111 research outputs found
Managing Wolf Depredation in the United States: Past, Present, and Future
With the successful recolonization and reintroduction of wolves (Canis lupus) in parts of the western United States (Bangs and Fritts, 1996; Bangs et al., 1998) and the natural expansion of wolves in the upper Midwest (Fuller et al., 1992; Thiel, 2001), managing conflicts between wolves and livestock is a growing issue for livestock producers, resource professionals, and the general public (Mech, 1996). Unlike the coyote, (Canis latrans) where a great deal is known regarding the biology and ecology of depredation and methods for managing it (Knowlton et al., 1999), very little is known regarding patterns and processes of wolves preying on livestock and effective ways to mitigate this conflict. Understanding the ramifications of growing wolf populations for livestock production and successfully managing these problems will require knowledge of depredation patterns, wolf ecology, livestock husbandry, and the effectiveness of different tools and techniques to manage wolves. As wolf populations expand into more agricultural areas (Mech et al., 2000) such knowledge will become increasingly important. Here historic records were compared to current data on wolf depredation rates and wolf management techniques relative to the wolf’s status on the endangered species list. The objectives were to synthesize the history of wolf depredation and management, present current data of wolf impacts on livestock, and speculate on the future management of wolves so that producers can consider the ramifications of a growing wolf population and possible mechanisms for decreasing the threat
Managing Wolf Depredation in the United States: Past, Present, and Future
With the successful recolonization and reintroduction of wolves (Canis lupus) in parts of the western United States (Bangs and Fritts, 1996; Bangs et al., 1998) and the natural expansion of wolves in the upper Midwest (Fuller et al., 1992; Thiel, 2001), managing conflicts between wolves and livestock is a growing issue for livestock producers, resource professionals, and the general public (Mech, 1996). Unlike the coyote, (Canis latrans) where a great deal is known regarding the biology and ecology of depredation and methods for managing it (Knowlton et al., 1999), very little is known regarding patterns and processes of wolves preying on livestock and effective ways to mitigate this conflict. Understanding the ramifications of growing wolf populations for livestock production and successfully managing these problems will require knowledge of depredation patterns, wolf ecology, livestock husbandry, and the effectiveness of different tools and techniques to manage wolves. As wolf populations expand into more agricultural areas (Mech et al., 2000) such knowledge will become increasingly important. Here historic records were compared to current data on wolf depredation rates and wolf management techniques relative to the wolf’s status on the endangered species list. The objectives were to synthesize the history of wolf depredation and management, present current data of wolf impacts on livestock, and speculate on the future management of wolves so that producers can consider the ramifications of a growing wolf population and possible mechanisms for decreasing the threat
Using Resident-Based Hazing Programs to Reduce Human-Coyote Conflicts in Urban Environments
Abstract The concept of hazing (aversive conditioning) is often promoted as a tool for reducing human-coyote (Canis latrans) conflicts in urban environments. Little scientific evidence exists on the effectiveness of hazing, particularly hazing applied by residents (i.e., community-level hazing). Wildlife professionals question if residents will properly and consistently apply hazing techniques and if hazing impacts coyote behavior over short- and long-term periods. We describe two separate efforts designed to encourage residents to haze coyotes in the Denver Metro Area; a citizen-science program and an open space hazing trial. Both efforts were intended to be management techniques that either could be deployed or are already commonly deployed by urban coyote managers. In addition to educating residents about how, when, and how to quantify individual coyote response to hazing efforts, the citizen-science program measured methods used for and short-term impacts of resident-based hazing and the overall impact of resident involvement in the program. The open space hazing trial measured the impact of on-site education tools and begins to assess if posted signs and on-site education efforts change visitor acceptance and behavior around coyote hazing. The citizen-science program targeted a highly engaged audience and required a significant investment of time and attention for both managers and residents. The open space hazing trial targeted the casual park visitor and required little to no investment of time and attention for both managers and residents. The citizen-science program produced 207 trained citizen-scientists that generated 96 documented hazing events. Voice, noise and approach were the hazing methods most commonly deployed by participants. Citizen-scientists recorded hazing responses varying from rapid fleeing of the area to approaching the person doing the hazing, with the most common response being the coyote leaving the area. In the presence of domestic dogs, hazing was less effective. Citizen-scientists reported improved understanding and acceptance of coyote management tools as well as increased confidence and capacity to deal with human-coyote conflict in their community. For the open space hazing trial, we provided non-personal hazing education using signs, email, and social media as well as staffed education stations in two urban open space parks with highly visible coyotes and prior histories of coyote conflict. Based on self-reported (n=495) results, most park visitors indicated they would haze a coyote in the future and that the educational effort influenced their decision to haze or not
Selective Foraging For Anthropogenic Resources By Black Bears: Minivans In Yosemite National Park
Black bears (Ursus americanus) forage selectively in natural environments. To determine if bears also forage selectively for anthropogenic resources we analyzed data on vehicles broken into by bears from Yosemite National Park, California. We classified vehicles into 9 categories based on their make and model and collected data on use (2001–2007) and availability (2004–2005). From 2001 to 2007 bears broke into 908 vehicles at the following rates: minivan (26.0%), sport–utility vehicle (22.5%), small car (17.1%), sedan (13.7%), truck (11.9%), van (4.2%), sports car (1.7%), coupe (1.7%), and station wagon (1.4%). Only use of minivans (29%) during 2004–2005 was significantly higher than expected (7%). We discuss several competing hypotheses about why bears selected minivans
Dogs Gone Wild: Feral Dog Damage in the United States
Feral dogs have been documented in all 50 states and estimates of damage in the U.S. from these animals amount to \u3e5 million in damage to livestock annually can be attributed to feral dogs. We reviewed national statistics on feral dog damage reported to USDA, APHIS, Wildlife Services for a 10-year period from 1997 through 2006. Damage by feral dogs crossed multiple resource categories (e.g., agriculture, natural resources); some examples of damage include killing and affecting the behavior and habitat use of native wildlife; killing and maiming livestock; and their role as disease vectors to wildlife, domestic animals, and humans. We review the role of dog damage in the U.S., synthesize the amount of damage between resource categories (agriculture, human health and safety, disease, and natural resources), and report trends in dog damage during the 10-year period. Results showed an increase in dog damage across all resource categories indicating the importance of management
Interactions with Humans Shape Coyote Responses to Hazing
Medium and large carnivores coexist with people in urban areas globally, occasionally resulting in negative interactions that prompt questions about how to reduce human-wildlife conflict. Hazing, i.e., scaring wildlife, is frequently promoted as an important non-lethal means for urbanites to reduce conflict but there is limited scientific evidence for its efficacy. We used a population of captive coyotes (Canis latrans) to simulate urban human-coyote interactions and subsequent effects of hazing on coyote behavior. Past experiences with humans significantly affected the number of times a coyote approached a human to necessitate hazing. Coyotes that had been hand fed by adults had to be more frequently hazed than coyotes with other or no past experiences with adults. Past experience with children had no impact on the number of hazing events. The number of times a coyote approached an adult or child was reduced across days based on the accumulative number of times hazed, suggesting coyotes learn to avoid behaviors warranting hazing and that this could be used as a non-lethal management tool. However, prior experience and whether the interaction is with an adult or child can alter the outcomes of hazing and must be considered in determining the efficacy of hazing programs
Individual and population fitness consequences associated with large carnivore use of residential development
Large carnivores are negotiating increasingly developed landscapes, but little is known about how such behavioral plasticity influences their demographic rates and population trends. Some investigators have suggested that the ability of carnivores to behaviorally adapt to human development will enable their persistence, and yet, others have suggested that such landscapes are likely to serve as population sinks or ecological traps. To understand how plasticity in black bear (Ursus americanus) use of residential development influences their population dynamics, we conducted a 6-yr study near Durango, Colorado, USA. Using space-use data on individual bears, we examined the influence of use of residential development on annual measures of bear body fat, cub productivity, cub survival, and adult female survival, after accounting for variation in natural food availability and individual attributes (e.g., age). We then used our field-based vital rate estimates to parameterize a matrix model that simulated asymptotic population growth for bears using residential development to different degrees. We found that bear use of residential development was highly variable within and across years, with bears increasing their foraging within development when natural foods were scarce. Increased bear use of development was associated with increased body fat and cub productivity, but reduced cub and adult survival. When these effects were simultaneously incorporated into a matrix model, we found that the population was projected to decline as bear use of development increased, given that the costs of reduced survival outweighed the benefits of enhanced productivity. Our results provide a mechanistic understanding of how black bear use of residential development exerts opposing effects on different bear fitness traits and a negative effect on population growth, with the magnitude of those effects mediated by variation in environmental conditions. They also highlight the importance of monitoring bear population dynamics, particularly as shifts in bear behavior are likely to drive increases in human-bear conflicts and the perception of growing bear populations. Finally, our work emphasizes the need to consider the demographic viability of large carnivore populations when promoting the coexistence of people and carnivores on shared landscapes
Evaluating Lethal and Nonlethal Management Options for Urban Coyotes
Human-coyote conflict in urban environments is a growing issue in cities throughout the United States with the primary problem being the development of problem individuals that are overly bold and aggressive with people and pets. Little research has focused on management options to deal with this conflict. We better define lethal and nonlethal management strategies associated with proactive and reactive management of coyotes with an emphasis on management of problem individuals. We then provide data from research in the Denver Metropolitan Area (DMA) that focused on reactive lethal removal of problem coyotes and reactive nonlethal hazing (i.e., community-level hazing, a commonly recommended strategy that we better define). The primary lethal management strategy being used in the DMA is to remove problem coyotes only when severe conflict (primarily threats to people) occurs. From 2009-2014 there were 27 removal events (4.5/year) with the average number of coyotes removed per event being 2.1 (range 1 – 11) and the average number of coyotes removed per year being 9.3. The estimated percentage of coyotes removed per year from the population was between 1.0 and 1.8%. We also measured recurrence of conflict (i.e., length of time until another severe conflict occurred in the vicinity of a removal event) as a measure of efficacy. Of the 27 removals, there were nine with recurrence with an average of 245 days (range 30-546) between removals, and 18 events without recurrence and with a mean time since conflict event of 1,042 days (range 133-2,159). For our community-level hazing experiment we used wildlife cameras to record activity of both people and coyotes at four sites (two treatment and two control). At treatment sites with prior history of conflict, we educated and encouraged people to haze visible coyotes and hypothesized that hazing would decrease the activity overlap between people and coyotes on treatment sites. We recorded over 50,000 independent sightings of people and coyotes and found activity overlap between humans and coyotes to be either similar or greater on treatment sites compared to control sites. Our results indicate that reactive nonlethal hazing as conducted in this study was ineffective in reducing human-coyote activity overlap. However, due to a variety of reasons we detail below, we encourage readers to interpret the hazing results with caution. We conclude that reactive lethal removal of problem individuals is an effective means of managing conflict and that proactive nonlethal strategies are critical as well
Economic Consequences of the Wolf Comeback in the Western United States
Gray wolves were eradicated from most of the United States in the 1940’s but have made a comeback in parts of their historic range over the last two decades. First reintroduced into the Greater Yellowstone Ecosystem and central Idaho in the mid-1990’s, wolves have subsequently dispersed into at least 7 western states. Coloradoans became the latest state to take interest in bolstering wolf populations, as residents passed a ballot initiative in November 2020 to reintroduce a self-sustaining population of gray wolves by the end of 2023. Conflicts between people in rural areas that might incur costs (such as livestock loss) and people in urban areas geographically removed from direct contact with wolves suggest that the distribution of benefits may not align uniformly with the distribution of costs. Given that Colorado will imminently make many policy decisions that have an impact on costs and benefits, we review available literature to better understand the magnitude of gainers and losers from wolf reintroduction in western states. Although no single study has included all possible economic values, the magnitude of impacts can be inferred by assembling a broad range of estimates for different types of values into a single space. Our review of existing valuation literature from western states indicates that the magnitude of economic benefits of wolves is many times higher than what it costs to manage wolves and to reduce or compensate for losses to livestock producers and others
A systematic map of human-carnivore coexistence
Carnivore populations globally have largely declined, and coexistence, where humans and carnivores share landscapes, plays a crucial role in carnivore conservation. However, the term “coexistence” is often used in scientific and popular literature without being clearly defined. Herein, we provide a global perspective on what coexistence is and how it is studied. We conducted a systematic map of 366 articles published between 1987 and 2020 to characterize human-carnivore coexistence literature according to coexistence definitions, temporal trends, geographic and taxonomic focus, and four thematic aspects of coexistence: carnivore ecology, human endeavors, social conflict and human-carnivore conflict. We used chi-squared tests and generalized linear models to describe the thematic, taxonomic and geographic focus of the literature. The human-carnivore coexistence literature increased exponentially in the past 30 years, but few articles defined the term “coexistence” and those that did used inconsistent definitions. Thematically, coexistence research showed less emphasis on social conflict, even though it is a major driver of conflict regarding carnivores. The literature also focused primarily on larger carnivores, rather than endangered carnivores, and was primarily led by European and North American authors. We offer a simplified, formal definition of “coexistence” that incorporates the four thematic aspects of coexistence encountered in the literature: Co-occurrence of sustainable carnivore populations and human endeavors with minimal human-carnivore and human-human conflict. We encourage researchers to focus on the social dimensions of coexistence, such as human attitudes towards carnivores or the underlying causes of social conflict, and to broaden the taxonomic and cultural breadth of their projects
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