Integrating sensory ecology and predator-prey theory to understand animal responses to fire.

Fire regimes are changing dramatically worldwide due to climate change, habitat conversion, and the suppression of Indigenous landscape management. Although there has been extensive work on plant responses to fire, including their adaptations to withstand fire and long-term effects of fire on plant communities, less is known about animal responses to fire. Ecologists lack a conceptual framework for understanding behavioural responses to fire, which can hinder wildlife conservation and management. Here, we integrate cue-response sensory ecology and predator-prey theory to predict and explain variation in if, when and how animals react to approaching fire. Inspired by the literature on prey responses to predation risk, this framework considers both fire-naïve and fire-adapted animals and follows three key steps: vigilance, cue detection and response. We draw from theory on vigilance tradeoffs, signal detection, speed-accuracy tradeoffs, fear generalization, neophobia and adaptive dispersal. We discuss how evolutionary history with fire, but also other selective pressures, such as predation risk, should influence animal behavioural responses to fire. We conclude by providing guidance for empiricists and outlining potential conservation applications.

Identifying historical and future global change drivers that place species recovery at risk.

Ecosystem management in the face of global change requires understanding how co-occurring threats affect species and communities. Such an understanding allows for effective management strategies to be identified and implemented. An important component of this is differentiating between factors that are within (e.g. invasive predators) or outside (e.g. drought, large wildfires) of a local manager's control. In the global biodiversity hotspot of south-western Australia, small- and medium-sized mammal species are severely affected by anthropogenic threats and environmental disturbances, including invasive predators, fire, and declining rainfall. However, the relative importance of different drivers has not been quantified. We used data from a long-term monitoring program to fit Bayesian state-space models that estimated spatial and temporal changes in the relative abundance of four threatened mammal species: the woylie (Bettongia penicillata), chuditch (Dasyurus geoffroii), koomal (Trichosurus vulpecula) and quenda (Isoodon fusciventor). We then use Bayesian structural equation modelling to identify the direct and indirect drivers of population changes, and scenario analysis to forecast population responses to future environmental change. We found that habitat loss or conversion and reduced primary productivity (caused by rainfall declines) had greater effects on species' spatial and temporal population change than the range of fire and invasive predator (the red fox Vulpes vulpes) management actions observed in the study area. Scenario analysis revealed that a greater extent of severe fire and further rainfall declines predicted under climate change, operating in concert are likely to further reduce the abundance of these species, but may be mitigated partially by invasive predator control. Considering both historical and future drivers of population change is necessary to identify the factors that risk species recovery. Given that both anthropogenic pressures and environmental disturbances can undermine conservation efforts, managers must consider how the relative benefit of conservation actions will be shaped by ongoing global change.

Combating ecosystem collapse from the tropics to the Antarctic.

Globally, collapse of ecosystems-potentially irreversible change to ecosystem structure, composition and function-imperils biodiversity, human health and well-being. We examine the current state and recent trajectories of 19 ecosystems, spanning 58° of latitude across 7.7 M km2 , from Australia's coral reefs to terrestrial Antarctica. Pressures from global climate change and regional human impacts, occurring as chronic 'presses' and/or acute 'pulses', drive ecosystem collapse. Ecosystem responses to 5-17 pressures were categorised as four collapse profiles-abrupt, smooth, stepped and fluctuating. The manifestation of widespread ecosystem collapse is a stark warning of the necessity to take action. We present a three-step assessment and management framework (3As Pathway Awareness, Anticipation and Action) to aid strategic and effective mitigation to alleviate further degradation to help secure our future.

Carnivore conservation needs evidence-based livestock protection.

Carnivore predation on livestock often leads people to retaliate. Persecution by humans has contributed strongly to global endangerment of carnivores. Preventing livestock losses would help to achieve three goals common to many human societies: preserve nature, protect animal welfare, and safeguard human livelihoods. Between 2016 and 2018, four independent reviews evaluated >40 years of research on lethal and nonlethal interventions for reducing predation on livestock. From 114 studies, we find a striking conclusion: scarce quantitative comparisons of interventions and scarce comparisons against experimental controls preclude strong inference about the effectiveness of methods. For wise investment of public resources in protecting livestock and carnivores, evidence of effectiveness should be a prerequisite to policy making or large-scale funding of any method or, at a minimum, should be measured during implementation. An appropriate evidence base is needed, and we recommend a coalition of scientists and managers be formed to establish and encourage use of consistent standards in future experimental evaluations.

Predator responses to fire: A global systematic review and meta-analysis.

Knowledge of how disturbances such as fire shape habitat structure and composition, and affect animal interactions, is fundamental to ecology and ecosystem management. Predators also exert strong effects on ecological communities, through top-down regulation of prey and competitors, which can result in trophic cascades. Despite their ubiquity, ecological importance and potential to interact with fire, our general understanding of how predators respond to fire remains poor, hampering ecosystem management. To address this important knowledge gap, we conducted a systematic review and meta-analysis of the effects of fire on terrestrial, vertebrate predators world-wide. We found 160 studies spanning 1978-2018. There were 36 studies with sufficient information for meta-analysis, from which we extracted 96 effect sizes (Hedges' g) for 67 predator species relating to changes in abundance indices, occupancy or resource selection in burned and unburned areas, or before and after fire. Studies spanned geographic locations, taxonomic families and study designs, but most were located in North America and Oceania (59% and 24%, respectively), and largely focussed on felids (24%) and canids (25%). Half (50%) of the studies reported responses to wildfire, and nearly one third concerned prescribed (management) fires. There were no clear, general responses of predators to fire, nor relationships with geographic area, biome or life-history traits (e.g. body mass, hunting strategy and diet). Responses varied considerably between species. Analysis of species for which at least three effect sizes had been reported in the literature revealed that red foxes Vulpes vulpes mostly responded positively to fire (e.g. higher abundance in burned compared to unburned areas) and eastern racers Coluber constrictor negatively, with variances overlapping zero only slightly for both species. Our systematic review and meta-analysis revealed strong variation in predator responses to fire, and major geographic and taxonomic knowledge gaps. Varied responses of predator species to fire likely depend on ecosystem context. Consistent reporting of ongoing monitoring and management experiments is required to improve understanding of the mechanisms driving predator responses to fire, and any broader effects (e.g. trophic interactions). The divergent responses of species in our study suggest that adaptive, context-specific management of predator-fire relationships is required.

Mainstreaming human and large carnivore coexistence through institutional collaboration.

Achieving coexistence between large carnivores and humans in human-dominated landscapes (HDLs) is a key challenge for societies globally. This challenge cannot be adequately met with the current sectoral approaches to HDL governance and an academic community largely dominated by disciplinary sectors. Academia (universities and other research institutions and organizations) should take a more active role in embracing societal challenges around conservation of large carnivores in HDLs by facilitating cross-sectoral cooperation to mainstream coexistence of humans and large carnivores. Drawing on lessons from populated regions of Europe, Asia, and South America with substantial densities of large carnivores, we suggest academia should better embrace the principles and methods of sustainability sciences and create institutional spaces for the implementation of transdisciplinary curricula and projects; reflect on research approaches (i.e., disciplinary, interdisciplinary, or transdisciplinary) they apply and how their outcomes could aid leveraging institutional transformations for mainstreaming; and engage with various institutions and stakeholder groups to create novel institutional structures that can respond to multiple challenges of HDL management and human-large carnivore coexistence. Success in mainstreaming this coexistence in HDL will rest on the ability to think and act cooperatively. Such a conservation achievement, if realized, stands to have far-reaching benefits for people and biodiversity.

Incorporación de la Coexistencia entre Humanos y Carnívoros Mayores por Medio de la Colaboración Institucional Resumen Un reto importante para las sociedades mundiales es lograr la coexistencia entre los carnívoros mayores y los humanos en los paisajes dominados por el hombre (HDL, en inglés). Este reto no puede enfrentarse adecuadamente con las actuales estrategias sectoriales que se usan en la gobernanza de los HDL y con una comunidad académica dominada principalmente por sectores disciplinarios. La academia (las universidades y demás instituciones y organizaciones de investigación) debería realizar un papel más activo en la aceptación de los retos sociales que rodean a la conservación de los carnívoros mayores en los HDL al facilitar la cooperación intersectorial para incorporar la coexistencia entre humanos y dichos carnívoros. A partir de las lecciones aprendidas en las regiones pobladas por densidades abundantes de carnívoros mayores en América del Sur, Asia y Europa, sugerimos que la academia debería aceptar de mejor manera los principios y métodos de las ciencia de la sustentabilidad y crear espacios institucionales para la implementación de currículos y proyectos; reflexionar sobre las estrategias de investigación (es decir, disciplinaria, interdisciplinaria o transdisciplinaria) que aplican y cómo sus resultados podrían ayudar en fomentar las transformaciones institucionales para la incorporación; y participar junto a varias instituciones y grupos de accionistas para crear estructuras institucionales novedosas que puedan responder a los múltiples retos del manejo de los HDL y de la coexistencia entre humanos y carnívoros mayores. El éxito en la incorporación de esta coexistencia en los HDL dependerá de la habilidad para pensar y actuar cooperativamente. Tal logro de conservación, si se alcanza, promete tener beneficios de largo alcance para las personas y para la biodiversidad.

Invasive predators and global biodiversity loss.

Invasive species threaten biodiversity globally, and invasive mammalian predators are particularly damaging, having contributed to considerable species decline and extinction. We provide a global metaanalysis of these impacts and reveal their full extent. Invasive predators are implicated in 87 bird, 45 mammal, and 10 reptile species extinctions-58% of these groups' contemporary extinctions worldwide. These figures are likely underestimated because 23 critically endangered species that we assessed are classed as "possibly extinct." Invasive mammalian predators endanger a further 596 species at risk of extinction, with cats, rodents, dogs, and pigs threatening the most species overall. Species most at risk from predators have high evolutionary distinctiveness and inhabit insular environments. Invasive mammalian predators are therefore important drivers of irreversible loss of phylogenetic diversity worldwide. That most impacted species are insular indicates that management of invasive predators on islands should be a global conservation priority. Understanding and mitigating the impact of invasive mammalian predators is essential for reducing the rate of global biodiversity loss.

Managing conflict between large carnivores and livestock.

Large carnivores are persecuted globally because they threaten human industries and livelihoods. How this conflict is managed has consequences for the conservation of large carnivores and biodiversity more broadly. Mitigating human-predator conflict should be evidence-based and accommodate people's values while protecting carnivores. Despite much research into human and large-carnivore coexistence strategies, there have been few attempts to document the success of conflict-mitigation strategies on a global scale. We conducted a meta-analysis of global research on conflict mitigation related to large carnivores and humans. We focused on conflicts that arise from the threat large carnivores pose to livestock. We first used structured and unstructured searching to identify replicated studies that used before-after or control-impact design to measure change in livestock loss as a result of implementing a management intervention. We then extracted relevant data from these studies to calculate an overall effect size for each intervention type. Research effort and focus varied among continents and aligned with the histories and cultures that shaped livestock production and attitudes toward carnivores. Livestock guardian animals most effectively reduced livestock losses. Lethal control was the second most effective control, although its success varied the most, and guardian animals and lethal control did not differ significantly. Financial incentives have promoted tolerance of large carnivores in some settings and reduced retaliatory killings. We suggest coexistence strategies be location-specific, incorporate cultural values and environmental conditions, and be designed such that return on financial investment can be evaluated. Improved monitoring of mitigation measures is urgently required to promote effective evidence-based policy.

Crowdfunding biodiversity conservation.

Raising funds is critical for conserving biodiversity and hence so is scrutinizing emerging financial mechanisms that may help achieve this goal. Anecdotal evidence indicates crowdfunding is being used to support activities needed for biodiversity conservation, yet its magnitude and allocation remain largely unknown. To help address this knowledge gap, we conducted a global analysis based on conservation-focused projects extracted from crowdfunding platforms. For each project, we determined the funds raised, date, country of implementation, proponent characteristics, activity type, biodiversity realm, and target taxa. We identified 72 relevant platforms and 577 conservation-focused projects that raised $4,790,634 since 2009. Although proponents were based in 38 countries, projects were delivered across 80 countries, indicating a potential mechanism of resource mobilization. Proponents were affiliated with nongovernmental organizations (35%) or universities (30%) or were freelancers (26%). Most projects were for research (40%), persuasion (31%), and on-the-ground actions (21%). Projects were more focused on species (57.7%) and terrestrial ecosystems (20.3%), and less focused on marine (8.8%) and freshwater ecosystems (3.6%). Projects focused on 208 species, including a disproportionate number of threatened birds and mammals. Crowdfunding for biodiversity conservation is a global phenomenon and there is potential for expansion, despite possible pitfalls (e.g., uncertainty about effectiveness). Opportunities to advance conservation through crowdfunding arise from its capacity to mobilize funds spatially and increase steadily over time, inclusion of overlooked species, adoption by multiple actors, and funding of activities beyond research. Our findings pave the way for further research on key questions, such as campaign success rates, effectiveness of conservation actions, and drivers of crowdfunding adoption. Even though crowdfunding capital raised has been modest relative to other conservation-finance mechanisms, its contribution goes beyond funding research and providing capital. Embraced with due care, crowdfunding could become an important financial mechanism for biodiversity conservation.