Exposure to humans and task difficulty levels affect wild raccoons (Procyon lotor) learning

Cognition helps wildlife exploit novel resources and environments. Raccoons (Procyon lotor) have successfully adapted to human presence, in part due to their cognitive abilities. However, interactions between humans and wildlife can create conflict. A better understanding of the raccoon's behavioral flexibility and learning ability could mitigate some conflicts. Our objective was to evaluate wild raccoons learning in contexts varying in terms of exposure to humans (recreational and preservation zoning within protected areas) and task difficulty. Learning can be evaluated over multiple exposures to a cognitive task. Across three years of experiment, we employed 2 food extraction tasks to gauge the change in problem-solving performance over trials. This assessment considered the success probability (the number of successful trials divided by the total number of trials) and the time taken to solve the puzzles. We also looked at the effects of 2 behavioral traits, exploratory diversity and persistence. We found strong evidence for learning over consecutive trials in terms of improved success probability. Improvement in terms of success probability and solving time was more pronounced with the initially easier task. We detected an increase in success probability over trials only in the recreation zones, and there was no evidence of an effect of behavioral traits. The improved performance attributed to learning was also maintained over consecutive years. We provide additional evidence that raccoons can learn how to solve a problem, resulting in a more effective solution in consecutive trials. Finally, we consider the management implications of dealing with raccoons accessing anthropogenic resources.

Diet of the Dingo in Subtropical Australian Forests: Are Small, Threatened Macropods at Risk?

Carnivores fulfil important ecological roles in natural systems yet can also jeopardise the persistence of threatened species. Understanding their diet is, therefore, essential for managing populations of carnivores, as well as those of their prey. This study was designed to better understand the diet of an Australian apex predator, the dingo, and determine whether it poses a threat to at-risk small macropods in two floristically different yet geographically close reserves in subtropical Australia. Based on an analysis of 512 scats, dingo diets comprised 34 different prey taxa, of which 50% were common between reserves. Our findings add support to the paradigm that dingoes are opportunistic and generalist predators that prey primarily on abundant mammalian fauna. Their diets in the Border Ranges were dominated by possum species (frequency of occurrence (FOC) = 92.5%), while their diets in Richmond Range were characterised by a high prevalence of pademelon species (FOC = 46.9%). Medium-sized mammals were the most important dietary items in both reserves and across all seasons. The dietary frequency of medium-sized mammals was generally related to their availability (indexed by camera trapping); however, the avoidance of some species with high availability indicates that prey accessibility may also be important in dictating their dietary choices. Other prey categories were supplementary to diets and varied in importance according to seasonal changes in their availability. The diets included two threatened macropods, the red-legged pademelon and black-striped wallaby. Our availability estimates, together with earlier dietary studies spanning 30 years, suggest that the red-legged pademelon is resilient to the observed predation. The black-striped wallaby occurred in only two dingo scats collected from Richmond Range and was not detected by cameras so the threat to this species could not be determined. Two locally abundant but highly threatened species (the koala and long-nosed potoroo) were not detected in the dingoes' diets, suggesting dingoes do not at present pose a threat to these populations. Our study highlights the importance of site-based assessments, population monitoring and including data on prey availability in dietary investigations.

Both temporal and spatial aspects of predator management influence survival of a temperate ungulate through early life

Recent meta-analyses indicate that predator removal experiments result in marginal increases in prey abundance at best. However, most predator removal studies take place for less than the target prey’s generation time and lack a targeted spatial approach. Our objective was to determine how temporal and spatial aspects of predator control influenced neonate survival of a temperate ungulate. We conducted multiyear coyote (Canis latrans) removals using a crossover experimental design. We found that consecutive years of predator removal increased survival of neonate mule deer (Odocoileus hemionus) more than a single year of removal. We also found that removing coyotes from areas near fawn birth sites increased fawn survival, whereas removing coyotes from areas farther from birth sites did not influence fawn survival. Our results underscore the need for coyote removal programs to (1) employ removal efforts over consecutive years to maximize effectiveness, (2) conduct spatially explicit removal efforts targeting fawning habitat, and (3) occur when the likelihood of additive mortality is high and prey populations have the resources available to grow.

Defining practical and robust study designs for interventions targeted at terrestrial mammalian predators

Conflicts between humans and mammalian predators are globally widespread and increasing, creating a long-lasting challenge for conservation and local livelihoods. Protection interventions, which are essential to conflict mitigation, should be based on solid evidence of effectiveness produced by robust study designs. Yet, it is unclear what study designs have been used in predator-targeted interventions and how they can be improved to provide best practices for replications. I examined how applications of five study designs (before-after, before-after-control-impact, control-impact, crossover [i.e., the same randomly assigned study units acting as treatments and controls during alternating trials], and randomized controlled trial) have changed over time and how these changes are related to authors, predator species, countries, and intervention types (aversion, husbandry, mixed interventions, invasive management, lethal control, and noninvasive management). I applied multinomial regression modeling to 434 cases (28 predator species and 45 countries) from 244 studies published from 1955 to 2020. Study design was related only to intervention type. Less reliable before-after and control-impact studies were the most common (47.7% and 38.2% of cases, respectively), and their use increased over years as did all interventions. The contribution of the most robust before-after-control-impact (7.4%), randomized controlled trial (5.3%), and crossover designs (1.4%) remained minor over time. Crossover is suitable for aversion, most husbandry techniques, and a few other interventions, but crossover interventions also have the most limitations in terms of applicability. Randomized controlled trial is generally applicable, but impractical or inappropriate for some interventions, and before-after-control-impact appears to be the most widely applicable study design for predator-targeted interventions.

Large-Scale Sheep Losses to Wolves (Canis lupus) in Germany Are Related to the Expansion of the Wolf Population but Not to Increasing Wolf Numbers

Recovery of predator populations triggers conflicts due to livestock depredation losses, particularly in Germany where the wolf (Canis lupus) population grows exponentially and livestock (especially sheep) losses raise public concerns and motivate the authorities to control wolf numbers. Yet, the effects of wolf numbers and alternative factors, such as abundance of prey and livestock, on livestock losses in this country are not investigated. In this study, we collected and analyzed data on the numbers of reproductive units of wolves (packs and pairs together) as a surrogate of adult wolf numbers, sheep killed by wolves, living sheep, red deer (Cervus elaphus), roe deer (Capreolus capreolus), and wild boar (Sus scrofa) in every German state and year from 2002 to 2019. We applied a negative binomial Generalized Linear Mixed Model (GLMM) to estimate the effects of these predictors on the numbers of sheep killed by wolves. We also examined the relationships between the percentages of killed/living sheep and the numbers of living sheep. Ranking of 63 models based on the Akaike information criterion revealed that sheep losses were determined by state, year, and number of living sheep, not by wolf numbers, at high precision and accuracy. The number of sheep killed by wolves increased consistently by 41% per year and by 30% for every additional 10,000 sheep, mainly in the north where most wolf territories are concentrated. This means that sheep are protected insufficiently and/or ineffectively. The percentages of killed/living sheep consistently increased by 0.02–0.05% per state and year, with the maximum percentage of 0.7%, on a backdrop of decreasing numbers of living sheep. In conclusion, we demonstrate that sheep losses in Germany have been driven by the expansion of the wolf population, not by wolf numbers, and by the number of sheep available. We suggest that Germany’s wolf conservation policy should focus on alternative non-lethal interventions, enforcement and standardization of intervention monitoring, and promotion of wolf tolerance rather than on lethal control of wolf population size.

Social Repercussion of Translocating a Jaguar in Brazil

The translocation of “problem-animals” is a common non-lethal strategy to deal with human-wildlife conflict. While processes of wildlife translocation have been widely documented, little is known about the social repercussions that take place once the capture and the return of a problem-animal to its natural habitat fail and it has to be permanently placed in captivity. We investigated how the public, an important stakeholder in wildlife conservation, perceived the translocation of a female jaguar to a wildlife captivity center. The objectives were to (1) assess the public's perceptions (e.g., attitudes, emotions, awareness) toward the jaguar and its translocation process, and (2) how these psychological constructs are related. We used the social media profiles of the three institutions involved in the process (one responsible for the jaguar rescues, one that supported its recovery, and the one responsible for the jaguar's final destination) and analyzed the comments left by their followers on posts related to the jaguar and the translocation itself during 25 days. A total of 287 comments were analyzed through coding, a categorizing strategy of qualitative analysis; 33 codes were identified. Results showed high admiration for the work done, positive attitudes and emotions, and concern toward the animal. Lack of awareness about the translocation process was high, with comments of curiosity toward the situation being one of the most commonly found. To a lesser extent, people felt sad for the jaguar not being able to return to the wild and criticized the need for translocation. Admiration for the work had a strong relation with gratitude and broader positive perceptions toward the jaguar's story. Criticism related to concern, which was also related to a need for more information and curiosity. Our findings suggest that the public who engaged with those institutions through their Instagram accounts were grateful for seeing the jaguar safe, but were not aware of the complexity of the operation nor about the nature of the conflict with farmers. The public can either reinforce a particular action or jeopardize an entire operation, depending on their perceptions of the matter. In the case of this jaguar, the public held a positive view; however, we acknowledge the limitations of our sample and recommend further analyses of social repercussions among people who are not followers of these organizations. Furthermore, we recommend engaging other stakeholders to fully understand the human dimensions of translocating this jaguar. Finally, for social acceptance, we highlight the importance of transparency and reliability of the organizations operating the translocation.

Social Effectiveness and Human-Wildlife Conflict: Linking the Ecological Effectiveness and Social Acceptability of Livestock Protection Tools

Human-wildlife interactions are embedded within socio-ecological systems (SES), in which animal behavior and human decision-making reciprocally interact. While a growing body of research addresses specific social and ecological elements of human-wildlife interactions, including conflicts, integrating these approaches is essential for identifying practical and effective solutions. Carnivore predation on livestock can threaten human livelihoods, weaken relationships among stakeholders, and precipitate carnivore declines. As carnivores have received greater protection in recent decades, researchers and managers have sought non-lethal tools to reduce predation and promote coexistence between livestock producers and carnivores. For these tools to be successful, they must effectively deter carnivores, and they must also be adopted by producers. Relatively few studies examine the practical and context-specific effectiveness of non-lethal tools, and even fewer simultaneously consider their social acceptability among producers. To address this gap, we suggest that a tool's ecological effectiveness and social acceptability be analyzed concurrently to determine its social effectiveness. We thus paired an experimental study of a carnivore predation deterrent called Foxlights® with qualitative interviews of livestock producers in Northern California. We placed camera traps in sheep pastures to measure the response of coyotes (Canis latrans) to experimentally deployed Foxlights and interviewed livestock producers before and after the experiment. Our experiment revealed weak evidence for reducing coyote activity with Foxlights, but interviews revealed that the potential adoption of tools had as much to do with their social acceptability and implementation feasibility as with evidence-based measurements of tool effectiveness. Interviewees viewed Foxlights as potentially effective components of husbandry systems, despite the data suggesting otherwise, demonstrating that scientific reductionism may lag behind producer practices of systems-thinking and that isolated demonstrations of a tool's ecological effectiveness do not drive tool adoption. Future empirical tests of non-lethal tools should better consider producers' perspectives and acknowledge that data-based tests of ecological effectiveness alone have a limited place in producer decision-making. Iteratively working with producers can build trust in scientific outputs through the research process itself.

Transitioning towards human-large carnivore coexistence in extensive grazing systems

In light of escalating threats to biodiversity, conflicts between humans and large carnivores in production landscapes must be resolved. We explore how interactions between humans, large carnivores, and livestock can be modified to promote coexistence. We identify four rationales for building coexistence capacities in extensive rangeland livestock production systems: (1) livestock production is a dominant terrestrial land use; (2) large carnivores provide critical contributions to ecological functions; (3) the persecution of large carnivores has high ethical, welfare, reputational and social costs; and (4) a growing body of evidence shows that lethal control can be counterproductive to reducing predation risk. Two key leverage points to foster human-carnivore coexistence are the adoption of preventive non-lethal innovations, and the creation of an enabling environment. Leverage points must be appropriate at the local landscape scale and contribute towards global efforts to conserve large carnivores.

Human-Wildlife Coexistence in Urban Wildlife Management: Insights from Nonlethal Predator Management and Rodenticide Bans

Simple Summary

We seek to understand how U.S. cities manage human coexistence with wild animals that are often disliked, specifically coyotes and rats. To this end, we analyze urban wildlife management plans from around the country that propose to strengthen human–wildlife coexistence. Remarkably, some cities are learning to tolerate and even welcome wild predators, such as coyotes, as long as they do not endanger human safety. Killing aggressive individuals remains a management option of last resort. Alternatively, rats are not tolerated at all, and the use of rodenticides to control rat populations remains widespread. Emerging local restrictions on the use of some rodenticides seek to protect the lives of carnivores who feed on rodents. We discuss what the increased popularity of less lethal forms of urban wildlife management can tell us about the capacity of cities to promote the wellbeing not only of people but of wild animals too.

Abstract

Conceptions of human–wildlife coexistence that acknowledge nonhuman wild animals as fellow urban dwellers with legitimate claims on shared urban spaces are starting to influence urban wildlife management practices. Insofar as at least some wild animals have successfully achieved membership in urban society, how has this revaluation affected how urban wildlife is governed? Our interpretive policy analysis explores this question in two areas of urban wildlife management where practices are becoming less lethal: predator management and rodent control. A directed qualitative content analysis of U.S. urban wildlife management plans and rodent control strategies reveals a shift from conflict to coexistence as the basis for understanding human–wildlife relations in urban settings. Indiscriminate killing of urban wildlife is condemned as unethical as well as impractical, and lethal control figures as a measure of last resort that must be rationally justified. Commensal rodents, however, do not benefit from this shift toward coexistence between humans and nonhuman species. Campaigns to restrict the use of rodenticides are intended to protect carnivores, not the rodents themselves. Though urban wildlife management is consistent with some elements of the vision of multispecies flourishing developed by human–animal studies scholars, not all species benefit equally from this transition, and the legitimacy of wild animals’ claims on shared urban spaces often remains contingent on their good behavior.

Population reduction by hunting helps control human-wildlife conflicts for a species that is a conservation success story

Among the world's large Carnivores, American black bears (Ursus americanus) are the foremost conservation success story. Populations have been expanding across North America because the species is adaptable and tolerant of living near people, and because management agencies in the U.S. and Canada controlled hunting and other human-sources of mortality. As a result, human-black bear conflicts (damage to property, general nuisance, threat to human safety) have dramatically increased in some areas, making it urgently important to develop and deploy a variety of mitigation tools. Previous studies claimed that legal hunting did not directly reduce conflicts, but they did not evaluate whether hunting controlled conflicts via management of population size. Here, we compared temporal patterns of phoned-in complaints about black bears (total ~63,500) in Minnesota, USA, over 4 decades to corresponding bear population estimates: both doubled during the first decade. We also quantified natural bear foods, and found that large year-to-year fluctuations affected numbers of complaints; however, since this variation is due largely to weather, this factor cannot be managed. Complaints fell sharply when the management agency (1) shifted more responsibility for preventing and mitigating conflicts to the public; and (2) increased hunting pressure to reduce the bear population. This population reduction was more extreme than intended, however, and after hunting pressure was curtailed, population regrowth was slower than anticipated; consequently both population size and complaints remained at relatively low levels statewide for 2 decades (although with local hotspots). These long-term data indicated that conflicts can be kept in tolerable bounds by managing population size through hunting; but due to the bluntness of this instrument and deficiencies and uncertainties in monitoring and manipulating populations, it is wiser to maintain a population at a level where conflicts are socially-acceptable than try to reduce it once it is well beyond that point.

Human-wildlife coexistence in a changing world

Human-wildlife conflict (HWC) is a key topic in conservation and agricultural research. Decision makers need evidence-based information to design sustainable management plans and policy instruments. However, providing objective decision support can be challenging because realities and perceptions of human-wildlife interactions vary widely between and within rural, urban, and peri-urban areas. Land users who incur costs through wildlife argue that wildlife-related losses should be compensated and that prevention should be subsidized. Supporters of human-wildlife coexistence policies, such as urban-dwelling people, may not face threats to their livelihoods from wildlife. Such spatial heterogeneity in the cost and benefits of living with wildlife is germane in most contemporary societies. This Special Section features contributions on wildlife-induced damages that range from human perspectives (land use, psychology, governance, local attitudes and perceptions, costs and benefits, and HWC and coexistence theory) to ecological perspectives (animal behavior). Building on current literature and articles in this section, we developed a conceptual model to help frame HWC and coexistence dimensions. The framework can be used to determine damage prevention implementation levels and approaches to HWC resolution. Our synthesis revealed that inter- and transdisciplinary approaches and multilevel governance approaches can help stakeholders and institutions implement sustainable management strategies that promote human-wildlife coexistence.

Culling recolonizing mesopredators increases livestock losses: Evidence from the South African Karoo

Populations of adaptable mesopredators are expanding globally where passive rewilding and natural recolonization are taking place, increasing the risk of conflict with remaining livestock farmers. We analysed data from two social surveys of farmers in the Karoo, South Africa, where black-backed jackals (Canis mesomelas) and caracals (Caracal caracal) have re-emerged as a threat to sheep farms in the context of falling agricultural employment and the expansion of natural areas. We show that irrespective of measurement approach, lethal control of mesopredators in this fragmented socio-economic landscape was associated with increased livestock losses the following year. Terrain ruggedness was positively, and number of farmworkers negatively, associated with livestock losses. Our study provides further evidence that lethal control of mesopredators in this context is probably counter-productive and supports calls to develop, share and financially support a range of non-lethal methods to protect livestock, especially where natural recolonization of mesopredators is occurring. A graphical abstract can be found in Electronic supplementary material.

Selection of new chemicals to be used in conditioned aversion for non-lethal predation control

Globally, native predators and scavengers are threatened through the incidence of illegal poisoning due to increasing human-wildlife conflicts. The use of conditioned taste aversion (CTA) may mitigate such conflicts. CTA is a robust learning paradigm that occurs when animals associate a food with a discomfort induced by a chemical, thereby avoiding that food in subsequent encounters. We reviewed the potential of 167 chemical compounds to be used in CTA, considering effects, margin of safety, accessibility, and detectability. After the review, 15 compounds fulfilled the required characteristics, but only five (thiabendazole, thiram, levamisole, fluconazole and fluralaner) were finally selected to be tested in CTA assays with dogs. Of the tested compounds, thiabendazole, thiram and levamisole caused target food rejection by dogs and reduced the time spent eating during post-conditioning. However, despite being microencapsulated, levamisole appeared to be detectable by dogs, whereas thiram and thiabendazole were not. Fluconazole and fluralaner did not produce any CTA effect. Thiabendazole, thiram and levamisole can therefore induce CTA, and thus are potential candidates as aversive compounds for wildlife management. Thiram is an undetectable, relatively safe and accessible compound that can induce CTA in canids, and opens new possibilities to develop methods of non-lethal predation control.

Tools for co-existence: fladry corrals efficiently repel wild wolves (Canis lupus) from experimental baiting sites

Context Mitigating wolf–livestock conflict is crucial for both wolf (Canis lupus) conservation and livestock farming. Wolf attacks at livestock gathering areas often result in surplus killing, severe economic losses and emotional distress for the farmers, and financial claims from compensation funds. They may also trigger retaliatory killing of wolves. One method for reducing attacks on gathered livestock is the fladry fence, a primary repellent based on wolf neophobia. Fladry, used mainly in North America, remains largely untested in southern Europe. Aims To test the effectiveness of fladry corrals at excluding wild wolves from experimental feeding sites and discuss their potential for protecting livestock in human-dominated landscapes. Methods We tested the repelling efficiency of fladry corrals at six stations baited with livestock remains close to the homesites of three wild-wolf packs in central-northern Greece. Using infrared cameras, we recorded approaching and feeding rates of wolves, brown bears and wild boars attracted to the baits, before and during fladry use. Key results The feeding rate of all wolf packs reduced to zero during fladry use. Effective repelling lasted from 23 to 157 days and ended with the removal of fladry. Wolf approaches also reduced by 75%. Modelling of wolf-approach levels showed fladry effect to be stronger when using a less attractive bait and weaker as pre-baiting duration or wolves’ pre-exposure time to fladry increased. Fladry also significantly reduced the overall feeding rates of wild boars, whereas repellence of brown bears was poor. Key conclusions Fladry can be a cost-effective tool to exclude wolves from small-sized corrals, for weeks or months. It may also be useful for repelling wild boar. We recommend further testing with live-prey at the regional scale with standardised protocols. Implications Fladry installation at farms should take into account livestock attractiveness and wolf habituation. Fladry efficiency and deterrence duration can be improved when it is combined with other livestock protection methods. Wolf habituation to fladry can be reduced by deploying it primarily in high-risk depredation areas. Moreover, deployment soon after an attack could prevent wolves from associating specific farms with being sources of prey.

The parakeet protectors: Understanding opposition to introduced species management

The surveillance and control of introduced and invasive species has become an increasingly important component of environmental management. However, initiatives targeting 'charismatic' wildlife can be controversial. Opposition to management, and the subsequent emergence of social conflict, present significant challenges for would-be managers. Understanding the substance and development of these disputes is therefore vital for improving the legitimacy and effectiveness of wildlife management. It also provides important insights into human-wildlife relations and the 'social dimensions' of wildlife management. Here, we examine how the attempted eradication of small populations of introduced monk parakeets (Myiopsitta monachus) from England has been challenged and delayed by opposition from interested and affected communities. We consider how and why the UK Government's eradication initiative was opposed, focusing on three key themes: disagreements about justifying management, the development of affective attachments between people and parakeets, and the influence of distrustful and antagonistic relationships between proponents and opponents of management. We draw connections between our UK case and previous management disputes, primarily in the USA, and suggest that the resistance encountered in the UK might readily have been foreseen. We conclude by considering how management of this and other introduced species could be made less conflict-prone, and potentially more effective, by reconfiguring management approaches to be more anticipatory, flexible, sensitive, and inclusive.

Rancher-reported efficacy of lethal and non-lethal livestock predation mitigation strategies for a suite of carnivores

Pastoralists have dealt with livestock losses from predators for millennia, yet effective mitigation strategies that balance wildlife conservation and sustainable agriculture are still needed today. In Wyoming, USA, 274 ranchers responded to a retrospective survey, and rated the efficacy of predation mitigation strategies for foxes, dogs, coyotes, wolves, bobcats, mountain lions, bears, and birds (buzzards, eagles, hawks, ravens). Rancher reported efficacy of mitigation varied by predator species, mitigation strategy, and lethality of strategies, but not livestock type. Ranchers perceive they were most effective at mitigating predation by foxes and coyotes, moderately effective at mitigating large carnivores, and the least effective at mitigating birds. Ranchers also reported that avian predators seem to be the most challenging predator type. The general perception was lethal mitigation strategies were more effective than non-lethal strategies, with guard animals showing the most potential among the non-lethal options. In general, ranchers did not perceive non-lethal strategies as a proxy for lethal strategies. However, a few ranchers reported being successful with non-lethal options such as herding, fencing, and stalling at night but more details about such successful applications are needed. Innovation in current or novel non-lethal mitigation strategies, and examples of efficacy, are needed to justify producer adoption.