Experimentally testing animal responses to prescribed fire size and severity.

Deserts are often highly biodiverse and provide important habitats for many threatened species. Fire is a dominant disturbance in deserts, and prescribed burning is increasingly being used by conservation managers and Indigenous peoples to mitigate the damaging effects of climate change, invasive plants, and land-use change. The size, severity, and patchiness of fires can affect how animals respond to fire. However, there are almost no studies examining such burn characteristics in desert environments, which precludes the use of such information in conservation planning. Using a before-after control-impact approach with 20 sampling sites, we studied the outcomes of 10 prescribed burns of varying size (5-267 ha), severity, and patchiness to identify which variables best predicted changes in small mammal and reptile species richness and abundance. Three of the 13 species showed a clear response to fire. Captures increased for 2 species (1 mammal, 1 reptile) and decreased for 1 species (a reptile) as the proportional area burned around traps increased. Two other mammal species showed weaker positive responses to fire. Total burn size and burn patchiness were not influential predictors for any species. Changes in capture rates occurred only at sites with the largest and most severe burns. No fire-related changes in capture rates were observed where fires were small and very patchy. Our results suggest that there may be thresholds of fire size or fire severity that trigger responses to fire, which has consequences for management programs underpinned by the patch mosaic burning paradigm. The prescribed burns we studied, which are typical in scale and intensity across many desert regions, facilitated the presence of some taxa and are unlikely to have widespread or persistent negative impacts on small mammal or reptile communities in this ecosystem provided that long unburned habitat harboring threatened species is protected.

Prueba experimental de la respuesta animal al tamaño y gravedad de los incendios controlados Resumen Los desiertos suelen contar con mucha biodiversidad y proporcionar hábitats importantes para una variedad de especies amenazadas. El fuego es una perturbación que domina en los desiertos, y los incendios controlados cada vez se usan más por los gestores de la conservación y los pueblos indígenas para mitigar los efectos dañinos del cambio climático, las plantas invasoras y el cambio de uso de suelo. El tamaño, gravedad y fragmentación de los incendios pueden afectar cómo los animales responden al fuego. Sin embargo, casi no existen estudios que analicen dichas características de la quema en los ambientes desérticos, lo que excluye a dicha información de la planeación de la conservación. Usamos una estrategia de antes­después del control­impacto en 20 sitios de muestreo para estudiar los resultados de diez incendios controlados de diferentes tamaños (5­267 ha), gravedad y fragmentación para identificar cuáles variables pronostican mejor los cambios en la riqueza de especies y abundancia de mamíferos pequeños y reptiles. Tres de las 13 especies mostraron una respuesta clara al incendio. Las capturas incrementaron en dos especies (una de mamífero y una de reptil) y disminuyeron en una especie (un reptil) conforme incrementó el área proporcional incendiada alrededor de las trampas. Otras dos especies de mamíferos mostraron respuestas positivas más débiles ante el fuego. El tamaño total y la fragmentación del incendio no fueron influyentes sobre los pronosticadores de cualquier especie. Los cambios en las tasas de captura ocurrieron solamente en los sitios con los incendios más graves y grandes. No observamos cambios relacionados al incendio en las tasas de captura en donde los incendios fueron pequeños y muy fragmentados. Nuestros resultados sugieren que podría haber umbrales del tamaño o gravedad del incendio que provocan las respuestas al fuego, lo que tiene consecuencias para los programas de manejo sustentados en el paradigma del mosaico de fragmentos del incendio. Los incendios controlados que estudiamos, que son típicos en escala e intensidad en muchas regiones desérticas, facilitaron la presencia de algunos taxones y no tuvieron probabilidad de tener un impacto negativo extenso o persistente sobre las comunidades de mamíferos pequeños y reptiles en este ecosistema, siempre y cuando se proteja el hábitat que lleva mucho tiempo sin incendios y en donde viven las especies amenazadas.

Incorporating citizen science into IUCN Red List assessments.

Many citizen scientists are highly motivated to help address the current extinction crisis. Their work is making valuable contributions to protecting species by raising awareness, identifying species occurrences, assessing population trends, and informing direct management actions, such as captive breeding. However, clear guidance is lacking about how to use existing citizen science data sets and how to design effective citizen science programs that directly inform extinction risk assessments and resulting conservation actions based on the International Union for Conservation of Nature (IUCN) Red List criteria. This may be because of a mismatch between what citizen science can deliver to address extinction risk and the reality of what is needed to inform threatened species listing based on IUCN criteria. To overcome this problem, we examined each IUCN Red List criterion (A-E) relative to the five major types of citizen science outputs relevant to IUCN assessments (occurrence data, presence-absence observations, structured surveys, physical samples, and narratives) to recommend which outputs are most suited to use when applying the IUCN extinction risk assessment process. We explored real-world examples of citizen science projects on amphibians and fungi that have delivered valuable data and knowledge for IUCN assessments. We found that although occurrence data are routinely used in the assessment process, simply adding more observations of occurrence from citizen science information may not be as valuable as inclusion of more nuanced data types, such as presence-absence data or information on threats from structured surveys. We then explored the characteristics of citizen science projects that have already delivered valuable data to support assessments. These projects were led by recognized experts who champion and validate citizen science data, thereby giving greater confidence in its accuracy. We urge increased recognition of the value of citizen science data within the assessment process.

Integración de la ciencia ciudadana a las evaluaciones de la Lista Roja de la UICN Resumen Existe mucha motivación entre los ciudadanos científicos para ayudar a enfrentar la actual crisis de extinción. Sus contribuciones son valiosas para la protección de las especies mediante la concientización, la detección de especies, la evaluación de las tendencias poblacionales y la información sobre acciones directas de gestión, como la cría en cautiverio. Sin embargo, faltan directrices claras sobre cómo utilizar los conjuntos de datos de ciencia ciudadana existentes y cómo diseñar programas de ciencia ciudadana eficaces que informen directamente las evaluaciones del riesgo de extinción y las acciones de conservación resultantes basadas en los criterios de la Lista Roja de la Unión Internacional para la Conservación de la Naturaleza (UICN). Esto puede deberse a un desajuste entre lo que la ciencia ciudadana puede aportar para abordar el riesgo de extinción y la realidad de lo que se necesita para fundamentar la inclusión de especies amenazadas en las listas según los criterios de la UICN. Para superar este obstáculo, analizamos cada criterio de la Lista Roja de la UICN (A­E) en relación a los cinco tipos principales de resultados de la ciencia ciudadana relevantes para las evaluaciones de la UICN (datos de presencia, observaciones de presencia­ausencia, encuestas estructuradas, muestras físicas y narraciones) para recomendar cuáles resultados son los más adecuados para la evaluación del riesgo de extinción de la UICN. Exploramos ejemplos reales de proyectos de ciencia ciudadana sobre anfibios y hongos que han aportado datos y conocimientos valiosos para las evaluaciones de la UICN. Descubrimos que, aunque los datos de presencia se utilizan de forma rutinaria en el proceso de evaluación, la adición de más observaciones de presencia a partir de información de ciencia ciudadana puede no ser tan valioso como la inclusión de tipos de datos más matizados, como datos de presencia­ausencia o información sobre amenazas a partir de encuestas estructuradas. Después analizamos las características de los proyectos de ciencia ciudadana que ya han aportado datos valiosos en apoyo de las evaluaciones. Estos proyectos fueron dirigidos por expertos reconocidos que defienden y validan los datos de la ciencia ciudadana, lo que da mayor confianza en su exactitud. Instamos a un mayor reconocimiento del valor de los datos de la ciencia ciudadana en el proceso de evaluación.

Designing a large-scale track-based monitoring program to detect changes in species distributions in arid Australia.

Monitoring trends in animal populations in arid regions is challenging due to remoteness and low population densities. However, detecting species' tracks or signs is an effective survey technique for monitoring population trends across large spatial and temporal scales. In this study, we developed a simulation framework to evaluate the performance of alternative track-based monitoring designs at detecting change in species distributions in arid Australia. We collated presence-absence records from 550 2-ha track-based plots for 11 vertebrates over 13 years and fitted ensemble species distribution models to predict occupancy in 2018. We simulated plausible changes in species' distributions over the next 15 years and, with estimates of detectability, simulated monitoring to evaluate the statistical power of three alternative monitoring scenarios: (1) where surveys were restricted to existing 2-ha plots, (2) where surveys were optimized to target all species equally, and (3) where surveys were optimized to target two species of conservation concern. Across all monitoring designs and scenarios, we found that power was higher when detecting increasing occupancy trends compared to decreasing trends owing to the relatively low levels of initial occupancy. Our results suggest that surveying 200 of the existing plots annually (with a small subset resurveyed twice within a year) will have at least an 80% chance of detecting 30% declines in occupancy for four of the five invasive species modeled and one of the six native species. This increased to 10 of the 11 species assuming larger (50%) declines. When plots were positioned to target all species equally, power improved slightly for most compared to the existing survey network. When plots were positioned to target two species of conservation concern (crest-tailed mulgara and dusky hopping mouse), power to detect 30% declines increased by 29% and 31% for these species, respectively, at the cost of reduced power for the remaining species. The effect of varying survey frequency depended on its trade-off with the number of sites sampled and requires further consideration. Nonetheless, our research suggests that track-based surveying is an effective and logistically feasible approach to monitoring broad-scale occupancy trends in desert species with both widespread and restricted distributions.

Modeling mammal response to fire based on species' traits.

Fire has shaped ecological communities worldwide for millennia, but impacts of fire on individual species are often poorly understood. We performed a meta-analysis to predict which traits, habitat, or study variables and fire characteristics affect how mammal species respond to fire. We modeled effect sizes of measures of population abundance or occupancy as a function of various combinations of these traits and variables with phylogenetic least squares regression. Nine of 115 modeled species (7.83%) returned statistically significant effect sizes, suggesting most mammals are resilient to fire. The top-ranked model predicted a negative impact of fire on species with lower reproductive rates, regardless of fire type (estimate = -0.68), a positive impact of burrowing in prescribed fires (estimate = 1.46) but not wildfires, and a positive impact of average fire return interval for wildfires (estimate = 0.93) but not prescribed fires. If a species' International Union for Conservation of Nature Red List assessment includes fire as a known or possible threat, the species was predicted to respond negatively to wildfire relative to prescribed fire (estimate = -2.84). These findings provide evidence of experts' abilities to predict whether fire is a threat to a mammal species and the ability of managers to meet the needs of fire-threatened species through prescribed fire. Where empirical data are lacking, our methods provide a basis for predicting mammal responses to fire and thus can guide conservation actions or interventions in species or communities.

Modelos de las respuestas de los mamíferos a los incendios basados en las características de la especie Resumen Durante milenios, los incendios han moldeado a las comunidades ecológicas en todo el mundo y aun así conocemos muy poco sobre el impacto que tienen sobre cada especie. Realizamos un metaanálisis para predecir cuáles características, hábitat o variable de estudio en conjunto con las características del incendio afectan la respuesta de los mamíferos ante este fenómeno. Usamos para modelar los tamaños del efecto de las medidas de la abundancia poblacional o la ocupación como función de varias combinaciones de estas características y variables mediante una regresión filogenética por mínimos cuadrados. Nueve de las 115 especies modeladas (7.83%) devolvieron tamaños del efecto con importancia estadística, lo que sugiere que la mayoría de los mamíferos son resilientes a los incendios. El modelo mejor clasificado pronosticó un impacto negativo de los incendios sobre las especies con tasas reproductivas más bajas, sin importar el tipo de incendio (estimado = -0.68); un impacto positivo de las madrigueras durante las quemas prescritas (estimado = 1.46) pero no durante los incendios forestales; y un impacto positivo del intervalo promedio de rendimiento del incendio para los incendios forestales (estimado = 0.93) pero no para las quemas prescritas. Si la valoración de una especie en la Lista Roja de la Unión Internacional para la Conservación de la Naturaleza incluye a los incendios como una amenaza conocida o posible, pronosticamos que la especie respondería negativamente a los incendios forestales con relación a la quema prescrita (estimado = -2.84). Estos hallazgos proporcionan evidencia de la habilidad que tienen los expertos para predecir si los incendios son una amenaza para los mamíferos y la habilidad de los gestores para cumplir con las necesidades de las especies amenazadas por incendios por medio de las quemas prescritas. En caso de que falte información empírica, nuestros métodos proporcionan una base para predecir las respuestas de los mamíferos a los incendios y así orientar a las acciones o intervenciones de conservación para una especie o comunidad.

Right-way fire in Australia's spinifex deserts: An approach for measuring management success when fire activity varies substantially through space and time.

Indigenous Australians used fire in spinifex deserts for millennia. These practices mostly ceased following European colonisation, but many contemporary Indigenous groups seek to restore 'right-way fire' practices, to meet inter-related social, economic, cultural and biodiversity objectives. However, measuring and reporting on the fire pattern outcomes of management is challenging, because the spatio-temporal patterns of right-way fire are not clearly defined, and because spatio-temporal variability in rainfall makes fire occurrence highly variable in these desert environments. We present an approach for measuring and reporting on fire management outcomes to account for spatio-temporal rainfall variability. The purpose is to support Indigenous groups to assess performance against their management targets, and lay the groundwork for developing an accredited method for valuing combined social, cultural and biodiversity outcomes. We reviewed fire management plans of desert Indigenous groups to identify spatial fire pattern indicators for right-way fire in spinifex deserts. We integrated annual rainfall surfaces with time-since fire mapping (using Landsat imagery) to create a new spatial dataset of accumulated rainfall-since-last-fire, that better represents post-fire vegetation recovery as categorised by local Indigenous people. The fire pattern indicators were merged into a single score using an environmental accounting approach. To strengthen interpretation, we developed an approach for identifying a control area with matching vegetation and fire history, up to the point of management. We applied these methods to a 125,000 ha case study area: Durba Hills, managed by the Martu people of Western Australia. Using a 20-year time series, we show that since right-way fire management at Durba Hills was re-introduced (2009), the fire pattern indicators have improved compared to those in the matched control area, and the composite result is closer to the fine-scaled mosaic of right-way fire pattern targets. Our approach could be used by Indigenous groups to track performance, and inform annual fire management planning. As the indicators are standardised for rainfall variation, results from multiple sites can be aggregated to track changes in performance at larger scales. Finally, our approach could be adapted for other fire-prone areas, both in Australia and internationally with high spatio-temporal rainfall variability, to improve management planning and evaluation.

Animal mortality during fire.

Earth's rapidly warming climate is propelling us towards an increasingly fire-prone future. Currently, knowledge of the extent and characteristics of animal mortality rates during fire remains rudimentary, hindering our ability to predict how animal populations may be impacted in the future. To address this knowledge gap, we conducted a global systematic review of the direct effects of fire on animal mortality rates, based on studies that unequivocally determined the fate of animals during fire. From 31 studies spanning 1984-2020, we extracted data on the direct impacts of fire on the mortality of 31 species from 23 families. From these studies, there were 43 instances where direct effects were measured by reporting animal survival from pre- to post-fire. Most studies were conducted in North America (52%) and Oceania (42%), focused largely on mammals (53%) and reptiles (30%), and reported mostly on animal survival in planned (82%) and/or low severity (70%) fires. We found no studies from Asia, Europe or South America. Although there were insufficient data to conduct a formal meta-analysis, we tested the effect of fire type, fire severity, fire regime, animal body mass, ecological attributes and class on survival. Only fire severity affected animal mortality, with a higher proportion of animals being killed by high than low severity fires. Recent catastrophic fires across the globe have drawn attention to the plight of animals exposed to wildfire. Yet, our systematic review suggests that a relatively low proportion of animals (mean predicted mortality [95% CI] = 3% [1%-9%]) are killed during fire. However, our review also underscores how little we currently know about the direct effects of fire on animal mortality, and highlights the critical need to understand the effects of high severity fire on animal populations.

Eight things you should never do in a monitoring program: an Australian perspective.

Monitoring is critical to gauge the effect of environmental management interventions as well as to measure the effects of human disturbances such as climate change. Recognition of the critical need for monitoring means that, at irregular intervals, recommendations are made for new government-instigated programs or to revamp existing ones. Using insights from past well-intentioned (but sadly also often failed) attempts to establish and maintain government-instigated monitoring programs in Australia, we outline eight things that should never be done in environmental monitoring programs (if they aim to be useful). These are the following: (1) Never commence a new environmental management initiative without also committing to a monitoring program. (2) Never start a monitoring program without clear questions. (3) Never implement a monitoring program without first doing a proper experimental design. (4) Never ignore the importance of matching the purpose and objectives of a monitoring program to the design of that program. (5) Never change the way you monitor something without ensuring new methods can be calibrated with the old ones. (6) Never try to monitor everything. (7) Never collect data without planning to curate and report on it. (8) If possible, avoid starting a monitoring program without the necessary resources secured. To balance our "nevers", we provide a checklist of actions that will increase the chances a monitoring program will actually measure the effectiveness of environmental management. Scientists and resource management practitioners need to be part of a stronger narrative for, and key participants in, well-designed, implemented, and maintained government-led monitoring programs. We argue that monitoring programs should be mandated in threatened species conservation programs and all new environmental management initiatives.

A checklist of attributes for effective monitoring of threatened species and threatened ecosystems.

Monitoring of threatened species and threatened ecosystems is critical for determining population trends, identifying urgency of management responses, and assessing the efficacy of management interventions. Yet many threatened species and threatened ecosystems are not monitored and for those that are, the quality of the monitoring is often poor. Here we provide a checklist of factors that need to be considered for inclusion in robust monitoring programs for threatened species and threatened ecosystems. These factors can be grouped under four broad themes - the design of monitoring programs, the structure and governance of monitoring programs, data management and reporting, and appropriate funding and legislative support. We briefly discuss key attributes of our checklist under these themes. Key topics in our first theme of the design of monitoring programs include appropriate objective setting, identification of the most appropriate entities to be measured, consistency in methodology and protocols through time, ensuring monitoring is long-term, and embedding monitoring into management. Under our second theme which focuses on the structure and governance of monitoring programs for threatened species and ecosystems, we touch on the importance of adopting monitoring programs that: test the effectiveness of management interventions, produce results that are relevant to management, and engage with (and are accepted by) the community. Under Theme 3, we discuss why data management is critical and highlight that the costs of data curation, analysis and reporting need to be factored into budgets for monitoring programs. This requires that appropriate levels of funding are made available for monitoring programs, beyond just the cost of data collection - a key topic examined in Theme 4. We provide examples, often from Australia, to highlight the importance of each of the four themes. We recognize that these themes and topics in our checklist are often closely inter-related and therefore provide a conceptual model highlighting these linkages. We suggest that our checklist can help identify the parts of existing monitoring programs for threatened species and threatened ecosystems that are adequate for the purpose or may be deficient and need to be improved.

Deconstructing compassionate conservation.

Compassionate conservation focuses on 4 tenets: first, do no harm; individuals matter; inclusivity of individual animals; and peaceful coexistence between humans and animals. Recently, compassionate conservation has been promoted as an alternative to conventional conservation philosophy. We believe examples presented by compassionate conservationists are deliberately or arbitrarily chosen to focus on mammals; inherently not compassionate; and offer ineffective conservation solutions. Compassionate conservation arbitrarily focuses on charismatic species, notably large predators and megaherbivores. The philosophy is not compassionate when it leaves invasive predators in the environment to cause harm to vastly more individuals of native species or uses the fear of harm by apex predators to terrorize mesopredators. Hindering the control of exotic species (megafauna, predators) in situ will not improve the conservation condition of the majority of biodiversity. The positions taken by so-called compassionate conservationists on particular species and on conservation actions could be extended to hinder other forms of conservation, including translocations, conservation fencing, and fertility control. Animal welfare is incredibly important to conservation, but ironically compassionate conservation does not offer the best welfare outcomes to animals and is often ineffective in achieving conservation goals. Consequently, compassionate conservation may threaten public and governmental support for conservation because of the limited understanding of conservation problems by the general public.

Deconstrucción de la Conservación Compasiva Resumen La conservación compasiva se enfoca en cuatro principios: no causar daño; los individuos importan; la integración de los animales individualmente; y la coexistencia pacífica entre los humanos u los animales. Recientemente, la conservación compasiva ha sido promovida como una alternativa a la filosofía convencional de la conservación. Creemos que los ejemplos presentados por los conservacionistas compasivos han sido elegidos arbitraria o deliberadamente por estar enfocados en los mamíferos; por ser inherentes y no compasivos; y por ofrecer soluciones de conservación poco efectivas. La conservación compasiva se enfoca arbitrariamente en las especies carismáticas, principalmente los grandes depredadores y los megaherbívoros. La filosofía no es compasiva cuando deja que los depredadores invasores dentro del ambiente causen daño a un vasto número de individuos nativos o usa el miedo al daño por superdepredadores para aterrorizar a los mesodepredadores. El entorpecimiento del control de especies exóticas (megafauna, depredadores) in situ no mejorará las condiciones de conservación de la mayoría de la biodiversidad, incluso si los conservacionistas compasivos no dañan a los individuos exóticos. Las posiciones que toman los llamados conservacionistas compasivos sobre especies particulares y sobre las acciones de conservación podrían extenderse para entorpecer otros tipos de conservación, incluyendo las reubicaciones, el encercado para la conservación y el control de la fertilidad. El bienestar animal es increíblemente importante para la conservación e irónicamente, la conservación compasiva no ofrece los mejores resultados de bienestar para los animales y comúnmente es poco efectiva en el logro de los objetivos de conservación. Como consecuencia, la conservación compasiva puede poner en peligro el apoyo público y del gobierno que tiene la conservación debido al entendimiento poco limitado que tiene el público general sobre los problemas de conservación.

The contribution of policy, law, management, research, and advocacy failings to the recent extinctions of three Australian vertebrate species.

Extinctions typically have ecological drivers, such as habitat loss. However, extinction events are also influenced by policy and management settings that may be antithetical to biodiversity conservation, inadequate to prevent extinction, insufficiently resourced, or poorly implemented. Three endemic Australian vertebrate species-the Christmas Island pipistrelle (Pipistrellus murrayi), Bramble Cay melomys (Melomys rubicola), and Christmas Island forest skink (Emoia nativitatis)-became extinct from 2009 to 2014. All 3 extinctions were predictable and probably preventable. We sought to identify the policy, management, research, and other shortcomings that contributed to their extinctions or failed to prevent them. These included a lack within national environmental legislation and policy of explicit commitment to the prevention of avoidable extinctions, lack of explicit accountability, inadequate resources for conservation (particularly for species not considered charismatic or not of high taxonomic distinctiveness), inadequate biosecurity, a slow and inadequate process for listing species as threatened, recovery planning that failed to consider the need for emergency response, inability of researchers to identify major threatening factors, lack of public engagement and involvement in conservation decisions, and limited advocacy. From these 3 cases, we recommend: environmental policy explicitly seeks to prevent extinction of any species and provides a clear chain of accountability and an explicit requirement for public inquiry following any extinction; implementation of a timely and comprehensive process for listing species as threatened and for recovery planning; reservation alone not be assumed sufficient to maintain species; enhancement of biosecurity measures; allocation of sufficient resources to undertake actions necessary to prevent extinction; monitoring be considered a pivotal component of the conservation response; research provides timely identification of factors responsible for decline and of the risk of extinction; effective dissemination of research results; advocacy by an informed public for the recovery of threatened species; and public involvement in governance of the recovery process. These recommendations should be applicable broadly to reduce the likelihood and incidence of extinctions.

Loss of terrestrial biodiversity in Australia: Magnitude, causation, and response.

Australia's biota is species rich, with high rates of endemism. This natural legacy has rapidly diminished since European colonization. The impacts of invasive species, habitat loss, altered fire regimes, and changed water flows are now compounded by climate change, particularly through extreme drought, heat, wildfire, and flooding. Extinction rates, already far exceeding the global average for mammals, are predicted to escalate across all taxa, and ecosystems are collapsing. These losses are symptomatic of shortcomings in resourcing, law, policy, and management. Informed by examples of advances in conservation practice from invasive species control, Indigenous land management, and citizen science, we describe interventions needed to enhance future resilience. Many characteristics of Australian biodiversity loss are globally relevant, with recovery requiring society to reframe its relationship with the environment.

Fire as a driver and mediator of predator-prey interactions.

Both fire and predators have strong influences on the population dynamics and behaviour of animals, and the effects of predators may either be strengthened or weakened by fire. However, knowledge of how fire drives or mediates predator-prey interactions is fragmented and has not been synthesised. Here, we review and synthesise knowledge of how fire influences predator and prey behaviour and interactions. We develop a conceptual model based on predator-prey theory and empirical examples to address four key questions: (i) how and why do predators respond to fire; (ii) how and why does prey vulnerability change post-fire; (iii) what mechanisms do prey use to reduce predation risk post-fire; and (iv) what are the outcomes of predator-fire interactions for prey populations? We then discuss these findings in the context of wildlife conservation and ecosystem management before outlining priorities for future research. Fire-induced changes in vegetation structure, resource availability, and animal behaviour influence predator-prey encounter rates, the amount of time prey are vulnerable during an encounter, and the conditional probability of prey death given an encounter. How a predator responds to fire depends on fire characteristics (e.g. season, severity), their hunting behaviour (ambush or pursuit predator), movement behaviour, territoriality, and intra-guild dynamics. Prey species that rely on habitat structure for avoiding predation often experience increased predation rates and lower survival in recently burnt areas. By contrast, some prey species benefit from the opening up of habitat after fire because it makes it easier to detect predators and to modify their behaviour appropriately. Reduced prey body condition after fire can increase predation risk either through impaired ability to escape predators, or increased need to forage in risky areas due to being energetically stressed. To reduce risk of predation in the post-fire environment, prey may change their habitat use, increase sheltering behaviour, change their movement behaviour, or use camouflage through cryptic colouring and background matching. Field experiments and population viability modelling show instances where fire either amplifies or does not amplify the impacts of predators on prey populations, and vice versa. In some instances, intense and sustained post-fire predation may lead to local extinctions of prey populations. Human disruption of fire regimes is impacting faunal communities, with consequences for predator and prey behaviour and population dynamics. Key areas for future research include: capturing data continuously before, during and after fires; teasing out the relative importance of changes in visibility and shelter availability in different contexts; documenting changes in acoustic and olfactory cues for both predators and prey; addressing taxonomic and geographic biases in the literature; and predicting and testing how changes in fire-regime characteristics reshape predator-prey interactions. Understanding and managing the consequences for predator-prey communities will be critical for effective ecosystem management and species conservation in this era of global change.

After the Megafires: What Next for Australian Wildlife?

The 2019-2020 megafires in Australia brought a tragic loss of human life and the most dramatic loss of habitat for threatened species and devastation of ecological communities in postcolonial history. What must be done now to keep impacted species from extinction? What can be done to avoid a repeat of the impacts of such devastating bushfires? Here, we describe hard-won lessons that may also be of global relevance.

Assessing Risks to Wildlife from Free-Roaming Hybrid Cats: The Proposed Introduction of Pet Savannah Cats to Australia as a Case Study.

Hybrid cats-created by crossing different species within the family Felidae-are popular pets, but they could potentially threaten native species if they escape and establish free-roaming populations. To forestall this possibility, the Australian government imposed a specific ban on importation of the savannah cat, a hybrid created by crossing the domestic cat Felis catus and serval Leptailurus serval, in 2008. We develop a decision-framework that identifies those species of non-volant native mammals in Australia that would likely have been susceptible to predation by savannah cats if importation and establishment had occurred. We assumed that savannah cats would hunt ecologically similar prey to those that are depredated by both the domestic cat and the serval, and categorised native mammals as having different levels of susceptibility to predation by savannah cats based on their size, habitat range, and behaviour. Using this framework, we assessed savannah cats as likely to add at least 28 extant native mammal species to the 168 that are known already to be susceptible to predation by the domestic cat, posing a risk to 91% of Australia's extant non-volant terrestrial mammal species (n = 216) and to 93% of threatened mammal species. The framework could be generalised to assess risks from any other hybrid taxa.

Corrigendum to: Condition index monitoring supports conservation priorities for the protection of threatened grass-finch populations.

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Extraterritorial hunting expeditions to intense fire scars by feral cats.

Feral cats are normally territorial in Australia's tropical savannahs, and hunt intensively with home-ranges only two to three kilometres across. Here we report that they also undertake expeditions of up to 12.5 km from their home ranges to hunt for short periods over recently burned areas. Cats are especially likely to travel to areas burned at high intensity, probably in response to vulnerability of prey soon after such fires. The movements of journeying cats are highly directed to specific destinations. We argue that the effect of this behaviour is to increase the aggregate impact of cats on vulnerable prey. This has profound implications for conservation, considering the ubiquity of feral cats and global trends of intensified fire regimes.

Occupancy of the Invasive Feral Cat Varies with Habitat Complexity.

The domestic cat (Felis catus) is an invasive exotic in many locations around the world and is thought to be a key factor driving recent mammal declines across northern Australia. Many mammal species native to this region now persist only in areas with high topographic complexity, provided by features such as gorges or escarpments. Do mammals persist in these habitats because cats occupy them less, or despite high cat occupancy? We show that occupancy of feral cats was lower in mammal-rich habitats of high topographic complexity. These results support the idea that predation pressure by feral cats is a factor contributing to the collapse of mammal communities across northern Australia. Managing impacts of feral cats is a global conservation challenge. Conservation actions such as choosing sites for small mammal reintroductions may be more successful if variation in cat occupancy with landscape features is taken into account.

Three Molecular Markers Show No Evidence of Population Genetic Structure in the Gouldian Finch (Erythrura gouldiae).

Assessment of genetic diversity and connectivity between regions can inform conservation managers about risk of inbreeding, potential for adaptation and where population boundaries lie. The Gouldian finch (Erythrura gouldiae) is a threatened species in northern Australia, occupying the savannah woodlands of the biogeographically complex monsoon tropics. We present the most comprehensive population genetic analysis of diversity and structure the Gouldian finch using 16 microsatellite markers, mitochondrial control region and 3,389 SNPs from genotyping-by-sequencing. Mitochondrial diversity is compared across three related, co-distributed finches with different conservation threat-statuses. There was no evidence of genetic differentiation across the western part of the range in any of the molecular markers, and haplotype diversity but not richness was lower than a common co-distributed species. Individuals within the panmictic population in the west may be highly dispersive within this wide area, and we urge caution when interpreting anecdotal observations of changes to the distribution and/or flock sizes of Gouldian finch populations as evidence of overall changes to the population size of this species.

Body Condition Indices Predict Reproductive Success but Not Survival in a Sedentary, Tropical Bird.

Body condition may predict individual fitness because those in better condition have more resources to allocate towards improving their fitness. However, the hypothesis that condition indices are meaningful proxies for fitness has been questioned. Here, we ask if intraspecific variation in condition indices predicts annual reproductive success and survival. We monitored a population of Neochmia phaeton (crimson finch), a sedentary, tropical passerine, for reproductive success and survival over four breeding seasons, and sampled them for commonly used condition indices: mass adjusted for body size, muscle and fat scores, packed cell volume, hemoglobin concentration, total plasma protein, and heterophil to lymphocyte ratio. Our study population is well suited for this research because individuals forage in common areas and do not hold territories such that variation in condition between individuals is not confounded by differences in habitat quality. Furthermore, we controlled for factors that are known to impact condition indices in our study population (e.g., breeding stage) such that we assessed individual condition relative to others in the same context. Condition indices that reflect energy reserves predicted both the probability of an individual fledging young and the number of young produced that survived to independence, but only during some years. Those that were relatively heavy for their body size produced about three times more independent young compared to light individuals. That energy reserves are a meaningful predictor of reproductive success in a sedentary passerine supports the idea that energy reserves are at least sometimes predictors of fitness. However, hematological indices failed to predict reproductive success and none of the indices predicted survival. Therefore, some but not all condition indices may be informative, but because we found that most indices did not predict any component of fitness, we question the ubiquitous interpretation of condition indices as surrogates for individual quality and fitness.

Feral Cats Are Better Killers in Open Habitats, Revealed by Animal-Borne Video.

One of the key gaps in understanding the impacts of predation by small mammalian predators on prey is how habitat structure affects the hunting success of small predators, such as feral cats. These effects are poorly understood due to the difficulty of observing actual hunting behaviours. We attached collar-mounted video cameras to feral cats living in a tropical savanna environment in northern Australia, and measured variation in hunting success among different microhabitats (open areas, dense grass and complex rocks). From 89 hours of footage, we recorded 101 hunting events, of which 32 were successful. Of these kills, 28% were not eaten. Hunting success was highly dependent on microhabitat structure surrounding prey, increasing from 17% in habitats with dense grass or complex rocks to 70% in open areas. This research shows that habitat structure has a profound influence on the impacts of small predators on their prey. This has broad implications for management of vegetation and disturbance processes (like fire and grazing) in areas where feral cats threaten native fauna. Maintaining complex vegetation cover can reduce predation rates of small prey species from feral cat predation.