141 research outputs found

    Monitoring wildlife-vehicle collisions: analysis and cost-benefit of escape ramps for deer and elk on U.S. Highway 550

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    Prepared for: Colorado Department of Transportation, Division of Transportation Development, Applied Research and Innovation Branch. Prepared in cooperation with the US Department of Transportation, Federal Highway Administration.Report No. CDOT-2015-5.May 2015.Includes bibliographical references (pages 35-37).Wildlife fencing along highways can lower wildlife-vehicle collision rates by excluding animals from the road right-of-way. Still, animals can breach fencing and end up trapped within the fencing along the highway right-of-way, exposing wildlife and motorists to the risk of collision. Wildlife escape ramps are designed to allow trapped animals safe passage out of the right-of-way. Few recommendations exist on effective design of escape ramps and monitoring data are limited. We investigated the usage levels, escape success, wildlife-vehicle collisions, and design of 11 escape ramps and two escape jumps along an eight-mile stretch of U.S. Highway 550 near Ridgway, Colorado. Our goals were to 1) relate usage levels and escape success to ER structure design and its surrounding environmental characteristics, 2) describe the animal use of ER in the study area, 3) conduct a cost-benefit analysis for escape ramp construction and 4) provide recommendations regarding ER design and WVC based on data collected.Study No: 032.47

    Sod-Busting and Sage Grouse: Estimating Historical Impacts and Planning for the Future

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    A conservation strategy for Greater sage grouse (Centrocercus urophasianus) in the Great Plains, where conversion of native rangeland to cropland is an accelerating agent of land use change, must anticipate impacts of future sod-busting on populations. We use resource selection functions (RSF) to estimate the scale and magnitude of the effect of sod-busting on the distribution of sage-grouse leks in the Great Plains Management Zone and estimate impacts of future cropland expansion. Active leks were used to develop a distribution envelope based on topographic and climatic variables from which random pseudo-absences were drawn to fit a used-available RSF. Models with proportion cropland at scales from 800 m to 8.5 km were compared using AICc to determine the most supported scale at which cropland influences lek occurrence. Finally, we develop a buildout scenario based on a cropland suitability model to estimate potential impacts of future sod-busting on known leks. Negative effects of cropland on lek occurrence were evident at all scales tested. The 6.4 km scale was most supported, and impacts were severe, with the relative probability of lek occurrence falling by 50% when about 20 percent of the landscape within 6.4 km was in cropland. These results, which highlight the large scale and magnitude of impacts of cropland on sage grouse populations, are needed to evaluate the potential contribution of conservation easements and land-use policy to local and range-wide sage-grouse conservation goals. Population-level benefits of targeted conservation implementation are explored

    What Is the Proper Method to Delineate Home Range of an Animal Using Today’s Advanced GPS Telemetry Systems: The Initial Step

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    The formal concept of an animal’s home range, or derivations thereof, has been around for over half a century (Burt 1943). Within this time frame there have been countless published studies reporting home range estimators with no consensus for any single technique (Withey et al., 2001; Laver & Kelly 2008). Recent advances in global positioning system (GPS) technology for monitoring home range and movements of wildlife have resulted in locations that are numerous, more precise than very high frequency (VHF) systems, and often are auto correlated in space and time. Along with these advances, researchers are challenged with understanding the proper methods to assess size of home range or migratory movements of various species. The most acceptable method of home-range analysis with uncorrelated locations, kernel-density estimation (KDE), has been lauded by some for use with GPS technology (Kie et al., 2010) while criticized by others for errors in proper bandwidth selection (Hemson et al., 2005) and violation of independence assumptions (Swihart & Slade 1985b). The issue of autocorrelation or independence in location data has been dissected repeatedly by users of KDE for decades (Swihart & Slade 1985a; Worton 1995, but see Fieberg 2007) and can be especially problematic with data collected with GPS technology

    Education is not a panacea for reducing human–black bear conflicts

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    The long-term survival of carnivores is greatly challenged by conflict with humans. Such conflicts can bolster risk perceptions,lower tolerance, and lead to support of lethal control of carnivores.To address this ubiquitous challenge and improve conservation outcomes specifically for American black bears (Ursus americanus),Marley et al. (2017) used an agent based model to explore how management strategies could alter the use of the urban environment by bears, and subsequently reduce the occurrence of human-bear conflicts. Management strategies entailed education only, where people were taught to remove food attractants, apply aversive conditioning, or both, and the authors considered different spatial configurations of implementation (border, clustered, and random). Education resulting in food removals led to a reduction in the food values of urban cells. Education resulting in aversive conditioning led to increased vigilance by humans and increased probability of a bear being deterred, which in turn, resulted in the bear moving a significant distance away from the urban cell as well as a reduced memory value for those cells. Food and memory cell values deter-mined the movement choices of the bears in the next time step, and cell visits along with the occurrence of deterrence events deter-mined the habituation and food conditioning status of bears. When bears reached thresholds determined by the authors, they changed their status from ‘graduated’ to ‘survival’ and eventually ‘conflict’ status, which was modeled as a function of independent variables including initialization conditions (e.g., percent urbanization; Table5 of Marley et al., 2017) and management strategies (e.g., clustered vigilance; Fig. 5 of Marley et al., 2017). The authors concluded that,compared to a ‘no teaching’ scenario, education works to reduce‘conflict’ bears in urban areas, and that teaching people to apply aversive conditioning was the most effective strategy

    Foraging ecology of black bears in urban environments: guidance for human-bear conflict mitigation

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    Includes bibliographical references (pages 10-13).Urban environments offer wildlife novel anthropogenic resources that vary spatiotemporally at fine scales. Property damage, economic losses, human injury, or other human-wildlife conflicts can occur when wildlife use these resources; however, few studies have examined urban wildlife resource selection at fine scales to guide conflict mitigation. We studied black bears (Ursus americanus) in the urban area of Aspen, Colorado, USA from 2007 to 2010 to quantify bear foraging on natural and anthropogenic resources and to model factors associated with anthropogenic feeding events. We collected fine-scale spatiotemporal data by tracking GPS-collared bears at 30-min intervals and backtracked to bear locations within 24 hours of use. We used discrete choice models to assess bears' resource selection, modeling anthropogenic feeding (use) and five associated random (availability) locations as a function of attributes related to temporally changing natural (e.g., ripe mast) and human (e.g., garbage) food resources, urban characteristics (e.g., housing density), and land cover characteristics (e.g., distance to riparian area). We backtracked to 2,675 locations used by 24 bears and classified 20% as foraging locations. We found that bears foraged on both natural and anthropogenic food sources in the urban environment, with 77% of feeding events being anthropogenic. We documented inter- and intra-annual foraging patterns in which bears foraged extensively in urban areas when natural food production was poor, then switched to natural food sources when available. These patterns suggest that bears balance energy budgets and individual safety when making foraging decisions. Overwhelmingly, garbage was the main anthropogenic food source that bears used. Selection of foraging sites was not only influenced by presence of garbage but also by proximity to riparian habitat and presence of ripe anthropogenic fruit trees. We found that while 76% of the garbage containers at random locations were bear-resistant, 57% of these bear-resistant containers were not properly secured. We recommend conflict mitigation focus on reducing available garbage and anthropogenic fruit trees, particularly near riparian areas, to make urban environments less energetically beneficial for foraging. Additionally, deploying bear-resistant containers is inadequate without education and proactive enforcement to change human behavior to properly secure garbage and ultimately reduce human-bear conflict.Published with support from the Colorado State University Libraries Open Access Research and Scholarship Fund

    American black bear den-site selection and characteristics in an urban environment

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    Selection of den sites is a crucial aspect of American black bear (Ursus americanus) life history. High-quality dens provide thermal insulation, protection from disturbance, suitable environment for parturition and cub development, and proximity to available forage upon emergence. Black bears are increasingly coexisting with people in human-dominated landscapes; however, little is known about whether urban environments influence characteristics of dens and den site selection. Our objective was to determine the effect of housing density (a proxy for human activity and availability of anthropogenic resources) on selection of den sites in years of good and poor natural forage.We additionally compared size, shape, and location of dens of males and females to describe den characteristics and explorewhether differences existed between males and females. We revisited 34 den locations detected during a 6-year (2005–2010) urban black bear study in Aspen, Colorado, USA, and measured den entrance and den volume. We fit a conditional logistic regression model using a resource selection function framework to determine the importance of housing density and other landscape variables (elevation, slope, aspect, and vegetation type) associated with den site selection. Slope was the best predictor of den site selection and there was no relationship between den selection and housing density, indicating that black bears were neither avoiding nor seeking urban areas for denning. Dens were smaller for females (x =3.30m3, SE = 1.94, n = 22) than for males (x = 7.56 m3, SE = 3.31, n = 8), supporting the idea that females have greater constraints in den characteristics, possibly related to cub development and security from predation or because females generally are smaller than males

    Human development and climate affect hibernation in a large carnivore with implications for human–carnivore conflicts

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    1. Expanding human development and climate change are dramatically altering habitat conditions for wildlife. While the initial response of wildlife to changing environmental conditions is typically a shift in behavior, little is known about the effects of these stressors on hibernation behavior, an important life-history trait that can subsequently affect animal physiology, demography, interspecific interactions and human-wildlife interactions. Given future trajectories of land use and climate change, it is important that wildlife professionals understand how animals that hibernate are adapting to altered landscape conditions so that management activities can be appropriately tailored. 2. We investigated the influence of human development and weather on hibernation in black bears (Ursus americanus), a species of high management concern, whose behavior is strongly tied to natural food availability, anthropogenic foods around development and variation in annual weather conditions. Using GPS collar data from 131 den events of adult female bears (n = 51), we employed fine-scale, animal-specific habitat information to evaluate the relative and cumulative influence of natural food availability, anthropogenic food and weather on the start, duration and end of hibernation. 3. We found that weather and food availability (both natural and human) additively shaped black bear hibernation behavior. Of the habitat variables we examined, warmer temperatures were most strongly associated with denning chronology, reducing the duration of hibernation and expediting emergence in the spring. Bears appeared to respond to natural and anthropogenic foods similarly, as more natural foods, and greater use of human foods around development, both postponed hibernation in the fall and decreased its duration. 4. Synthesis and applications. Warmer temperatures and use of anthropogenic food subsides additively reduced black bear hibernation, suggesting that future changes in climate and land use may further alter bear behavior and increase the length of their active season. We speculate that longer active periods for bears will result in subsequent increases in human–bear conflicts and human-caused bear mortalities. These metrics are commonly used by wildlife agencies to index trends in bear populations, but have the potential to be misleading when bear behavior dynamically adapts to changing environmental conditions, and should be substituted with reliable demographic methods

    The Carrot or the Stick? Evaluation of Education and Enforcement as Management Tools for Human-Wildlife Conflicts

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    Evidence-based decision-making is critical for implementing conservation actions, especially for human-wildlife conflicts, which have been increasing worldwide. Conservation practitioners recognize that long-term solutions should include altering human behaviors, and public education and enforcement of wildlife-related laws are two management actions frequently implemented, but with little empirical evidence evaluating their success. We used a system where human-black bear conflicts were common, to experimentally test the efficacy of education and enforcement in altering human behavior to better secure attractants (garbage) from bears. We conducted 3 experiments in Aspen CO, USA to evaluate: 1) on-site education in communal dwellings and construction sites, 2) Bear Aware educational campaign in residential neighborhoods, and 3) elevated law enforcement at two levels in the core business area of Aspen. We measured human behaviors as the response including: violation of local wildlife ordinances, garbage availability to bears, and change in use of bear-resistance refuse containers. As implemented, we found little support for education, or enforcement in the form of daily patrolling in changing human behavior, but found more support for proactive enforcement, i.e., dispensing warning notices. More broadly we demonstrated the value of gathering evidence before and after implementing conservation actions, and the dangers of measuring responses in the absence of ecological knowledge. We recommend development of more effective educational methods, application of proactive enforcement, and continued evaluation of tools by directly measuring change in human behavior. We provide empirical evidence adding to the conservation managers' toolbox, informing policy makers, and promoting solutions to human-wildlife conflicts

    Indigenous Peoples’ lands are threatened by industrial development; conversion risk assessment reveals need to support Indigenous stewardship

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    Indigenous Peoples are custodians of many of the world’s least-exploited natural areas. These places of local and global socio-ecological importance face significant threats from industrial development expansion, but the risk of conversion of these lands remains unclear. Here we combine global datasets of Indigenous Peoples’ lands, their current ecological condition, and future industrial development pressure to assess conversion threats. To assess vulnerability and risk of conversion, we create an index based on indicators of the strength and security of Indigenous Peoples’ rights to their territories and resources, their representation and engagement in decisions impacting them, and the capital available to support conservation and sustainable development. We find that nearly 60% of Indigenous Peoples’ lands (22.7 million km2) are threatened in 64 countries. Among the 37 countries with the highest threat, socio-economic and political vulnerabilities increase conversion risk, particularly the limited recognition and protection of territorial rights. We suggest strategies and actions to bolster Indigenous Peoples’ self-determination, rights, and leadership to reduce this risk and foster socio-ecological well-being
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