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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.
1

ASSESSMENT AND SPATIAL ANALYSIS OF BOBCAT PARASITES IN SOUTHERN ILLINOIS

Hiestand, Shelby Jane 01 August 2013 (has links)
Bobcats (Lynx rufus) are the most abundant and widely-distributed wild felid species in North America. The current increase of population densities of bobcats raises concerns about their importance as reservoirs of pathogens and parasites that may affect the wildlife community. Although many parasites found in bobcats also infect other wild and domestic animals, knowledge of bobcat parasites and potential impacts on other species has received relatively little attention. My objectives were to determine the endoparasite species present in Illinois bobcats, compare them to previous records in the United States, and predict their potential presence in southern Illinois using the program MAXENT. To complete these goals, necropsies were performed on 67 road-killed or trapped bobcats collected during 2003-12. I found infections caused by cestodes, nematodes, and trematodes including Taenia rileyi (70.1%), Toxocara cati (25.3%), and Alaria marcianae (41.7%). The highest mean abundance was found for Alaria marcianae (81) followed by Taenia rileyi (4) and Toxocara cati (3). Alaria marcianae had the highest intensity (193) with a range of 1-2,872. The comparison of parasite communities across 10 geographic locations using Jaccard's similarity index showed low similarity among all regions with the most similar community between Nebraska and Texas (0.53) and Arkansas being the most similar to southern Illinois (0.74). Parasite presence data were then used with environmental data layers of water, soil, land cover, human density, and climate variables in MAXENT to create maps of potential presence of 3 parasite species in a 46,436-km2 portion of southern Illinois. Precipitation of seasonality, the change of average rainfall seasonally, and average precipitation were the highest contributing variables used by MAXENT when creating probability maps of Taenia rileyi (55.1%) and Alaria marcianae (58.4%). For Toxocara cati land cover (40.6%) and soil (27.6%) were the highest contributing variables. With the addition of a sampling bias layer (i.e., bobcat presence) all climatic variables were low contributors (0.0-2.0%) while land cover remained important for Alaria marcianae (7.6%) and Toxocara cati (6.3%); human density (4.8%) was of secondary importance for Taenia rileyi after including the bias layer. Variables of importance likely represent habitat requirements necessary for the completion of parasite life cycles. Larger areas of potential presence were found for generalist parasites such as Taenia rileyi (85%) while potential presence was less likely for parasites with complex life cycles such as Alaria marcianae (73%). My study provides information to wildlife biologists and health officials regarding the potential impacts of growing bobcat populations in combination with complex and changing environmental factors.
2

Urban Bobcat (Lynx rufus) Ecology in the Dallas-Fort Worth, Texas Metroplex

Golla, Julie M. 01 December 2017 (has links)
Urban landscapes are quickly replacing native habitat around the world. As wildlife and people increasingly overlap in their shared space and resources, so does the potential for human-wildlife conflict, especially with predators. Bobcats (Lynx rufus) are a top predator in several urban areas across the United States and a potential contributor to human-carnivore conflicts. This study evaluated the movements and habitat use of bobcats in the Dallas-Fort Worth (DFW), Texas metroplex. Spatial data were collected from 10 bobcats via Global Positioning Satellite (GPS) for approximately one year. Average home range size was 4.60 km2 (n=9, SE=0.99 km2) for all resident bobcats, 3.48 km2 (n=5, SE=1.13 km2) for resident females, and 6.00 km2 (n=4, SE=1.61 km2) for resident males. Resource selection function (RSF) models show that bobcats avoid areas close to and far from grasslands and low-medium development, while selecting for these areas at intermediate distances. Bobcats also selected areas closer to developed open space, agricultural areas, and railroads. In addition, camera trap data analyzed with spatially explicit capture-recapture (SECR) models informed by the RSF results estimated a population density of 0.64 bobcats/km2 (SE = 0.22). Bobcats in DFW have significantly smaller home ranges and occur at higher densities compared to rural bobcat populations. Home ranges were also slightly smaller and densities higher than the most closely similar peri-urban bobcat studies. These differences likely arise due to the abundant urban prey species the DFW landscape provides despite limited space and habitat for bobcats. The dense urban development surrounding this population of bobcats may also discourage dispersing from the area, and contributing to higher densities. These results provide information to facilitate management of urban bobcats by providing new insight into how bobcats live amidst people in urban areas.
3

Bobcat Abundance and Habitat Selection on the Utah Test and Training Range

Muncey, Kyle David 01 December 2018 (has links)
Remote cameras have become a popular tool for monitoring wildlife. We used remote cameras to estimate bobcat (Lynx rufus) population abundance on the Utah Test and Training Range during two sample periods between 2015 and 2017. We used two statistical methods, closed capture mark-recapture (CMR) and mark-resight Poisson log-normal (PNE), to estimate bobcat abundance within the study area. We used the maximum mean distance moved method (MMDM) to calculate the effective sample area for estimating density. Additionally, we captured bobcats and estimated home range using minimum convex polygon (MCP) and kernel density estimation (KDE) methods. Bobcat abundance on the UTTR was 35-48 in 2017 and density was 11.95 bobcats/100 km2 using CMR and 16.69 bobcats/100 km2 using PNE. The North Range of the study area experienced a decline of 36-44 percent in density between sample periods. Density declines could be explained by natural predator prey cycles, by habituation to attractants or by an increase in home range area. We recommend that bobcat abundance and density be estimated regularly to establish population trends.To improve the management of bobcats on the Utah Test and Training Range (UTTR), we investigated bobcat (Lynx rufus) habitat use. We determined habitat use points by capturing bobcats in remote camera images. Use and random points were intersected with remotely sensed data in a geographic information system. Habitat variables were evaluated at the capture point scale and home range scale. Home range size was calculated using the mean maximum distance moved method. Scales and habitat variables were compared within generalized linear mixed-effects models. Our top model (AICc weight = 1) included a measure of terrain ruggedness, mean aspect, and land cover variables related to prey availability and human avoidance.
4

Relatedness Assessment and Analysis of Road Mortality Effects on <i>Lynx rufus</i> in Ohio

Heffern, William J. 10 September 2021 (has links)
No description available.
5

Assessment of the Lactation Index for Managing White-Tailed Deer Populations

Campbell, Kamen Lee 11 August 2012 (has links)
I analyzed precision and accuracy of lactation data to reflect actual fawn recruitment for various levels of fecundity, neonatal mortality, harvest intensity, and hunter selectivity. I evaluated and developed a correction equation to adjust for harvest date effects on lactation detectability. I compared metrics of site-specific fawn recruitment (e.g., lactation rates, hunter observation fawn-to-doe ratios, and post-season fawn-to-doe ratios) among themselves, and to site-specific indices of carnivore abundance, for 18 properties across Mississippi and Alabama. Accuracy of lactation rates are compromised due to variation at minimal harvest intensity and insensitivity to change in fetal rate or neonatal mortality. Lactation data can be corrected for harvest date effects on lactation detectability. Hunter observation data are variable and poorly represent fawn recruitment. Lactation data are related to fawn recruitment and can be used to roughly estimate fawn recruitment. Carnivore abundance had neither a significant nor consistent effect on fawn recruitment.
6

Bobcat and coyote management scenarios: evaluating the flexibility of management preferences in probable scenarios

Stanger, Melissa Eileen 26 October 2022 (has links)
No description available.
7

Factors Affecting White-tailed Deer Recruitment in Virginia

Aubin, Gisele Rosalie 12 June 2020 (has links)
Deer (<i> Odocoileus </i> spp.) are an important cultural and economic resource. They are the most popular game species in the United States and the number one driver of conservation funding. On the other hand, they also cause damage to resources including to the agricultural industry, private property and to humans via deer vehicle collisions. Many areas in eastern North America have experienced a decline in white-tailed deer (<i> Odocoileus virginianus </i>) populations over the past twenty years concurrent with changes in landscape, deer harvest strategies, and increasing and expanding black bear (<i> Ursus americanus </i>) and coyote (<i> Canis latrans </i>) populations. Most studies have addressed this problem at small spatial and temporal scales and in areas where predation was assumed to be limiting population growth. We evaluated white-tailed deer fawn recruitment both directly and indirectly at relatively broader spatial and temporal scales. We studied fawn survival on Marine Corps Base Quantico in Virginia, USA from 2008–2019. We used the Kaplan-Meier estimator, and Cox-proportional hazards models to assess annual survival and factors that influence hazard risk such as sex, weather, landscape composition and configuration and food availability. On Marine Corps Base Quantico, we found an increase in red oak mast abundance increases survival and probability of fawn survival was higher during the first interval of the study (2008–2010; 0.71 [0.52–0.96]; survival probability [CI95%]) than the last three intervals (2011–2013; 0.46 [0.30–0.70]; 2014–2016; 0.48 [0.35–0.66] and 2017–2019; 0.50 [0.39–0.63]). We also found that predation was the leading source of mortality. We assessed recruitment using lactation status from hunter harvest data collected by the Virginia Department of Game and Inland Fisheries during a 22-year period in 30 counties in the Appalachian Mountains of western Virginia. We predicted lactation status as a function of landscape composition and configuration, oak mast abundance, weather, age, and predator detection rates using generalized linear mixed models. We found land cover diversity index positively and black bear detection rate negatively influenced recruitment. Age also predicted lactation status with middle-aged females (3.5–4.5 years old) having a higher lactation probability than mature (≥5.5 years old) age and young (2.5 years old) age class deer. Based on these findings, recruitment is likely to be greater in areas that are heterogeneous. Therefore, if an increase in recruitment is desired silvicultural practices such as fire and timber harvest could be used to permanently change land cover types. These silvicultural practices could also be used to increase the number of oaks on the landscape, and augment production of mature oaks as red oak mast abundance influenced fawn survival. Also reducing predation by manipulating predator densities could improve recruitment. Another potential option which needs further research, would be to reduce predator efficiency by increasing hiding cover for fawns. / Master of Science / Deer (<i> Odocoileus </i> spp.) are an important cultural and economic resource. They are the most popular game species in the United States and the number one driver of conservation funding. Conversely, they also cause damage to resources including to the agricultural industry, private property and to humans via deer vehicle collisions. Some areas in eastern North America have experienced a decline in white-tailed deer (<i> Odocoileus virginianus </i>) populations over the past twenty years concurrent with the colonization of coyotes (<i> Canis latrans </i>) as well as changes in habitat. Therefore, we aimed to determine white-tailed deer fawn survival rates and factors affecting recruitment across a large spatial and temporal scale. Recruitment is when an individual becomes part of the reproductive population. However, for harvestable populations, recruitment is when individuals can be legally harvested for the first time. On Marine Corps Base Quantico from 2008–2019, in Virginia, USA we found that probability of fawn survival was higher during the first interval of the study (2008–2010; 0.71 [0.52–0.96]; survival probability [CI95%]) than the last three intervals (2011–2013; 0.46 [0.30–0.70]; 2014–2016; 0.48 [0.35–0.66] and 2017–2019; 0.50 [0.39–0.63]). We also discovered predation was the leading cause of death and probability of survival increased with increasing red oak mast abundance. Over a large spatial (30 counties) and temporal (22 years) scale we examined fawn recruitment by predicting lactation status of female harvested white-tailed deer in the Appalachians Mountains of western Virginia. We found land cover diversity index positively and black bear (<i> Ursus americanus </i>) detection rate negatively influenced recruitment. Age also predicted lactation status with middle-aged females (3.5–4.5 years old) having a higher lactation probability than mature (≥5.5 years old) age and young (2.5 years old) age class deer. Based on these findings, recruitment is likely to be greater in areas that have a mixture of land cover types. Therefore, if an increase in recruitment is desired silvicultural practices such as fire and timber harvest could be used to permanently change land cover types. These silvicultural practices could also be used to increase the number of oaks on the landscape, and augment production of mature oaks as red oak mast abundance influenced fawn survival. Also reducing predation by manipulating predator densities could improve recruitment. Overall, we found diversity of land cover types, food availability, predators, and age influences population dynamics of white-tailed deer.

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