There is a need to understand how free-ranging animals respond and adapt to stress. However, little is currently known regarding the physiologic adaptations to stress in bears, and there are few tools available to wildlife managers to assess the health and stress status of free-ranging animals, including ursids. The hypothalamus-pituitary-adrenal (HPA) axis plays major roles in the physiological adaptation to stress, leading to the increased secretion of glucocorticoids (e.g. cortisol in most mammals) that mediate adaptive changes in physiology and behaviour. The vast majority of glucocorticoids are bound to its primary carrier protein, corticosteroid-binding globulin (CBG), in most animals, and only the unbound fraction is bioavailable. Thus, CBG plays a major role in modulating glucocorticoid dynamics, and this protein must be characterized to build a more complete understanding of the adaptive role that the HPA axis plays in mitigating stress in bears. The overall objective of this thesis was to characterize the HPA axis activity and CBG levels in bears, and develop tools targeted towards the monitoring of the health and stress status of American black bear (Ursus americanus), grizzly bear (U. arctos), and polar bear (U. maritimus). The binding characteristics of cortisol to CBG in bears were studied via saturation binding experiments, and this information was used to estimate free cortisol concentrations based on CBG concentrations. To quantify CBG concentrations in bears, an enzyme-linked immunosorbent assay (ELISA) was developed. Grizzly bear CBG cDNA was cloned and sequenced, and an antibody was developed against a peptide sequence of the deduced amino acid sequence. The antibody showed good cross-reactivity against black, grizzly, and polar bear CBG, and the ELISA based on this antibody found differences in the mean CBG levels between species. Using this data, free cortisol levels were estimated, and mean levels were elevated in polar bears relative to black and grizzly bears. Having developed these tools, the roles that corticosteroid-binding globulin (CBG) and bioavailable cortisol played in the physiological adaptation to major life history traits and environmental challenges faced by ursids were investigated. Importantly, CBG was not modulated by the acute stress of capture and handling, despite the large differences in the magnitude of acute cortisol responses that are induced by these methods, suggesting that CBG levels may reflect the chronic health and stress status of bears. Altogether, there were few changes in CBG levels throughout much of the annual life cycle of bears, implying that CBG does not play a major adaptive role in the life history traits of bears and, instead, metabolic and environmental factors may be the key modulators of cortisol dynamics. However, CBG was not significantly associated with our measures of dietary patterns and nutrition, including body condition, seasonal dietary patterns, and fasting. The majority of the observed variation in the levels of this protein in bears remains unexplained. However, stress-induced free cortisol levels were negatively associated with urea to creatinine ratio (an indicator of dietary protein content and fasting status in grizzly and polar bears, respectively) and positively associated with lactation in hibernating black bears, suggesting that the variation in adrenal function may be playing an important role in the adaptation to adverse environmental conditions and/or metabolic stress in bears. In addition to serum cortisol dynamics, other proteins were also hypothesized to play adaptive roles in maintaining the hibernating phenotype in bears. Changes in the serum proteome during hibernation in black bears were assessed as a means to discover novel proteins that may be indicative of metabolic stress in bears. The serum proteomes of active and hibernating black bears were compared and analyzed for significant changes by two-dimensional electrophoresis and tandem mass spectrometry. Proteins involved with immune-related function were significantly altered during hibernation, leading to the proposal that the serum protein changes are essential for maintaining immune competence, wound healing, and bone structure. Altogether, this thesis developed a method to quantify CBG and estimated free cortisol concentrations in bears, and characterized their roles in the physiological adaptations associated with the major life history traits and environmental challenges faced by ursids. Also, novel serum proteins were identified as potential markers of immune function and health status in bears. These tools may be tremendously useful for wildlife managers and conservationists in determining how chronic stressors, including anthropogenic activities and climate change, may impact the stress and health performances of individual and populations of free-ranging bears.

Thesis (MFA)--Montana State University--Bozeman, 2009. / Typescript. Chairperson, Graduate Committee: Ronald Tobias. The Great Delta Bear Affair is a DVD accompanying the thesis. Includes bibliographical references (leaves 34-35).

Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1997. / Vita. Includes bibliographical references (p. 99-105).

abstract: In 1915, a bear slew and consumed seven residents of a farming hamlet in Hokkaido, Japan. The circumstances surrounding these killings are laden with semiotic gravitas. A comprehensive analysis of the millennia of historical forces that preceded and begat Japan's modern shift is impractical. Rather it is through the identification of the ideal précis of change, and a Thick Analysis thereof, that I arrive at an understanding of how, and precisely when, Japan crossed modernity's rampart. The attacks perpetrated by, and the hunt and dispatch of, the bear include aspects of separation from the past vis a vis their relationship to religion, the Ainu, and the artifacts of daily life. The bear's presence and anthropophagous propensity relate to the primal human urge to practice arctolatry, and Japanese patterns of relationship between men, land, and animals. So too is the gory nature of the incident analytically valuable insofar as macabre events resonate in the breasts of men. Finally, the presence of a monster indicates, as per Jeffrey Jerome Cohen, an epochal liminality. Thus through a disarticulation of this incident, I arrive at a cogent understanding of what sundered Japan from her past. / Dissertation/Thesis / Masters Thesis History 2020

North American black bears (U. americanus) and brown bears (U. arctos) can be difficult to distinguish in the fossil record due to similar dental and skeletal morphologies. Challenges identifying ursid material from Oregon Caves National Monument (ORCA) called for an accurate tool to distinguish the species. Ursid teeth have a high degree of variability and morphological features are not always diagnostic. This study utilized a large database of lower tooth lengths (p4, m1, m2, and m3) and ratios (p4/m1, m2/m1, m3/m1, p4/m3, m2/m3) in an attempt to differentiate U. americanus and U. arctos in North America. Further, this project examined how these linear measurements differ in response to ecoregion, latitude, and climate. Analysis of variance (ANOVA) found significant differences between U. americanus and U. arctos from across North America for every variable studied. Stepwise discriminant analyses (DA) found lengths separated species better than ratios with 99.1% correct classification versus 77.5% correct classification for ratios. When sexes were analyzed, ANOVA only found significant differences for lengths while DA found lengths and ratios could not accurately distinguish between sexes; only 72.1% of sexes were classified correctly while utilizing lengths and 61% for ratios. Seventeen previously identified fossil specimens from across North America, in addition to the ORCA specimen, demonstrated the utility of this study, confirming several identifications and rejecting others, proposing the need for new designations.

The Central American Isthmus has had profound effects on the evolution and distribution of larger marine organisms, but the impacts on meiobenthic animals have received little attention. Tardigrades are microscopic metazoan lobopodians that are ubiquitous in benthic communities worldwide, but little is known about marine tardigrades in Central America. Only two marine tardigrades have been identified to species level in all of Central America, and these came from a single sample of barnacles from El Salvador collected in 1953. Additionally, multiple haplotypes of Echiniscoides were reported from Costa Rica and Panama, but species names were not assigned. Here we report an extensive survey of both intertidal and subtidal marine tardigrades from both the Caribbean and Pacific coasts of Costa Rica. We found 701 individuals in 65 samples. There was a total of 19 taxa, including seven species with a sufficient quality and quantity of specimens to describe here as new to science. The new species are Archechiniscus murilloi sp. nov., Batillipes homocercus sp. nov., Batillipes ichthyocercus sp. nov., Echiniscoides costaricensis sp. nov., Echiniscoides ritavargasae sp. nov., Styraconyx vargasi sp. nov. and Tanarctus breedyae sp. nov. Ten taxa were found only in the Caribbean, six were found only in the Pacific, and three were found on both coasts. We discuss the three species with trans-isthmus distributions and note two additional candidate geminate species pairs that warrant further investigation.

Effort and success of Virginia's bear houndsmen were determined through field and mail surveys, and hunter diaries. The number of houndsmen per chase ranged from 5 to 12, hounds ranged from 6 to 11, and each chase lasted 2 to 6 hours. Second chases of the day lasted 2 to 3 hours and 3 to 10 hounds were used. Fifty-three to 74% of all first attempts resulted in a chase and 24% to 44% of these bears treed. A 2nd chase occurred in 11% to 96% of attempts and 9% to 50% of bears treed. Five to 17% of the 1st bears and 13% to 21% of 2nd bears were harvested. Field surveys found virtually no differences in hunting effort or success between seasons, study areas, and years. The hunter diary appears to be the most reliable means of sampling hunter effort and success. The applicability of Schroeder's physical condition estimate (PCR) was tested on data from Maine's black bear population. Bears exposed to poor hard mast had lower PCR's than bears exposed to good hard mast (P = 0.009). PCR and body weights of adult female black bears in Virginia exposed to hunting did not differ from those not hunted (P = 0.09). Annual adult female, adult male, and cub survival and reproductive rates in the hunted population were numerically similar to those in the non hunted populations. Five radio collared females were experimentally chased by hounds. The chases,on average, lasted 0.9 hours and 43% of bears treed. The average total home range for 3 of the bears was 17.8 km². The area used by 2 of the 3 bears pursued by hounds did not differ from their total home range (P 3 0.05) based on the MRPP test. The area covered by 3 of the 5 pursued bears was 5.6%, 11.8%, and 79.7% of their home range. / Master of Science

What kind of animal was a black bear? Were black bears primarily pests, pets, furbearers or game animals? Farmers, conservationists, tourists, trappers, and hunters in early twentieth-century Ontario could not agree. Even as the century progressed, ideas about bears remained twisted and there was often very little consensus about what the animal represented. These varying perceptions complicated the efforts of the provincial Department of Game and Fisheries and its successor agencies, the Department of Lands and Forests and the Ministry of Natural Resources, to develop coherent bear management policies. Perceptions about black bears often conflicted and competed with one another and at no one time did they have a single meaning in Ontario. The image of Ontario’s black bears has been continuously negotiated as human values, attitudes, and policies have changed over time. As a result, because of various and often competing perspectives, the province’s bear management program, for most of the twentieth century, was very loose and haphazard because the animal had never been uniformly defined or valued. Examining the history of these ambiguous viewpoints towards the black bear in Ontario provides us with a snapshot of how culture intersects with our natural resources and may pose challenges for management. / Dissertation / Doctor of Philosophy (PhD)

We measured black bear (Ursus americanus) reproduction and cub survival during 1994 - 1998, and 1995 - 1999, respectively, in the George Washington and Jefferson National Forests in Virginia to determine age-specific and overall cub production and cub survival. We observed females in estrus between 6 June and 22 August; the mean date of estrus was 17 July. Ages of primiparity ranged between 3 and 5 years with an average of 3.36 years (n=11, SE=0.15). Average litter size for 1995 - 1998 was 2.32 cubs/litter (SE=0.11, n=53) and 85.7% of available females ≥ age 4 (those not accompanied by cubs) reproduced in a given den season. We monitored 98 (48M:50F) black bear cubs equipped with expandable radio-collars (Higgins 1997) or radio transmitters implanted subcutaneously between 1995 and 1999 to estimate cub survival. Kaplan-Meier staggered entry analysis provided 306-day survival rates for 82 cubs. The survival estimates for males and females were 73% (0.49, 0.96) and 91% (0.80, 1.00), respectively. The overall 306-day survival rate for all cubs was 81% (0.67,0.94) using Kaplan-Meier and 76% (0.63, 0.92) using Heisey-Fuller (Mayfield) methods. We also evaluated the utility of radio transmitters implanted subcutaneously in 42 (21M:21F) wild black bear (Ursus americanus) cubs from 2 study areas in Virginia between 1996 and 1999 to monitor first year cub survival. More than 64% (27 of 42) of the implants fell out prematurely (2-198 days), and 16.6% (7 of 42) failed for unknown reasons. Less than 5% (2 of 42) of these cubs denned wearing failed implants, and 9.5% (4 of 42) experienced mortality less than 1 month after implant surgery. About 9.5% (4 of 42) of implanted black bear cubs wore working transmitters through to the following den season. / Master of Science

Human-bear interactions are an important consideration of bear biology, as interactions can lead to destruction of property as well as injury or death for both human and bear. Successful analysis of why these interactions occur can lead to appropriate preventative measures and mitigation of further conflict. Bryce Canyon National Park (BRCA) is comprised of relatively poor bear habitat, but a black bear population exists on the Paunsaugunt Plateau, on which the park occupies the eastern edge. Park managers expressed interest in learning more about bear movements and, specifically, bear use of anthropogenic features following a number of human-bear incidents located at backcountry campsites within park boundaries. By analyzing data from GPS radio-collared bears, trail cameras, existing literature, park incident reports and in-depth campsite assessments, we were able to show how bears are using both natural and anthropogenic features on the Bryce landscape. Campsites were assessed for bear habitat, displacement and encounter potential in order to establish an overall human-bear conflict potential. AIC model selection and resource selection functions using GPS collar data showed that bears selected for some anthropogenic features (campsites, springs), while actively avoiding others (trails, roads). Trail camera data, existing literature and park incident reports all pointed toward use of trails. We then considered all data sources used in the analysis and compiled rankings of human-bear conflict potential for each of the backcountry campsites within BRCA, and submitted a detailed report of findings, conclusions and recommendations to NPS personnel. Second, we investigated human-bear interactions at polar bear dens sites on Alaska's North Slope. As parturient female polar bears in the Southern Beaufort Sea subpopulation increasingly construct maternal dens on coastal land features rather than sea ice, they become more likely to interact with industry and other human activity. We wanted to understand what levels of human interaction could lead to disturbance of denning polar bears, and what types of responses were being exhibited by bears following those interactions. We subdivided potential disturbance stimuli into groups based on their size, motion and sound and the used AIC model selection techniques and multinomial logistic regression to analyze records of human-bear interactions at den sites ranging from 1975 through the present day. We found significant probabilities of varying levels of bear disturbance response among a number of stimuli and intensities. However, denning bear families were overall more tolerant of human activity near den sites than expected. Den abandonments were rare, and we documented no cases of reproductive failure following a disturbance event. We hope that our results from the analysis can be used to further enhance management of industry when operating in polar bear denning habitat.