I tested the efficacy of aversive conditioning (AC) and conditioned taste aversion (CTA) on American black bears (Ursus americanus) in Whistler, British Columbia. Black bears subjected to 3-5 day AC programs responded by increasing their wariness toward humans, while control bears habituated. Bears were located closer to human developments during daylight hours after AC treatments. However, there was no difference in the proportion of utilization distribution that overlapped with developed areas in control or AC-treated bears. CTA may be effective for managing specific attractants that are difficult to secure from bears. Bears appeared to distinguish between baits treated with thiabendazole and baits that were not treated, but by using a protocol that caused severe illness and left the source of illness in doubt, I induced taste aversions to apples in 4 bears. Using both AC and CTA may help wildlife managers mitigate human-wildlife conflicts non-lethally more effectively. / Ecology

For years, bear hunters have provided an unknown amount of food to black bears <i>(Ursus americanus)</i> in Virginia, supplementing their natural food supply. Possible effects of feeding bears can be negative, such as food conditioning and habituation to people, or positive, such as enhanced or sustained reproductive rates, especially in years of mast crop failure. In July 1999, the Virginia Department of Game and Inland Fisheries (VDGIF) adopted a regulation recommendation that prohibited the feeding of wildlife on national forest and department-owned lands. We mailed a survey to all members of the Virginia Bear Hunters Association (VBHA, n = 459) to determine the amount of food provided to bears by bear hunters in Virginia between 1 July 1998 and 30 June 1999. Survey response rate was 52%. One hundred thirteen of 238 (47.5%) survey respondents spent over $18,000 on supplemental food in one year, averaging $163/person. One hundred twenty-eight respondents reported cumulatively providing nearly 3 million kilograms of food to bears between 1 July 1998 and 30 June 1999. Whole-shelled corn, pastries, and grease accounted for 58% of the total food by weight; however, whole-shelled corn, pastries, and bread were the 3 most common foods offered. Feeding occurred in 25 counties in Virginia, primarily during July, August, and September. Rockingham County had the highest proportion of feeders (47%), followed by Giles (15%), Augusta (14%), Craig (9%) and Montgomery (9%) Counties. Accordingly, Rockingham County received the highest proportion of food (42%), followed by Craig (8%), Giles (7%), Montgomery (6%), and Tazewell (6%) Counties. The low survey response rate, coupled with the fact that 48% of sampled nonrespondents fed bears, suggests that the total amount of annual feeding in Virginia may exceed the total determined during this study. However, the possibility of an avidity bias, in which a higher response by the more avid feeders would erroneously inflate a total estimate extrapolated to include feeding by nonrespondents, cannot be eliminated. Little work has been done pertaining to digestibilities of black bear foods, particularly those in the eastern United States. We determined digestibilities for several important eastern black bear foods, including northern red oak <i>(Quercus rubra)</i>, white oak <i>(Q. alba)</i>, and chestnut oak acorns <i>(Q. prinus)</i>, squawroot <i>(Conopholis americana)</i>, high-protein dogfood, shelled corn, and doughnuts. All diets were evaluated for nutrient content as well as percent dry matter digestibility of crude protein, ether extract (a measure of fat), and gross energy. Diets we suspected were high in fiber were additionally evaluated for neutral detergent fiber or acid detergent fiber content and digestibility. Feeding trials were conducted with 1 male and 4 female captive bears during fall 1998, and 5 female captive bears during fall 1999, at the Center for Ursid Research, Blacksburg, Virginia. Acorns and squawroot were high in fiber (45-62%) and moderate to low in protein (5-7%). Fat content was high in doughnuts (24.7) and northern red oak acorns (12%), moderate in dogfood (8.2%) and white oak acorns (4.7%), and relatively low in shelled corn, chestnut oak acorns, and squawroot (1.3-3.5%). Crude protein was high in dogfood (29%) and moderate in all other diets (4.7-8.8%). Neutral detergent fiber content was high in squawroot and all acorn types (45-62.4%). Acid detergent fiber was high in squawroot (47%) and moderate in dogfood (9%). In 1998, crude protein digestibility was high in doughnuts (86%), moderate in shelled corn and white oak acorns (50-64%), and negligible in northern red oak acorns (-39%). Ether extract digestibility was high in doughnuts, red oak acorns, and white oak acorns (80-97%), and moderate in shelled corn (67%). Fiber digestibility was tested only on northern red oak and white oak acorns, and was moderate (62% and 68%, respectively). In 1999, crude protein digestibility was high in dogfood, dogfood mixed with squawroot, and doughnuts (75-85%); moderate in shelled corn, squawroot, and white oak acorns (43-58%); and low to negligible in chestnut oak and northern red oak acorns (-13-6%). Ether extract digestibility was moderate in shelled corn (64%) and squawroot (60%), and high in all other diets (79-97%). Neutral detergent fiber digestibility was moderately high in all acorn types (54-71%). Acid detergent fiber digestibility was moderate for dogfood (66%), and associative effects occurred between the fiber in squawroot and dogfood, resulting in negative fiber digestibility in squawroot determined by difference (-19%). A luxury not always realized in wildlife management is the ability to investigate possible effects of management or policy changes prior to their employment. The amount of food provided to bears by bear hunters in Virginia may have been more substantial than previously believed, and likely provided bears with a high energy, stable food source that supplemented their natural food supply. We did not have the opportunity to study the effects of removing that food source on public lands prior to the regulation change; however, the opportunistic feeding strategy of bears, coupled with sufficient mast production at the time of the regulation change, likely softened any negative effects that may have occurred as a result of the removal of supplemental food as a regular food source for some bears. / Master of Science

The planned widening of U.S. Highway 17 along the east boundary of Great Dismal Swamp National Wildlife Refuge (GDSNWR) and a lack of knowledge about the refuge's bear population created the need to identify potential sites for wildlife crossings and estimate the size of the refuge's bear population. I collected black bear hair in order to collect DNA samples to estimate population size, density, and sex ratio, and determine road crossing locations for black bears (Ursus americanus) in GDSNWR in southeastern Virginia and northeastern North Carolina. I also investigated bear/vehicle collisions to determine patterns of road crossing. Genetic analysis of 344 hair samples collected on 2 trapping grids identified 85 unique individuals which I used in a mark-recapture analysis. Estimated population size on the trapping grids was 105 bears (95% CI = 91-148) and average density was 0.56 bears/km². This density estimate projected over the entire Great Dismal Swamp ecosystem yielded a population estimate of 308 bears (550 km2 X 0.56 bears/km²). Similar population estimates generated by Hellgren (1988), Tredick (2005), and this study suggest a stable bear population in the Great Dismal Swamp ecosystem over a 20-year period. I erected a 2.3-kilometer long strand of barbed wire along U. S. Highway 17 to monitor road crossing patterns near the Northwest River drainage. Genetic analysis identified 6 bears (4 males, 1 female, 1 unknown) that apparently crossed the highway in a 10-month period. Five of 6 bears deposited hair in a 171-m section which included the Northwest River corridor. The 6 bears detected crossed the road at least 11 times. I investigated 10 reports of bear/vehicle collisions on the periphery of the refuge from June 2000 to May 2002. Six bears (4M:1F:1 unknown) were confirmed killed during this time period. Based on reported bear/vehicle collisions from Hellgren (1988), the Virginia Department of Game and Inland Fisheries database, and this study, a minimum of 4 to 5 bears are struck by vehicles each year on the periphery of the refuge. I identified 2 areas of multiple bear/vehicle collisions: highway 58 on the north side of the refuge near Hampton Airport and Highway 17 on the eastern side of the refuge in the vicinity of the Northwest River corridor. / Master of Science

During 1999-2001, potential den trees and denning success of black bears was investigated on industrial forest lands and national forest lands in Virginia and West Virginia. One hundred and fifty seven potential den trees were found on five study areas, 135 on national forest lands and 22 on the industrial forest lands. Twenty-seven hollow potential den trees were found, 22 on national forest lands and 5 on industrial forest lands. Densities of potential den trees ranged from 12.5/km2 to 437.5/km2 on the national forest lands and on the industrial forest lands the densities ranged from 0-187.5/km2. There were significantly higher densities (F1, 69=5.86, P=0.0181) of potential den trees on the national forest land than on the industrial forest land. There were also significantly (F=2, 68=7.86 P=0.0008) higher densities of hollow potential den trees based on the stand age class. Denning success for females expected to have cubs was 98% (n=46) in tree dens on national forest lands and 100% (n=8) on industrial forest lands. Denning success for females expected to have cubs was 76% (n=55) in ground dens on national forest lands and 80% (n=5) in ground dens on industrial forest lands. Females expected to have cubs on the national forest lands had an overall denning success of 89% (n=80) and on industrial forest lands there was overall, 92% (n=13) denning success. Chi-square tests showed that abandonment of dens by bears was significantly higher (x2=19.02, 1df) in ground dens than in tree dens. Litter sizes were not different from national forest lands and industrial forest lands (t=-0.36, 44df, P=0.84). The mean litter sizes on the national forest lands was 2.55 (SE=0.16) cubs per litter and on the industrial forest land 2.4 (SE=0.22) cubs per litter. / Master of Science

An outbreak of Deidamia inscriptum (Lettered Sphinx Moth) caterpillars was noted in northeast Tennessee where Oxydendrum arboreum (Sourwood) trees were defoliated. Nearly all published literature and online resources list only plants in the grape family (Vitaceae) as larval food plants. Food-plant preference trials using fresh leaves of 3 woody plant species showed that Deidamiacaterpillars from this region had a preference for Sourwood over Parthenocissus quinquefolia(Virginia Creeper), and rejected Acer rubrum (Red Maple), a non-host species. Ursus americanus(Black Bear) were feeding on the caterpillars as evidenced by bent and broken Sourwood saplings bearing claw marks and by abundant sphingid remains in bear scat.

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.