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The Komodo dragon (Varanus komodoensis) is an endangered, island‐endemic species with a naturally restricted distribution. Despite this, no previous studies have attempted to predict the effects of climate change on this iconic species. We used extensive Komodo dragon monitoring data, climate, and sea‐level change projections to build spatially explicit demographic models for the Komodo dragon. These models project the species’ future range and abundance under multiple climate change scenarios. We ran over one million model simulations with varying model parameters, enabling us to incorporate uncertainty introduced from three main sources: (a) structure of global climate models, (b) choice of greenhouse gas emission trajectories, and (c) estimates of Komodo dragon demographic parameters. Our models predict a reduction in range‐wide Komodo dragon habitat of 8%–87% by 2050, leading to a decrease in habitat patch occupancy of 25%–97% and declines of 27%–99% in abundance across the species' range. We show that the risk of extirpation on the two largest protected islands in Komodo National Park (Rinca and Komodo) was lower than other island populations, providing important safe havens for Komodo dragons under global warming. Given the severity and rate of the predicted changes to Komodo dragon habitat patch occupancy (a proxy for area of occupancy) and abundance, urgent conservation actions are required to avoid risk of extinction. These should, as a priority, be focused on managing habitat on the islands of Komodo and Rinca, reflecting these islands’ status as important refuges for the species in a warming world. Variability in our model projections highlights the importance of accounting for uncertainties in demographic and environmental parameters, structural assumptions of global climate models, and greenhouse gas emission scenarios when simulating species metapopulation dynamics under climate change., The Komodo dragon (Varanus komodoensis) is an endangered, island‐endemic species with a naturally restricted distribution. Despite this, no previous studies have attempted to predict the effects of climate change on this iconic species. Our modeling shows that without quick action to mitigate climate change impacts on Komodo National Park and on the island of Flores, we risk committing Komodo dragons—a globally iconic species—to extinction.

Knowledge of global patterns of biodiversity, ranging from intraspecific genetic diversity (GD) to taxonomic and phylogenetic diversity, is essential for identifying and conserving the processes that shape the distribution of life. Yet, global patterns of GD and its drivers remain elusive. Here we assess existing biodiversity theories to explain and predict the global distribution of GD in terrestrial mammal assemblages. We find a strong positive covariation between GD and interspecific diversity, with evolutionary time, reflected in phylogenetic diversity, being the best predictor of GD. Moreover, we reveal the negative effect of past rapid climate change and the positive effect of inter-annual precipitation variability in shaping GD. Our models, explaining almost half of the variation in GD globally, uncover the importance of deep evolutionary history and past climate stability in accumulating and maintaining intraspecific diversity, and constitute a crucial step towards reducing the Wallacean shortfall for an important dimension of biodiversity., The drivers of genetic diversity (GD) are poorly understood at the global scale. Here the authors show, for terrestrial mammals, that within-species GD covaries with phylogenetic diversity and is higher in locations with more stable past climates. They also interpolate GD for data-poor locations such as the tropics.

Pathways to extinction start long before the death of the last individual. However, causes of early stage population declines and the susceptibility of small residual populations to extirpation are typically studied in isolation. Using validated process-explicit models, we disentangle the ecological mechanisms and threats that were integral in the initial decline and later extinction of the woolly mammoth. We show that reconciling ancient DNA data on woolly mammoth population decline with fossil evidence of location and timing of extinction requires process-explicit models with specific demographic and niche constraints, and a constrained synergy of climatic change and human impacts. Validated models needed humans to hasten climate-driven population declines by many millennia, and to allow woolly mammoths to persist in mainland Arctic refugia until the mid-Holocene. Our results show that the role of humans in the extinction dynamics of woolly mammoth began well before the Holocene, exerting lasting effects on the spatial pattern and timing of its range-wide extinction.

Predation by cats (Felis catus) is implicated in the decline and extinction of many Australian mammal species. We estimate the number of mammals killed by cats across Australia through meta-analysis of data on the frequency of mammals in cat diet samples from 107 studies. For feral cats in largely natural landscapes, the spatially-weighted mean frequency of mammals in diet samples was 70% (44% for native species, 34% for introduced species). Frequency was significantly higher on the mainland, and in areas of low temperature and topographic ruggedness. Geographic patterns varied markedly between native and introduced mammals, with native mammals most frequent in northern Australia. We estimate that: (i) 815 million individuals yr-1 are killed by feral cats in natural landscapes, 56% of which are native species; (ii) 149 million individuals yr-1 are killed by unowned cats in highly modified landscapes; and (iii) 180 million individuals yr-1 are killed by pet cats. For the latter two components, mainly introduced species are killed. Collectively, across the three components of the cat population, 1,144 million individuals yr-1 are killed by cats, of which, at least 40% (459 million individuals yr-1) are native species. It remains challenging to interpret this tally in terms of its impact on population viability for Australian mammals, because demographic information is not available for most species. However, our estimate of annual mammal mortality due to cat predation is substantially higher than that due to another key threatening process, land clearing.

Using the past to inform the future The late Quaternary paleorecord, within the past ∼130,000 years, can help to inform present-day management of the Earth's ecosystems and biota under climate change. Fordham et al. review when and where rapid climate transitions can be found in the paleoclimate record. They show how such events in Earth's history can shape our understanding of the consequences of future global warming, including rates of biodiversity loss, changes in ecosystem structure and function, and degradation in the goods and services that these ecosystems provide to humanity. They also highlight how recent developments at the intersection of paleoecology, paleoclimatology, and macroecology can provide opportunities to anticipate and manage the responses of species and ecosystems to changing climates in the Anthropocene. Science , this issue p. eabc5654

The European rabbit (Oryctolagus cuniculus) is a notorious economic and environmental pest species in its invasive range. To better understand the population and range dynamics of this species, 41 yr of abundance data have been collected from 116 unique sites across a broad range of climatic and environmental conditions in Australia. We analyzed this time series of abundance data to determine whether interannual variation in climatic conditions can be used to map historic, contemporary, and potential future fluctuations in rabbit abundance from regional to continental scales. We constructed a hierarchical Bayesian regression model of relative abundance that corrected for observation error and seasonal biases. The corrected abundances were regressed against environmental and disease variables in order to project high spatiotemporal resolution, continent-wide rabbit abundances. We show that rabbit abundance in Australia is highly variable in space and time, being driven primarily by internnual variation in temperature and precipitation in concert with the prevalence of a non-pathogenic virus. Moreover, we show that internnual variation in local spatial abundances can be mapped effectively at a continental scale using highly resolved spatiotemporal predictors, allowing "hot spots" of persistently high rabbit abundance to be identified. Importantly, cross-validated model performance was fair to excellent within and across distinct climate zones. Long-term monitoring data for invasive species can be used to map fine-scale spatiotemporal fluctuations in abundance patterns when accurately accounting for inherent sampling biases. Our analysis provides ecologists and pest managers with a clearer understanding of the determinants of rabbit abundance in Australia, offering an important new approach for predicting spatial abundance patterns of invasive species at the near-term temporal scales that are directly relevant to resource management.

Criticism has been levelled at climate-change-induced forecasts of species range shifts that do not account explicitly for complex population dynamics. The relative importance of such dynamics under climate change is, however, undetermined because direct tests comparing the performance of demographic models vs. simpler ecological niche models are still lacking owing to difficulties in evaluating forecasts using real-world data. We provide the first comparison of the skill of coupled ecological-niche-population models and ecological niche models in predicting documented shifts in the ranges of 20 British breeding bird species across a 40-year period. Forecasts from models calibrated with data centred on 1970 were evaluated using data centred on 2010. We found that more complex coupled ecological-niche-population models (that account for dispersal and metapopulation dynamics) tend to have higher predictive accuracy in forecasting species range shifts than structurally simpler models that only account for variation in climate. However, these better forecasts are achieved only if ecological responses to climate change are simulated without static snapshots of historic land use, taken at a single point in time. In contrast, including both static land use and dynamic climate variables in simpler ecological niche models improve forecasts of observed range shifts. Despite being less skilful at predicting range changes at the grid-cell level, ecological niche models do as well, or better, than more complex models at predicting the magnitude of relative change in range size. Therefore, ecological niche models can provide a reasonable first approximation of the magnitude of species' potential range shifts, especially when more detailed data are lacking on dispersal dynamics, demographic processes underpinning population performance, and change in land cover., The Australian Research Council supported D.A.F, C.B. and B.W.B (FT140101192, DP1096427, FT100100200, respectively). M.B.A and D.N. acknowledge support from the Foundation for Science and Technology (PTDC/AAG‐MAA/3764/2014).

The current distribution of species, environmental conditions and their interactions represent only one snapshot of a planet that is continuously changing, in part due to human influences. To distinguish human impacts from natural factors, the magnitude and pace of climate shifts since the Last Glacial Maximum are often used to determine whether patterns of diversity today are artefacts of past climate change. In the absence of high-temporal-resolution paleoclimate reconstructions, this is generally done by assuming that past climate change occurred at a linear pace between widely spaced (usually, ≥ 1,000 years) climate snapshots. We show here that this is a flawed assumption, because regional climates have changed significantly across decades and centuries during glacial/interglacial cycles, likely causing rapid regional replacement of biota. We demonstrate how recent atmosphere-ocean general circulation model (AOGCM) simulations of the climate of the past 21,000 years can provide credible estimates of the details of climate change on decadal to centennial time scales, showing that these details differ radically from what might be inferred from longer time scale information. High temporal resolution information can provide more meaningful estimates of the magnitude and pace of climate shifts, the location and timing of drivers of physiological stress, and the extent of novel climates. They also produce new opportunities to directly investigate whether short-term climate variability is more important in shaping biodiversity patterns, rather than gradual changes in long-term climatic means. Together these more accurate measures of past climate instability are likely to bring about a better understanding of the role of paleoclimatic change and variability in shaping current macro-ecological patterns in many regions of the world. This article is protected by copyright. All rights reserved.

International audience; With ongoing introductions into Australia since the 1700s, the European rabbit (Oryctolagus cuniculus) has become one of the most widely distributed and abundant vertebrate pests, adversely impacting Australia's biodiversity and agroeconomy. To understand the population and range dynamics of the species and its impacts better, occurrence and abundance data have been collected by researchers and citizens from sites covering a broad spectrum of climatic and environmental conditions in Australia. The lack of a common and accessible repository for these data has, however, limited their use in determining important spatiotemporal drivers of the structure and dynamics of the geographical range of rabbits in Australia. To meet this need, we created the Australian National Rabbit Database, which combines more than 50 yr of historical and contemporary survey data collected from throughout the range of the species in Australia. The survey data, obtained from a suite of complementary monitoring methods, were combined with high‐resolution weather, climate, and environmental information, and an assessment of data quality. The database provides records of rabbit occurrence (689,265 records) and abundance (51,241 records, >120 distinct sites) suitable for identifying the spatiotemporal drivers of the rabbit's distribution and for determining spatial patterns of variation in its key life‐history traits, including maximum rates of population growth. Because all data are georeferenced and date stamped, they can be coupled with information from other databases and spatial layers to explore the potential effects of rabbit occurrence and abundance on Australia's native wildlife and agricultural production. The Australian National Rabbit Database is an important tool for understanding and managing the European rabbit in its invasive range and its effects on native biodiversity and agricultural production. It also provides a valuable resource for addressing questions related to the biology, success, and impacts of invasive species more generally. No copyright or proprietary restrictions are associated with the use of this data set other than citation of this Data Paper.

In the face of increasing cumulative effects from human and natural disturbances, sustaining coral reefs will require a deeper understanding of the drivers of coral resilience in space and time. Here we develop a high-resolution, spatially explicit model of coral dynamics on Australia's Great Barrier Reef (GBR). Our model accounts for biological, ecological and environmental processes, as well as spatial variation in water quality and the cumulative effects of coral diseases, bleaching, outbreaks of crown-of-thorns starfish (Acanthaster cf. solaris), and tropical cyclones. Our projections reconstruct coral cover trajectories between 1996 and 2017 over a total reef area of 14,780 km(2), predicting a mean annual coral loss of -0.67%/year mostly due to the impact of cyclones, followed by starfish outbreaks and coral bleaching. Coral growth rate was the highest for outer shelf coral communities characterized by digitate and tabulate Acropora spp. and exposed to low seasonal variations in salinity and sea surface temperature, and the lowest for inner-shelf communities exposed to reduced water quality. We show that coral resilience (defined as the net effect of resistance and recovery following disturbance) was negatively related to the frequency of river plume conditions, and to reef accessibility to a lesser extent. Surprisingly, reef resilience was substantially lower within no-take marine protected areas, however this difference was mostly driven by the effect of water quality. Our model provides a new validated, spatially explicit platform for identifying the reefs that face the greatest risk of biodiversity loss, and those that have the highest chances to persist under increasing disturbance regimes.

Context Wildlife and pest managers and stakeholders should constantly aim to improve animal-welfare outcomes when foot-hold trapping pest animals. To minimise stress and trauma to trapped animals, traps should be checked at least once every 24h, normally as soon after sunrise as possible. If distance, time, environmental or geographical constraints prevent this, toxins such as strychnine can be fitted to trap jaws to induce euthanasia. However, strychnine is considered to have undesirable animal-welfare outcomes because animals are conscious while clinical signs of intoxication are present. A toxin considered more humane, para-aminopropiophenone (PAPP), is available to induce euthanasia in trapped animals but is untested for presentation and efficacy. Aim We tested the efficacy of two types of lethal trap device (LTD’s), each using a paste formulation of PAPP as the active toxin to replace the use of strychnine on foot-hold jaw traps. Methods Elastomer LTDs and PAPP-cloths were fitted to jaw traps set to capture wild dogs (Canis familiaris). Camera-trap data was used to record animal behaviours after capture and to determine the efficacy of both modalities. Key results Every trapped wild dog (n=117) gnawed at the elastomer LTD’s or PAPP-cloth attached to the trap jaws that restrained them; one dog failed to liberate the toxin. From the dogs caught in the main trial (n=56), a mortality rate of 84% and 87% was reported respectively. The mean time from trap-to-death for elastomer LTDs was 64min and 68min for PAPP-cloths. Conclusions Elastomer LTDs and PAPP cloths combined caused the mortality of 85% of captured dogs. This efficacy could be improved by adopting the recommendations discussed in the present study for deploying PAPP-based LTDs during trap deployment. Implications PAPP-based LTDs offer an alternative option to the use of strychnine and improve the welfare outcomes for trapped predators, especially where traps are not checked within the recommended 24-h period.

Cannibalism in predators has been reported for a range of species throughout the world, including observations of dingoes (Canis familiaris) eating dingoes in Australia. Here, we report on camera trap observations of dingoes feeding on the carcasses of dingoes and showing aggressive behaviours towards live-trapped conspecifics. At this site, cannibalism and conspecific aggression by dingoes was not caused by food shortages, but was more likely a result of high dingo density in a focal area. We present the first camera trap image observations of dingoes eating dingoes and describe aggressive encounters between live animals.