Farm Bill was consistently higher in economic revenue and conservation opportunity compared to the 2018 Farm Bill
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