Large carnivores in the United States are making a comeback following decades of systematic eradication. Black bears (Ursus americanus), cougars (Puma concolor), and gray wolves (Canis lupus) may recolonize the midwestern United States provided there is substantial suitable habitat. However, viability of large carnivore populations is as dependent on social acceptance as on biological factors. I developed individual and combined models of suitable habitat for black bears, cougars, and wolves in 18 midwestern states using geospatial data, expert-opinion surveys, and multi-criteria evaluation. I also assessed attitudes and perceptions of Illinois citizens about large carnivores via a mail-in survey. Experts indicated land cover was the most important variable for predicting potential habitat for black bears and cougars; human density was the most influential variable for wolves. Large, contiguous areas of suitable habitat comprised 35%, 21%, and 13% of the study region for wolves, bears, and cougars, respectively. About 12% of the region was considered suitable for all 3 species. Arkansas, Minnesota, Texas, and Wisconsin had the highest proportions (>40%) of suitable habitat for black bears; Arkansas, Michigan, Missouri, Texas, and Wisconsin had the most (≥20%) suitable cougar habitat; and only 4 states in the study region contained <29% suitable wolf habitat. Models were validated by comparing suitability values of independent sets of known carnivore locations to those of random locations, and models appeared accurate. More than 70% of survey respondents (n = 791) were male and their average age was 60; 55% were hunters. Approximately 40% were unsure about the population status of large carnivores in Illinois; of the remaining respondents, most (ranging from 20% for black bears to 41% for cougars) believed the presence of all 3 species had increased over the past decade. More residents supported protection (43%) and increasing numbers of large carnivores (39%) than opposed them (26%), although support for black bears was slightly higher than for cougars and wolves. Rural residents and livestock owners were the most likely to want carnivore numbers to decrease and least likely to support their protection; higher levels of education corresponded to positive attitudes toward large carnivores. My research provides the foundation for well-informed management plans, policy decisions, and educational initiatives for large carnivores in midwestern states where large carnivore populations have been absent for decades.

Historically, black bears occurred throughout Mississippi but by 1932, <12 bears remained. Repatriation in neighboring states and conservation efforts in Mississippi have led to the recolonization of at least 2 subspecies (U. a. luteolus and U. a. americanus) of black bears in the state. I compiled available data to provide a synthesis of the history, current status, and management of black bears in Mississippi. Additionally, I used global positioning data collected from radio collared bears to determine the influence of distance to source population, cover type, distance to roads, distance to water, wetland reserve program areas, and human population density on black bear resource selection at various spatial scales. I studied characteristics of space use and resource selection of recolonizing bears in the Mississippi Alluvial Valley (Delta). I assessed the influence of environmental parameters at the female core annual home-range (using 50% kernel density estimator) and male and female seasonal and annual home-ranges (95% kernel density estimator). Distance to source population and distance to roads had significant influence at the core female home-range scale. I found a sex-based difference in annual and seasonal home-ranges. I also found that bears exhibited response to and selection for specific resources with an affinity toward hardwood stands, particularly young-aged hardwoods. My research illustrates the importance of analyzing resource selection at multiple scales to gain a full understanding of parameters that influence the recolonization of a bear population.

The Cooperative Alleghany Bear Study (CABS) was a 10-year study conducted on 2 areas and designed to investigate the ecology of a hunted population of American black bears (Ursus americanus) in the Alleghany Mountains of western Virginia. Over the course of our research, we handled 1,041 individual bears >18 months old and gathered reproductive data from females during 424 bear-winters. My analyses of 183 litters indicate that reproductive rates were high with relatively large litters (mean = 2.49 cubs / litter) and younger (3–4-year-old) females having smaller litters than older (> 5 years old) females. Overall cub sex ratios did not differ from 1M:1F; however, female cubs were over-represented in 4-cub litters. Most cubs were born in January (mean = January 17) and younger females had later parturition dates than older females. Bears on our study areas had relatively early ages at primiparity (mean = 3.8 years old) and few missed reproductive opportunities. Hard mast failure apparently resulted in periodic reproductive failures and subsequent reproductive synchrony, which I tracked using 5 indices. The amplitude of oscillations in reproductive synchrony dampened through time after each synchronizing event. The population contained substantially more females than males; however, males were more vulnerable to trapping than were females. Population size was determined using genetic and photographic capture-recapture estimators. Density estimates were relatively high and approached 1 bear / km2. Annual survival rates were high for cubs (0.87) and females (0.91). For males, annual survival rates were lower, particularly for 1–3-year-olds (0.57). Excluding hunting mortality, natural survival rates were high (0.98) for all >1-year-old bears on our study areas. The results of Leslie Matrix and Program RISKMAN models indicated a growing population. A Leslie Matrix model incorporating the effects of a 5-year-cyle of mast-failure-induced reproductive failure yielded a lambda = 1.13. To reach the objective of 0 population growth prescribed for some areas of Virginia, increased levels of hunting mortality on adult (>3-year-old) females would likely be necessary. / Ph. D.

The Cooperative Alleghany Bear Study (CABS) was initiated in 1994 by the Virginia Department of Game and Inland Fisheries (VDGIF) and the Virginia Polytechnic Institute and State University (VPI&SU) to investigate population dynamics on Virginia's hunted bear population. CABS personnel handled 746 different bears (1.5M:1F) 1,368 times on its northern study area during June 1994 to September 2000. The sex ratio for summer captures was 1.5M:1F, which differed from 1:1 (n = 1,008, Z = 6.17, P < 0.0001). Sex ratios for the summer captures ranged considerably among years (÷2 = 23.92, df = 6, P = 0.0005) and among age classes (÷2 = 119.22, df = 4, P < 0.0001), with the largest discrepancy among yearlings (5.7M:1F). The sex ratio among captured adults favored females (0.6M:1.0F ). Average age for all captured bears was 3.87 ± S.E. 0.12 years; females (n = 309) averaged 5.20 ± S.E. 0.16 and males (n = 402) averaged 2.84 ± S.E. 0.14 years (t = 10.92, df = 709, P < 0.001). Litter size averaged 2.35 cubs / litter over the 6-year period and sex ratio did not differ from 1:1 (n = 183, Z = 0.74, P = 0.461), but varied among years (÷2 = 16.61, df = 5; P = 0.005). Three-hundred-and-seventy-six (164M, 212F) of 746 captured individuals were equipped with radio-transmitters. The ratio of radio-collared bears fluctuated from 2.6 F:1M (1998) to 8.6F:1M. We tested a radio-collar effect on survival as a covariate and found a significantly higher survival for radio-collared adult and 3-year-old females in the first 3 years of the study (c2 = 6.64, 1 df, P = 0.01). Estimates using the Kaplan-Meier staggered entry showed survival rates for females (adults = 0.993, subadults = 0.997) higher than for males (adults = 0.972, subadults = 0.917). Estimates using the mark-dead recoveries data showed survival rates of 0.840 for adult females (0.714 for 2-year-olds) and 0.769 for adult males (0.335 for 2-year-olds). We observed 34 mortalities of radio-collared bears for which hunting mortality accounted for 85%. Four natural mortalities included a 5-year-old female and a 2-year-old male that were killed by other bears, and a 14-year-old and 2-year-old female that died of unknown causes. Among the ear-tagged sample, 2-year-old males experienced the highest mean harvest rate of 45%, with a high of 65% mortality in 1996. Among females, 2-year-olds were most vulnerable with a harvest mortality rate of 22% a year. Population modeling indicated that population growth rate of black bears in Virginia is most sensitive to changes in adult female reproduction and survival. With current survival and reproductive estimates, simulation indicated that adult female harvest has to increase 44% from current levels to stabilize population growth. Population size estimates using Bowden's estimate for mark-resight data for a 100 km2 sub-area on the northern study area ranged from 83-131 animals during 1998-2000. When adjusted for the proportion of time radio-collared bears spent on the study area population estimates fell to 63-96 bears. Using the Lincoln-Petersen estimate with Chapman's modification, black bear population estimates for the northern study area ranged from 582-1,026 animals during 1994-1999 on the 860 km2 area. Visitation rates to bait station sites correlated well with changes in population size estimates (n = 5, r = 0.97, P = 0.007). Black bear harvest in general was weakly correlated to change in population size (n = 6, r = 0.49, P = 0.328), however, archery harvest was highly correlated (n = 6, r = 0.95, P = 0.002). The monitoring indices showed all showed the same trends. We recommend a combination of them rather than relying on only a single index for monitoring Virginia's black bear population. During winters 1995–2001, located 215 dens of radio-collared bears; 68% were in trees. Ground dens used by bears included nests in laurel thickets, excavations, brush piles, and rock cavities. The proportion of bears using tree dens did not differ between our 2 study areas (n = 203, ÷ 2 = 1.63, 1 df, P = 0.202), the proportion of females using tree dens (65%, n = 127) was greater than that of males (33%, n= 15; ÷ 2 = 10.69, 1 df, P < 0.001) on the northern study area. Sex and age were significant factors in determining the type of den a bear selected. Twenty-six of 66 individual bears handled for 2–6 consecutive years consistently used tree dens, 8 were faithful to rock cavities, and only 4 regularly used ground dens for denning. Twenty-eight bears (42.4%) switched den types over the 6–year period, primarily from tree dens to rock cavities. / Ph. D.

Reported survival rates, dates of family breakup, and dispersal patterns for yearling and subadult bears in hunted black bear (Ursus americanus) populations in North America are scarce. We estimated survival rates of yearling and subadult black bears from a hunted population in western Virginia during 1999 - 2002. We captured and marked 307 different individual yearling and subadult bears on 2 study sites, and attached ear tag transmitters or radio collars to 54 (34M : 20F) 1-year-old, 52 (23M : 29F) 2-year-old, and 35 (8M : 27F) 3-year-old black bears. We used the known fate model in program MARK to estimate annual, non-hunting, and hunting season survival for radio-marked bears of each age and sex class. Additionally, we used mark-recapture data in the recaptures only, dead recoveries, and Burnham's combined models within program MARK to estimate annual survival for each age and sex class. One-, 2-, and 3-year-old female survivorship was 0.87 (95% C.I. 0.78 - 0.92), while 1-year male survivorship was 0.32 (95% C.I. 0.20 - 0.47), and 2- and 3-year-old male survivorship was 0.59 (95% C.I. 0.47 - 0.71) from the Burnham's combined model. Survival rates for 1-year-old females (χ2 = 6.20, P = 0.01) and 2-year-old females (χ2 = 7.74, P = 0.01) were higher than males in each age category, respectively. However, we detected no difference between 3-year-old females and 3-year-old males (χ2 = 2.61, P=0.11), likely due to small sample size of males (n = 4). Low yearling and subadult survival is not likely a cause for alarm due to the importance of adult female survival to population growth and the promiscuous mating system in black bear populations. Family breakup is an important event in the life history of black bears, marking the initial dispersal and home range construction of yearling bears, and perhaps marking the timing of estrus and breeding opportunities for adult females. We monitored 6 black bear family groups with 12 yearlings (6M : 6F) to determine the timing of family breakup; we intensely monitored 3 of the family groups to document home range establishment and movements by 5 subadult bears (2M : 3F) following separation from their mothers. Estimated dates of family breakup were 28 May and 2 June. Family breakups occurred before peak dates of estrus on our 2 western Virginia study areas. We detected 2 reassociations between a mother and her yearling offspring. Following family breakup, female yearlings (n = 3) remained within or partially on their mothers' home range while subadult males (n = 2) left their mothers' home ranges. All yearlings (n = 5) shared ≥50% of post-breakup home range with their mothers. We studied the movements of 31 (11M : 20F) subadult black bears born on our 2 study areas in western Virginia and 70 (44M : 26F) subadult bears captured during the summer on the study areas for dispersal. No radio-marked, resident, subadult female bears exhibited dispersal behavior while 3 of 11 (27%) radio-marked, resident, subadult males dispersed (P = 0.04). Resident and summer capture male bears moved greater distances than females from yearling den location (χ2 = 8.54, P = 0.01, df = 2) or summer capture location (χ2 = 22.02, P < 0.01, df = 2); no female moved > 10 km between initial and final locations (x = 2.7 km, range 0.2 - 9.0 km). The greatest subadult male movement was 80 km (x = 13.4 km, range 0.6 -0.80 km), and dispersal movements primarily occurred within the 1 and 2-year-old age classes. Direction of movement between initial and final locations for dispersing bears was not random (Rayleigh's r = 0.56, P = 0.02); bears appeared to follow the orientation of the predominant ridgelines and avoided leaving the national forest. / Master of Science

Prior to European settlement, black bear (Ursus americanus) were far less abundant in the state of California. Estimates from statewide harvest data indicate the California black bear population has tripled in the last 3 decades. Bears inhabit areas they formally never occurred (e.g., urban environments) and populations that were at historically low densities are now at high densities. Though harvest data are useful and widely used as an index for black bear population size and population demographics statewide, it lacks the ability to produce precise estimates of abundance and density at local scales or account for the numerous bears living in non-hunted areas. As the human population continues to expand into wildlife habitat, we are being forced to confront controversial issues about wildlife management and conservation. Habituated bears living in non-hunted, urban areas have been and continue to be a major concern for wildlife managers and the general public. My objective was to develop DNA-based capture-mark-recapture (CMR) survey techniques in wildland and urban environments in Mono County, California to acquire population size and density at local scales from 2010 to 2012. I also compared population density between the urban and wildland environment. To my knowledge, DNA-based CMR surveys for bears have only been implemented in wildland or rural environments. I made numerous modifications to the techniques used during wildland DNA-based CMR surveys to survey bears in an urban environment. I used a higher density of hair-snares than typically used in wildland studies, non-consumable lures, modified hair-snares for public safety, included the public throughout the entire process, and surveyed in the urban-wildland interface as well as the city center. These methods were efficient and accurate while maintaining human safety. I determined that there is likely a difference in population density between the urban and wildland environments. Population density was 1.6 to 2.5 times higher in the urban study area compared to the wildland study area. Considering the negative impacts urban environments can have on wildland bear populations, this is a serious management concern. The densities I found were similar to those found in other urban and wildland black bear populations. The baseline data acquired from this study can be used as part of a long-term monitoring effort. By surveying additional years, population vital rates such as apparent survival, recruitment, movement, and finite rate of population change can be estimated.

The niche concept provides a tractable measure of the ecological roles and requirements of organisms, which can inform our understanding of the patterns of biodiversity, and subsequently, direct conservation policy. Although niche is most commonly considered for species, variation nested within lower hierarchies of biological organization (i.e., phenotypes, genotypes) also contributes to maintaining biodiversity. Herein I examine spatial and dietary niche variation among and within species in a consumer–resource system where resources and competition are structured by a heterogeneous environment. An underlying theme of this dissertation was developing research through a community-engaged approach that not only contributed to conceptual advancements in niche theory but also to applied conservation priorities. The marine archipelago of the central coast of British Columbia, Canada structures salmon (Oncorhynchus spp.) resources and the inter- and intraspecific competitive context for coastal grizzly (Ursus arctos) and black bears (Ursus americanus). This assembly of ursids represents nested levels of biological organization (i.e., species, phenotypes (white vs black-coated morphs of black bears) and genotypes (dominant homozygote black-coated black bears, heterozygote black-coated black bears, recessive homozygote white-coated ‘Spirit’ black bears)), which allows for investigation into niche variation across and within species. I investigated niche variation using a suite of non-invasive methods. Local and Traditional Ecological Knowledge (LEK/TEK) provided complementary information to genetic and stable isotope (13C and 15N) data from hair samples. First, I investigated changes in the spatial niche of coastal grizzly bears. By combining western scientific approaches with TEK/LEK interviews I found the range of coastal grizzly bears has expanded westward onto several coastal islands. The economic, cultural, and ecological impacts of this shift in spatial niche are not yet understood. Second, I tested hypotheses related to variation in the foraging niche of black bears in response to the competitive environment and salmon resource availability. I found that grizzly bear presence reduced the proportion of salmon in black bear diets by ~40%. I also found that salmon species diversity, and not biomass abundance, was positively correlated to salmon in black bear diets. This highlights the importance of resource diversity to consumers beyond the consideration of abundance. Third, I explored spatial niche patterns of Spirt bears in relation to protected areas. I found that landscape-level Spirit bear allele frequency and population estimates were lower than previously reported. Approximately ~50% of Spirit bear allele hotspots corresponded to protected areas. This finding suggests Spirit bears are rarer and less protected than previously assumed. Finally, I tested hypotheses related to niche variation between phenotype and genotypes of Spirit bear populations. I found both phenotypes and genotypes diverged in foraging niche, with Spirit bears and black-coated heterozygotes having elevated stable isotope signatures compared to black-coated homozygotes. This result supports the role of ‘multi-niche’ mechanisms in maintaining this rare polymorphism. Results from all chapters contributed to land- and marine-use stewardship efforts of collaborating First Nations. Collectively, this dissertation offers novel contributions towards understanding how niche variation at multiple levels of biological organization can contribute to conservation planning. / Graduate / 2020-04-04

Human influence on the environment is becoming increasingly pervasive across the globe, and can drastically impact ecological patterns and processes. For many terrestrial wildlife species, human influence can fragment critical habitat, increase mortality, and threaten habitat connectivity and ultimately the persistence of wildlife populations. This dissertation aims to use multiple conservation ecology methods and tools to test the impact of human influence on the population dynamics of a large carnivore in a human-dominated landscape. To assess the impact of human activity on carnivore ecology, a series of empirical studies were conducted on a small population of American black bear (Ursus americanus) in the Western Great Basin, USA. A long-term dataset including geographic locations of animal habitat choices as well as mortality locations were used in multiple statistical models that tested the response of black bears to human activity. These analyses were conducted at multiple spatial and temporal resolutions to reveal nuances potentially overlooked if analyses were limited to a single resolution. Individual studies, presented as dissertation chapters, examine the relationships between human activity and carnivore ecology. Collectively, the results of these studies find black bear ecology to be highly sensitive to the magnitude and spatial composition of human activity in the Lake Tahoe Basin, observable at both coarse and fine spatial resolutions. The results presented in this study on the influence of human activity on large carnivore population dynamics allow for a more thorough understanding of the various ways common conservation ecology methods and tools can be used to evaluate human-wildlife relationships.

The primary goals of this research were to investigate 3 ecological factors influencing black bear (Ursus americanus) foraging behavior on an Alaskan salmon (Oncorhynchus spp.) stream: fish availability, social dynamics, and human activity. Over 900 observation hours were Jogged at 2 falls from July !-September I 1993-1995; the lower falls were open to public for wildlife viewing, but the upper falls were restricted to research personnel. In general, black bears responded to differences in fish accessibility on both spatial and temporal scales. All years of the study, 3 indices of bear activity (bear minutes, bear numbers, bout duration) and fish capture rates were significantly higher (all Ps <0 I 0) at the upper falls where fishing opportunities were more abundant. Furthermore, seasonal variation in black bear density was indicative of fluctuations in fish accessibility: bear numbers were highest midseason when fish appeared more abundant, but decreased towards the end of the summer. Although many bears fished within 3 to 5 m of one another, the majority of intraspecific interactions (65-75%) were benign as opposed to agonistic with a preponderance of "passive deferrals" where bears detoured around rather than confronted conspecifics. Only 5. 7% of all interactions resulted in reversals or circularity, providing some evidence for a linear dominance hierarchy. The most dominant bears fished where salmon were highly accessible for longer periods of time, therefore capturing more fish than subordinates each year. Of interspecific interactions, black bears were more likely to be displaced when encountering brown bears on the same side rather than opposite sides of the creek. Of 24 recognized bears, 71% were observed from 75-100% of the time at the upper falls; only 8% (2 females) fished solely at the lower falls. Five of 8 bears that fished exclusively at the upper falls (all large males) appeared wary of researchers upon their arrival. Based on quantile regression analyses, we found that visitor numbers acted as a ceiling on fishing duration of black bears at the lower falls in 1994 and 1995. Furthermore, 2 habituated bears seen frequently at the lower falls spent less time in view (maximum values) as visitor group size increased.

Conflicts between humans and black bears (Ursus americanus) jeopardize the safety of both humans and bears, especially when bears become food-conditioned to anthropogenic food sources in areas such as campgrounds. Interest in using non-lethal techniques, such as aversive conditioning, to manage such conflicts is growing. I conducted a captive experiment at The Wildlife Science Center in Minnesota and two field experiments in the La Sal Mountains, Utah, to investigate the effects of taste aversion conditioning using thiabendazole (TBZ) with a novel flavor cue and food removal on black bear food consumption and visitation to human food sources. In 2007, I conducted food trials with 6 captive black bears (3 control, 3 treatment). Controls received 1 kg baked goods scented with a peppermint-canola oil mixture and treatments received 1 kg baked goods also scented with a peppermint-canola oil mixture but mixed with 10-20 g TBZ. In the 2007 field experiment, I baited 24 field sites with 300 g of baked goods during a baseline phase for approximately 3 weeks. Half of these sites were then treated with 10 g of TBZ and camphor during a treatment phase for 4 weeks. In 2008, I baited 22 sites with 300 g of baked goods during a baseline phase for approximately 4 weeks. I then removed food and discontinued baiting at half of the sites for 4 weeks. Infrared cameras and barbed-wire hair snags were established at field sites to document bear visitation. I did not establish taste aversion in treated bears in captivity and bears fully consumed food in the majority of trials. Treating food supplies with 10 g TBZ and camphor flavor did not significantly reduce bear visitation (P = 0.615) or food consumption at field sites (P = 0.58). However, I observed a significant reduction in bear activity at sites where food was removed (P = 0.006). Potential reasons for my failure to reduce bear visitation using thiabendazole include insufficient conditioning, reluctance of bears to desist in investigating sites that previously contained untreated food, and masking of a treatment effect due to continued encounters of sites by new individuals.