Download or read book Using Stable Isotopes to Assess Longitudinal Diet Patterns of Black Bears Ursus Americanus in Great Smoky Mountains National Park written by Jennapher L. Teunissen van Manen and published by . This book was released on 2011 with total page 96 pages. Available in PDF, EPUB and Kindle. Book excerpt: Long-term diet patterns based on stable isotope analysis may be helpful to understand changes in food selection of black bears (Ursus americanus) over time and guide management programs to reduce human-bear conflicts. An enriched stable carbon isotope signature indicates an anthropogenic food source in the diet and an enriched nitrogen signature indicates a higher tropic level for a species. I examined longitudinal feeding patterns from 117 hair samples of black bears live captured in Great Smoky Mountains National Park during 1980-2001 using stable carbon and nitrogen isotope analysis from hair samples. I developed a set of a priori models to examine if sex, age class, year, weight class, total hard mast index, white oak index (Quercus spp.), red oak index (Quercus spp.), nuisance status and hog harvest (Sus scrofa) affected stable isotope signatures. I used model averaging and an estimator of the unconditional variance was used to account for model uncertainty. The [delta]13C signatures differed by weight class with above average weight, ([Beta] = 0.76[Per-mille]; 95% CI = 0.28 to 1.23) and average weight ([Beta] = 0.42[per-mille]; CI = 0.06 to 0.78) showing enriched values compared to below average bears. Bears had enriched [delta]15N signatures in years with low white oak mast production ([beta] = -0.19, CI = -0.34 to -0.03) and depleted when white oak hard mast was abundant. Sub adult bears had enriched [delta]15N signatures compared to adult and older adult bears. Variation of nitrogen values was small during 1980-1991(x̄ =2.57, SD = 0.28) but increased substantially during 1992-2000 (x̄ = 2.29, SD = 0.71) when there was substantial variation in hard mast production. Bears in better physical condition appear more likely to access anthropogenic food sources. In years of low white oak acorn production, the larger bears and sub adult bears are more likely to turn to alternative food sources. The long term variation detected in this study is important in identifying which bears are potentially more likely to seek out the anthropogenic food sources when changes occur in availability of natural foods.

Download or read book Using Stable Isotope Analysis to Estimate Black Bear Ursus Americanus Diet in Vermont written by Eliese Antona Dykstra and published by . This book was released on 2015 with total page 274 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Use of Stable Isotope Ratio Analysis to Characterize the Diets of American Black Bears in Great Smoky Mountains National Park and Utah written by Amanda Kathleen Loveless and published by . This book was released on 2007 with total page 60 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Use of Stable Isotopes to Investigate Black Bear Diets and to Evaluate the Human bear Management Program at Yosemite National Park CA written by John Brooks Hopkins (III.) and published by . This book was released on 2011 with total page 338 pages. Available in PDF, EPUB and Kindle. Book excerpt: Yosemite has applied extraordinary effort to manage people and bears over the past century. For the past decade, human-bear management has implemented both proactive (population-level) and reactive (individual-level) management to prevent bear incidents; however, incidents continue to occur at high frequency even though the program has received $500,000 in congressional funding each year since 1999. For this study, we developed a new method to detect human food-conditioned (FC) bears throughout the Park using isotopic data and used these results and dietary estimates for these bears to evaluate the effectiveness of the human-bear management program. In the first chapter, we proposed 40 definitions for terms and concepts common to human-bear management. In the second chapter, we provide details on a stable isotope mixing model designed to accurately estimate dietary parameters in the remaining two chapters. In these last chapters, we collected tissues (bone and hair) from contemporary and historic bears with known and unknown management statuses (FC or non-food-conditioned [NFC]) and analyzed them for their stable isotopic composition. In chapter 3, we used these isotopic data to predict the management status of unknown bears using a logistic regression model. For chapters 3 and 4, we used isotopic data for FC bears and stoichiometric data for their food sources to estimate the proportional dietary contributions to bear diets through time using our mixing model. Results from chapter 3 show a small proportion (~13%) of the unknown sampled population (n = 145) is currently FC, and chapter 4 results showed the proportion of human food in food-conditioned bear diets increased before the park began implementing a rigorous proactive human-bear management strategy in 1999. Since then, the amount of human food in known FC bear diets has decreased dramatically. We conclude that proactive human-bear management was effective at reducing the amount of human food available to bears since 1999. In contrast, evidence suggests reactive human-bear management was not effective at eliminating or reducing the amount of human food in individual bear diets. We suggest the Park reevaluate the effectiveness of their reactive human-bear management strategy, reduce problem bears from the population, and continue proactive management.

Download or read book Paleozoological Stable Isotope Data for Modern Management of Historically Extirpated Missouri Black Bears Ursus Americanus written by Corinne N. Rosania and published by . This book was released on 2010 with total page 65 pages. Available in PDF, EPUB and Kindle. Book excerpt: Human population growth and intensification of resource extraction during the 19th century changed the American landscape. Deforestation, residential sprawl and hunting activities impacted the behavior and sometimes the existence of native species. By the early 1900s, North American black bears (Ursus americanus) were extirpated from Missouri. Modern efforts to restore this species to the region are guided by the assumption that extant extra-local black bear ecology accurately depicts native Missouri ursid ecology. Paleozoological data provide the only means to test this assumption. Stable carbon and nitrogen isotope analysis of skeletal remains of ten late Holocene black bears from Lawson Cave in central Missouri reveals three aspects of native black bear diet: 1) Lawson Cave black bears are isotopically distinct from herbivores and carnivores; 2) There is no clear trend in black bear diet over the past 600 years; and 3) Lawson Cave black bear diet is not significantly different from that of modern black bears. Native Missouri black bears, as reflected by the Lawson Cave ursids, are no different from extralocal modern black bears in terms of diet. Therefore, these ecological data can be applied to future management and conservation planning regarding Missouri black bears by indicating appropriate regions (which can support the resource-use habits of black bears) for relocation programs.

Download or read book Applications of Stable Isotope Analysis to Advancing the Understanding of Brown Bear Dietary Ecology written by Matthew C. Rogers and published by . This book was released on 2021 with total page 258 pages. Available in PDF, EPUB and Kindle. Book excerpt: Dietary ecology is one of the most important drivers of brown bear fitness at the individual and population levels. However, researchers do not have an in-depth understanding of the trophic niche breadth, diet composition, and seasonal diet variation for most Alaskan populations. I set out to better understand multiple facets of brown bear dietary ecology using stable isotope analysis (13C & 15N) as the primary tool to infer brown bear diet and gain insights into their trophic niche, dietary seasonality, dietary generalism and specialism, and isotopic trophic discrimination factors. I determined that using sectioned hair samples is the best practice for determining the isotopic trophic niche of brown bears. Additionally, I determined amino acid trophic discrimination factors for brown bears and explored the ability to separate salmon species in bear diets. I also used stable isotope mixing models with sectioned hair samples to infer seasonal dietary patterns of individual bears in five distinct Alaskan ecosystems. Approximately one-quarter of bears relied solely on vegetation over multiple years despite access to other sources of nutrition; these bears could be considered specialists. Other bears, approximately half, switched diets seasonally but had the same pattern of resource use year over year, a foraging class that I termed persistent seasonal generalism. Approximately one-quarter of bears did not have a persistent dietary pattern across years and could be considered true generalists. Most bears appear to have preferred dietary patterns that are persistent through time, which may be indicative of foraging inertia; maintaining foraging patterns even when faced with changing resource availability due to natural fluctuations, disturbance, or climate change. The sum of this work advances our understanding of brown bear dietary ecology from the individual seasonal level to population level degrees of generalism and specialism, and the methods developed can be applied to many species for which dietary ecology information is difficult to obtain.

Download or read book Caloric Production of Black Bear Foods in Great Smoky Mountains National Park written by Robert Michael Inman and published by . This book was released on 1997 with total page 326 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Radioisotope Feces Tagging as a Population Estimator of Black Bear Ursus Americanus Density in the Great Smoky Mountains National Park written by Daniel C. Eagar and published by . This book was released on 1977 with total page 89 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Foraging Ecology and Aging of Black Bears in Human modified Landscapes written by Rebecca Kirby and published by . This book was released on 2016 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: As human-modified landscapes now predominate globally, understanding the role of novel habitats in modifying animal behavior is increasingly important. Such new conditions can change animal foraging behavior, with important implications for individual condition, and biological aging. American black bears (Ursus americanus) are long-lived opportunistic omnivores that exhibit highly plastic foraging strategies, utilize seasonal hibernation, and are increasingly found in developing landscapes. As such, bears may alter their behavior to take advantage of differing availabilities of food subsidies, with important consequences at the individual- and population-level. My dissertation investigates the interactions of habitat and human activity on the foraging and aging ecology of black bears. Using stable isotopes to analyze diet, and telomeres as a molecular marker for biological aging, I examined bears at multiple scales in Colorado and Wisconsin. Each chapter of this dissertation is written (and formatted) as a manuscript for publication in a scholarly journal. Chapter 1 (published in Biological Conservation) investigated bear foraging throughout the Colorado landscape, and found that levels of human activity drove bear diet, and foraging on subsidies increased risk of conflict. Chapter 2 (in review at Evolutionary Ecology) explored the relative importance of such environmental factors and individual characteristics on biological aging in these Colorado black bears, and discovered a latitudinal pattern in telomere length that is likely driven by habitat differences. Chapter 3 (in review at Journal of Applied Ecology) characterized the high reliance of northern Wisconsin black bears on intentionally provisioned subsidies in the form of bear bait -- over 40% of their lifetime diet was derived from bait sources. Finally, Chapter 4 (prepared for submission to Functional Ecology) inspected a small population of longitudinally sampled black bears in southwestern Colorado to consider how foraging and hibernation influence stress and biological aging, and found that hibernation length slowed biological aging, but that foraging on subsidies could shorten hibernation. Overall, the work here demonstrates the remarkable habituation of black bears to food subsidies at multiple scales, and how accompanying changes in behavior and hibernation characteristics may have associated effects at the population and molecular levels, and suggests strategies for managing such populations.

Download or read book An Evaluation of Radioactive Feces tagging as a Technique for Determining Population Densities of the Black Bear Ursus Americanus in the Great Smoky Mountains National Park written by Larry Calvin Marcum and published by . This book was released on 1974 with total page 190 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Seasonal Changes in White Adipose Tissue in American Black Bears Ursus Americanus written by Elizabeth Marie Hill (Researcher in animal science) and published by . This book was released on 2013 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: American black bears have an intricate seasonal physiology, eating an entire year's worth of food in 7-9 months, and then losing that weight during hibernation with almost no activity. The black bear thus represents a novel model in which to study seasonal regulation of food intake and metabolism. What controls the seasonal changes in fat deposition and metabolism in bears is unknown. Adipokines, such as leptin, regulate food intake and metabolism, and we hypothesized that these adipokines vary seasonally in bear adipose tissue, in a manner that correlates with fat storage. The study population consisted of wild bears from the Great Smoky Mountains National Park (GSMNP) and New Jersey and captive bears from facilities in Tennessee and North Carolina. Blood and subcutaneous fat were collected from all bears, and abdominal fat and liver samples were collected from euthanized bears. Body length and weight were measured and converted into a modified body mass index score. Circulating levels of triglycerides, non-esterified fatty acids, beta-hydroxybutyrate, leptin, and adiponectin were measured to assess lipid and glucose metabolism. A radioimmunoassay was validated for use in bears to measure serum leptin concentrations. Quantitative PCR was used to measure mRNA expression of leptin, adiponectin, pyruvate dehydrogenase kinase isoenzyme 4 (PDK4), and protein kinase, AMP-activated, alpha 1 catalytic subunit (PRKAA1) in the fat samples collected across seasons. Adipocyte size was measured as an additional index of adiposity. There were significant variations in body mass due to sampling lean bears in the GSMNP as compared to obese captive bears. PRKAA1 and adiponectin expression in subcutaneous fat were significantly greater in captive fall bears as compared to captive summer and captive winter bears. Circulating levels of beta-hydroxybutyrate were significantly less in captive bears as compared to wild bears. Circulating levels of leptin and leptin expression in subcutaneous fat did not change by season. Circulating levels of adiponectin were significantly higher in the fall as compared to summer and winter. Analysis of fatty acids revealed that cis-vaccenic, palmitic acid and stearic acids were prevalent in the bear. Correlation analyses identified significant relationships among adipokines, expression of metabolic genes and lipid metabolites.

Download or read book Population Characteristics Movements and Activities of the Black Bear Ursus Americanus in the Great Smoky Mountains National Park written by Larry Eugene Beeman and published by . This book was released on 1975 with total page 218 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Spatial and Temporal Patterns of a Generalist Urban Carnivore American Black Bears Ursus Americanus at Lake Tahoe CA written by Mario Klip and published by . This book was released on 2018 with total page 149 pages. Available in PDF, EPUB and Kindle. Book excerpt: Human populations are growing and exert an increasing pressure on remaining wild habitats. Development and encroachment into wild habitats often create a wildland-urban interface. Understanding how and which species are able to persist or even flourish in these shared habitats, is important for conservation purposes and reducing human-wildlife conflict. Human-wildlife conflict may be of particular concern when it involves larger carnivores. Urban wildlife involved in conflict sometimes may be considered to have a lesser ecological value than its wild counterparts. This is particularly the case when animals are thought to be reliant on garbage and other human-provided food sources. However, as wild habitats shrink, wildlife cannot be exclusively preserved in remote wilderness settings. The American black bear (Ursus americanus) is a good example of an adaptable animal that is able to thrive in human-modified habitats but consequently is involved in high levels of reported bear-human conflict. Black bears are not endangered in most of their range, but lessons learned from this charismatic animal are likely applicable in deeper conservation contexts. In this dissertation, I attempted to better understand what it means to be classified as an urban animal, how spatial distributions and resource selection might vary between urban and wild areas, how drought might affect distributions, and how bear behavior might be influenced through human induced stimuli. First, despite its ubiquitous use, the term “urban” was not homogenous throughout the scientific literature and needed to be defined. Spatially defined urban extents have great influence on whether wildlife is deemed urban or not. This was even more important because the prevailing paradigm prior to this study was that black bears observed in urban areas were spending the majority of their time in this habitat. From 2010-2014, I outfitted 27 bears with GPS Iridium radio collars in Lake Tahoe to understand spatial usage. I assessed existing urban definitions and tried to define the most conservative definition that would include human development in the broadest sense. I assessed whether bears were spending 50% or more of their time in urban areas, if they did I considered them urban. During 2010-2011 no bears spent ≥50% of their time in urban areas; during 2012 25% of the bears spent ≥50% of their time in urban areas, whereas during 2013, 2014 and 2015 half of the bears spent ≥50% or more of their time in urban areas. Additionally, I assessed preference at three different orders (scales). While bears appeared to prefer urban habitats at first order (defined as the study area), they generally did not select urban habitats within their home range (second order). Further, I evaluated how home range estimates varied as a result of the method used and between urban and wild habitats. My results indicated that different home range tools and methods yielded different home range sizes and configurations. Home range sizes were not consistently statistically different from other published, mostly wild, bear home ranges. Additionally, I tried to illuminate how use of the urban area might increase as a result of drought. The Lake Tahoe region and California as a whole suffered a prolonged drought from 2012-2016. Wildlife were expected to seek out anthropogenic resources in close proximity to human habitation to overcome natural food deficits. An uptick in urban use in 2014 was noted and might be attributable to drought conditions. An effort was made to identify patterns in space use as a result of sex and season, and results indicated that home range sizes for females and females with cubs did not differ in size. Additionally, I assessed how models might provide different results between urban and wild areas. During the fall season, overlap with the urban portion of the home range was strongest, and use was even more pronounced during the fall of 2014 as a result of drought impacts. The RSF function included roads, roads with speeds greater than 35 mph, hiking trails, wetlands, known bear conflict areas and elevation. Females with cubs selected for areas of known conflict, which is supported anecdotally by the large number of bear-human conflicts reported by a small number of females with cubs. Finally, human-wildlife conflict has been growing globally and conflicts involving black bears also increased in number and significance throughout the western United States. This trend was particularly evident throughout the Lake Tahoe Basin. After meetings throughout the last decade with many local and regional stakeholders, including the late Senator Dave Cox, the California Department of Fish and Wildlife decided to implement aversive conditioning (AC) in addition to a continued education effort and depredation process allowing lethal removal of nuisance bears. AC was not intended to, nor had it previously been successful in persuading bears to leave urban areas. It had shown success, though, in modifying the behavior of certain bears by scorning bold behavior and rewarding their natural, shy behavior. I studied the effectiveness of using Karelian bear dogs and less-lethal ammunition to condition the behavior of bears. Three protocols were used: soft release, release with dogs, release with dogs and less-lethal ammo. I tested when bears would return to the capture location, reliance on the urban envelope, whether averted bears became more nocturnal, selected a hibernacula further away developed areas, were less winter active, decreased their foraging on anthropogenic resources and usage of known conflict areas. Contrary to expectation, some bears did not return to their capture or release locations. The majority of these individuals had experienced AC, with AC with Dogs appearing to have the greatest effect. Additionally, the return to patch time (BRP) for bears treated with Karelian bear dogs was greater than bears in the Control group for their return to both capture and release locations. Dogs also had the greatest effect on all behavioral proxies examined and bears treated with Dogs seemed to become more nocturnal, less winter active and spent less time in urban areas. These impacts of bear behavior may ultimately reduce the level of conflict with humans. The research presented in this dissertation adds to the growing body of literature on wildlife in the wildlife-urban interface and black bears specifically. Black bear behavioral responses to AC and how they may become less likely to engage in conflict showed promising results. My work suggested that a bear’s ecology living in the wildlife-urban interface may be more complicated and that mixed space use strategies, using both wild and urban areas, appear to be common.

Download or read book Patterns in Landscape wide Spatial Heterogeneity of American Black Bear Ursus Americanus Populations Identified Through Genetic and Noninvasive Approaches written by Catherine Sun and published by . This book was released on 2019 with total page 284 pages. Available in PDF, EPUB and Kindle. Book excerpt: Population-level patterns reflect the aggregation of individual-level movement, survival, and recruitment processes over a landscape. Estimating population density, distribution, and genetic structure is important for understanding species ecology, monitoring viability, and for developing effective management plans. Long-term monitoring is particularly necessary for detecting changes that have management implications. However, limited resources often impede the collection of sufficient high-resolution demographic data for robust population-level inferences, especially for species with extensive distributions and large ranges of individual movement. The American back bear (Ursus americanus) is a game species in New York (NY) that has been growing in abundance and expanding in distribution. However, robust knowledge of spatial variation in population density or genetic structure informative about current and future population trajectories is lacking. This research estimated patterns of landscape-wide spatial heterogeneity in NY bear populations using noninvasive, cost-efficient methods. First, I investigated the genetic structure of bears in NY and across the northeastern United States using neutral markers to reveal differentiation and patterns of restricted gene flow that may pre-date historical human disturbances. Genetic connectivity across political borders supports previous hypotheses of bear movement that motivate continued monitoring and coordination between management units. Second, I developed a citizen science (CS) program and conducted simulations with a novel integrated model to assess the utility of opportunistic CS data in augmenting systematic data to estimate population parameters. Then, I estimated bear density and patterns in bear density, distribution, and occupancy related to landcover types in southern NY with systematic spatial capture-recapture, occupancy, and CS approaches from 2015-2018. Across years, mean predicted density was 7.3 bears /100 km2 (95% CI: 4.7 - 11.5) with population growth, survival, fecundity, and landcover patterns suggesting that bears may continue to expand into areas with more human-impacted landscapes. Accounting for dependence between collocated sampling methods increased overall detection probability and highlighted the importance of appropriate spatial scales of different sampling methods for inference on population density. These findings provide the first spatially explicit, non-harvest based estimates of black bear population patterns across southern NY, and offer insights into the design of large scale, multi-method, long term population monitoring.

Download or read book Use of Stable Isotopes to Determine Diets of Living and Extinct Bears written by Grant Vaughan Hilderbrand and published by . This book was released on 1995 with total page 58 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Seasonal Food Habits of the Black Bear Ursus Americanus in the Smoky Mountains of Tennessee and North Carolina written by Larry Eugene Beeman and published by . This book was released on 1971 with total page 62 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Foods of Black Bears in the Great Smoky Mountains National Park written by Thomas C. Eagle and published by . This book was released on 1979 with total page 104 pages. Available in PDF, EPUB and Kindle. Book excerpt: