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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.
51

Integrating Black Bear Behavior, Spatial Ecology, and Population Dynamics in a Human-Dominated Landscape: Implications for Management

Raithel, Jarod D. 01 August 2017 (has links)
The New Jersey Division of Fish and Wildlife (NJDFW), in collaboration with Bear Trust International, presented us an opportunity to examine a long-term (33 years) American black bear (Ursus americanus) data set from northwestern New Jersey (NJ), USA. State agencies continue to grapple with uncertainty about the efficacy of socially divisive management actions such as recreational harvest and lethal control as tools to reduce escalating human-bear conflicts. We applied multistate capture-reencounter models to a large sample of black bear captures (>5,000) and dead recoveries (>1,300) between 1981 – 2014 to estimate cause-specific mortality and spatial dynamics between wildland and anthropogenic habitats. Additionally, we assessed temporal correlations between more than 26,500 reported human–black bear interactions and mortality rates. Adult females were twice as likely (0.163 ± 0.014) as males (0.087 ± 0.012) to be harvested, and cubs (0.444 ± 0.025) and yearlings (0.372 ± 0.022) had a high probability of dying, primarily from vehicle strikes. Nuisance behaviors reported declined with increasing harvest and lethal management (P = 0.028, R2 = 0.338). Adult bears previously designated as a nuisance and/or threat (hereafter, “problem”) were more likely to be harvested (0.176 ± 0.025) than those with no conflict history (0.109 ± 0.010). Combined legal kills and vehicle strikes, the two greatest mortality causes for marked bears, occurred significantly less than expected per unit area in urban and agricultural areas, and more than expected in the wildland-urban interface and wildland habitats. Across all age-classes, problem bears were significantly more likely to transition to anthropogenic habitats, yet they died at lower rates than conspecifics with no history of conflict in wildlands. Cubs and yearlings died at significantly higher rates than adults in the risky interface habitat, corroborating independent estimates of their increased susceptibility to harvest and vehicle strikes. Ultimately, wildland habitats represented a population source (λ = 1.133) and anthropogenic habitats a sink (λ = 0.945). Harvest represents an important management tool to help meet population targets and decrease human-bear conflicts by disproportionately removing problem bears.
52

POPULATION ABUNDANCE AND GENETIC STRUCTURE OF BLACK BEARS IN COASTAL SOUTH CAROLINA

Drewry, John Michael 01 August 2010 (has links)
Because of increasing frequency of bear sightings, vehicle collisions, and nuisance incidents in coastal South Carolina, the South Carolina Department of Natural Resources is developing a comprehensive black bear management plan. However, no reliable estimates of population abundance or density are available. I used genotypes of black bears determined from hair samples collected in Lewis Ocean Bay and Carvers Bay to estimate population abundance and density. I obtained hair samples from snares during 8 weekly sampling periods in 2008 and 2009. I used Huggins closed population models to estimate abundance and spatially explicit capture- recapture models to estimate density. Based on model averaging, black bear abundance was 30 (SE = 9.3) on Carvers Bay and 42 (SE = 5.4) on Lewis Ocean Bay. Model-averaged density was 0.037 bears/km2 (SE = 0.003) for Carvers Bay. For Lewis Ocean Bay, population densities were much higher: 0.307 bears/km2 (SE = 0.025). I extrapolated the density estimates to the upper coastal region of South Carolina, using logistic regression to weight density based on similarity of the regional landscape with the 2 study areas. Predicted bear densities were low throughout the coastal region but several areas centered on more productive habitats (e.g., Carolina Bays, pocosin) and public lands (e.g., Francis Marion National Forest, Lewis Ocean Bay) had high densities. I also sampled an area in North Carolina and assessed genetic structure among the 3 areas. Based on heterozygosity, genetic distance, and genetic assignment, I found no evidence of historic or recent barriers to gene exchange among the 3 sampled populations. However, demographic connectivity may be a concern for areas such as Lewis Ocean Bay, which is surrounded by highways and development. If the goal is to maintain current black bear densities in those areas, maintaining connectivity with other habitat areas and mitigating impacts of highways would be important. The regional map of potential black bear density may be useful to identify areas that should be surveyed for occupancy or where additional studies may be conducted (e.g., Francis Marion National Forest).
53

Estimating population parameters of the Louisiana black bear in the Upper Atchafalaya River Basin

Lowe, Carrie Lynne 01 May 2011 (has links)
In 1992, the Louisiana black bear (Ursus americanus luteolus) was granted threatened status under the Endangered Species Act primarily because of extensive habitat loss and fragmentation. Currently, the Louisiana black bear is restricted to 3 relatively small, disjunct breeding subpopulations located in the Tensas River Basin of northeast Louisiana, the upper Atchafalaya River Basin (ARB) of south-central Louisiana, and coastal Louisiana. The 1995 Recovery Plan mandates research to determine the viability of the remaining subpopulations. I conducted a capture-mark-recapture study during 2007–2009 to estimate population parameters for the ARB bear subpopulation by collecting hair samples (n = 2,977) from 115 barbed-wire hair traps during 8 1-week periods each summer. DNA was extracted from those hair samples and microsatellite genotypes were used to identify individuals. I analyzed encounter histories using the Huggins full heterogeneity estimator in a robust design framework in Program MARK. I compared candidate models incorporating heterogeneity, behavior, and time effects on capture using information-theoretic methods. I directly estimated apparent survival, temporary emigration, probability of capture and recapture, and probability of belonging to 1 of 2 mixtures; population abundance was a derived parameter. Apparent survival was 0.91 (SE = 0.06) and did not vary by gender or year. There was some evidence of temporary emigration for males only (0.10, 95% CI = 0.001–0.900). I modeled capture probabilities with a 2-mixture distribution for both male and females. Overall mean weekly capture probability was 0.12 (SE = 0.03) and 0.25 (SE = 0.04) for males and females, respectively. Recapture rates indicated a positive behavioral response to capture. Model-averaged mean annual abundance was 56 (SE = 4.5, 95% CI = 49–68). I calculated population density using spatially-explicit maximum-likelihood methods; model-averaged density was 0.15 bears/km2 (SE = 0.03). My results updated previous abundance estimates for the ARB bear subpopulation and will be used in a population viability analysis to determine if recovery criteria for the Louisiana black bear have been met.
54

POPULATION ABUNDANCE AND GENETIC STRUCTURE OF BLACK BEARS IN COASTAL SOUTH CAROLINA

Drewry, John Michael 01 August 2010 (has links)
Because of increasing frequency of bear sightings, vehicle collisions, and nuisance incidents in coastal South Carolina, the South Carolina Department of Natural Resources is developing a comprehensive black bear management plan. However, no reliable estimates of population abundance or density are available. I used genotypes of black bears determined from hair samples collected in Lewis Ocean Bay and Carvers Bay to estimate population abundance and density. I obtained hair samples from snares during 8 weekly sampling periods in 2008 and 2009. I used Huggins closed population models to estimate abundance and spatially explicit capture- recapture models to estimate density. Based on model averaging, black bear abundance was 30 (SE = 9.3) on Carvers Bay and 42 (SE = 5.4) on Lewis Ocean Bay. Model-averaged density was 0.037 bears/km2 (SE = 0.003) for Carvers Bay. For Lewis Ocean Bay, population densities were much higher: 0.307 bears/km2 (SE = 0.025). I extrapolated the density estimates to the upper coastal region of South Carolina, using logistic regression to weight density based on similarity of the regional landscape with the 2 study areas. Predicted bear densities were low throughout the coastal region but several areas centered on more productive habitats (e.g., Carolina Bays, pocosin) and public lands (e.g., Francis Marion National Forest, Lewis Ocean Bay) had high densities. I also sampled an area in North Carolina and assessed genetic structure among the 3 areas. Based on heterozygosity, genetic distance, and genetic assignment, I found no evidence of historic or recent barriers to gene exchange among the 3 sampled populations. However, demographic connectivity may be a concern for areas such as Lewis Ocean Bay, which is surrounded by highways and development. If the goal is to maintain current black bear densities in those areas, maintaining connectivity with other habitat areas and mitigating impacts of highways would be important. The regional map of potential black bear density may be useful to identify areas that should be surveyed for occupancy or where additional studies may be conducted (e.g., Francis Marion National Forest).
55

Protecting biodiversity through monitoring of management indicator species questioning designations of Ursus americanus (black bear) and Plethodon jordani (Jordan's salamander) /

Sevin, Jennifer Ann, January 2003 (has links) (PDF)
Thesis (M.S.)--North Carolina State University, 2003. / Title from PDF title page (viewed on Jan. 13, 2005). Includes vita. Includes bibliographical references (p. 76-86).
56

THE RETURN OF THE BLACK BEAR TO EASTERN KENTUCKY: CONFLICT AND TOLERANCE BETWEEN PEOPLE AND WILDLIFE

Harris, Hannah B. 01 January 2011 (has links)
The black bear (Ursus americanus) has returned to Kentucky and is now part of a reproducing population in the southeastern Cumberland Mountain region. The broad objective of this project was to examine the interactions between people and bears, with the ultimate goal of improving bear management in a way that addresses stakeholder concerns. Using interviews of regional stakeholders, participant observation, and media reports collected between summer 2003 and fall 2006, I investigated how the presence of black bears in Harlan and Letcher counties in Kentucky has had an impact on area residents. I complemented this information with observations of bear behavior and an analysis of bear capture and handling data collected within the study period. Artificial provisioning of bears was widespread and >60% of black bears captured were confirmed to use anthropogenic foods at least some of the time. I found a significant difference (P<0.0001) in the apparent physical condition of confirmed anthropogenic feeding bears and bears whose feeding behavior was unknown, and similar differences in physical condition between bears captured along traplines in Harlan and Letcher counties when compared to bears captured along traplines in Bell County (P<0.01). Mean litter size was 3.25 ± 0.11 (SE), significantly above average for eastern North America (P<0.05) although cub survival remains unknown. All documented mortality of adult bears was human-caused. Anthropogenic food sources may affect bear behavior, survival, reproduction, and physiology, as well as bring bears into close contact with humans. Artificial provisioning is currently an important part of bear-human interaction in eastern Kentucky, both facilitating bear tourism as well as precipitating nuisance problems. Cessation of provisioning could have important consequences for the developing tourism industry in the region and for the bears themselves. Both the Kentucky Department of Fish and Wildlife Resources and many local people have an interest in conserving bears, but problems have arisen due to differing conceptions of appropriate or desirable management. A better understanding of the human dynamics and cooperation taking place in this situation could provide much-needed information both in Kentucky and in other localities where stakeholders are debating how to co-exist with wildlife.
57

The bear as barometer: the Japanese response to human-bear conflict

Knight, Catherine Heather January 2007 (has links)
The Asiatic black bear, or 'moon bear', has inhabited Japan since pre-historic times, and is the largest animal to have roamed Honshu, Shikoku and Kyushu since mega-fauna became extinct on the Japanese archipelago after the last glacial period. Despite this, the bear features only rarely in the folklore, literature and arts of Japan's mainstream culture. This relative cultural invisibility in the lowland agrarian-based culture of Japan contrasts markedly with its cultural significance in many upland regions where subsistence lifestyles based on hunting, gathering and beliefs centred on the mountain deity (yama no kami) have persisted until recently. However, in recent decades the bear has been propelled from its position of relative cultural obscurity into the forefront of mainstream society's attention. As more and more of the bear's habitat is destroyed or degraded through forestry and development, the bear is increasingly encroaching onto human territory in its search for food, leading to pestilence and bear attacks. This thesis examines the nature of the contemporary human-bear relationship in Japan, dominated by human-bear conflict, or the so-called 'bear problem'. To better understand the contemporary response to the bear, the thesis explores the historical relationship of the Japanese with both the bear and its habitat, the forested uplands. The thesis further seeks to understand how cultural, historical, social and geographic factors influence a society's response to wildlife conflict and what can be learnt from the Japanese example which can be applied to the understanding of human society's response to wildlife conflict elsewhere.
58

HOME RANGE, HABITAT USE, AND FOOD HABITS OF THE BLACK BEAR IN SOUTH-CENTRAL FLORIDA

Ulrey, Wade Allen 01 January 2008 (has links)
I studied a small, enigmatic, and imperiled black bear population in south-central Florida from 2004 - 2006. Annual home ranges of males (96.0 km2) were larger than those of females (32.2 km2). Female home ranges were smaller in winter than in summer or fall. At the landscape scale, bears selected forests, scrub, and citrus, but avoided urban areas. At the home range scale, bears selected bay swamp and hardwood hammock, but avoided urban areas and grassland. Bears selected bay swamp in winter, forests and scrub in summer, and forests, scrub, and marsh in fall. The bear’s diverse diet included citrus fruit. Important foods were acorn, saw palmetto fruit, and Florida carpenter ant. The local landscape is dominated by agriculture on private lands, as opposed to large contiguous forests on public land elsewhere in Florida black bear range. Mean patch size of forests was smaller, while edge density, diversity, and evenness were higher in south-central Florida than elsewhere in the state. Diversity of forest habitat may partially account for the persistence of the black bear in this fragmented landscape. Managers should encourage private landowners to adopt practices that promote bear habitat, and focus on habitat diversity, road crossings, and statewide metapopulation structure.
59

FLORIDA PANTHER AND BLACK BEAR: A ROAD AND URBAN AVOIDANCE/UTILIZATION ANALYSIS AND IMPACTS OF LAND USE AND CLIMATE CHANGE ON LARGE CARNIVORE HABITAT IN FLORIDA

Whittle, Andrew James 01 January 2009 (has links)
Florida is expanding its urban borders into areas of the native habitat. Increased expansion is predicted through the next several decades. Several sections of the state are home to large carnivores, such as Florida panther and black bear, which are important to ecosystem function. Expansion of roads and urban centers will greatly reduce the quality and quantity of carnivore habitat. In this study, I used Euclidean distance analyses and very high frequency (VHF) telemetry points to produce distance categories in which carnivores either have a negative/neutral/positive association with roads and urban centers. The seven black bear populations followed four different trends: 1) Slight avoidance of roads and urban centers, 2) strong avoidance of roads and urban centers, 3) neutrality toward roads and urban centers, and 3) one population with a positive association of roads. Florida panther showed strong avoidance to roads and urban centers. Finally I modeled Florida panther and black bear habitat using Maximum Entropy Species Distribution software and placed future urban expansion and sea level incursions associated with climate change over the habitat to find high priority conservation areas.
60

Application of a Bayesian belief network to model black bear intertidal habitat quality

Howes, Jason 15 November 2010 (has links)
In this study, I document the steps taken to develop and apply a Bayesian belief network (BBN) model for identifying the probable black bear intertidal habitat quality of Clayoquot Sound, British Columbia. Initial model outputs provide a narrow range of probability values, resulting in three high quality intertidal habitat classes applied to the study area. Day-time, summer observations of bear intertidal utilization improve previous knowledge of bear behaviour and highlight preferred resources and habitat characteristics, along coastal margins. Black bear encounter rates are calculated for the individual and some combinations of the key environmental variables used within the model. Bear encounter rates increase with higher probability class. A revised BBN model is implemented through systematic methods applied to the comparison of the initial model conditional probability tables and black bear encounter rates. This final model improves the discrimination of intertidal habitats resulting in four classes. The range of probability values increases as do the encounter rates with successive higher probability classes. Future recommendations for improvements are presented.

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