Bush Heritage Australia is a non-profit organisation based in Melbourne, Australia, that operates throughout Australia. It was previously known as the Australian Bush Heritage Fund, which is still its legal name. It purchases land, assessed as being of outstanding conservation value, from private owners, to manage as wildlife reserves in perpetuity. It also partners with existing land owners, including Aboriginal groups, to help plan and manage conservation work of important landscapes. It does so to protect endangered species and preserve Australia's biodiversity. By 2020 the organisation was contributing to the protection of 11.3 million hectares on its reserves and partnership lands. There were 6,700 Australian species recorded on its reserves and partnership properties, including 226 threatened species.
At least 40 Australian mammal spcies have been driven to extinction since European colonization in 1788. For conservation management to be effective, it is vital that the reasons for historical extinctions and ongoing declines are understood and remedied. A recent article (Wallach and Lundgren 2025) concluded that there was no compelling evidence that two introduced predators (domestic cats and red foxes) were primary causes of these mammal losses. We refute that article, finding substantial flaws in its premises, analyses, data, interpretations, and conclusions. Using multiple lines of evidence, we show that these two predators are strongly implicated in most Australian mammal extinctions and in the ongoing imperilment of numerous extant species. The devastating impact of cats and foxes on Australia's mammals has been widely recognized by conservation managers who have, in response, implemented national programs to control these predators, producing widely recognized benefits for one of the world's most remarkable native mammal faunas.
Agricultural landscapes with poor water retention, often referred to as “leaky landscapes”, represent a growing agro-environmental challenge. Although a wide range of landscape rehydration interventions have been proposed, a comprehensive understanding of the global research landscape, key themes, and knowledge gaps within this field remains limited. This review uses a bibliometric analysis and literature synthesis approach to provide quantitative insights into the landscape rehydration research over the past 100 years. This examines bibliometric indicators such as global research trend over time, keywords co-occurrence, citation impact, and collaboration patterns among countries. We found that landscape rehydration was first reported in the mid-1900s and has continued to expand to over 104 countries, focusing on intervention effectiveness, benefits, and limitations. Despite the growing body of literature, the review revealed that most studies evaluate individual interventions in isolation and provide limited guidance on how to select appropriate interventions under varying conditions. This complexity leaves land managers without clear direction for selecting interventions across different landscape contexts. To address this gap, the insights from the literature review were synthesised into a practical decision-support framework that integrates environmental suitability, technical feasibility, economic considerations, and socio-environmental impacts. Further, the framework is demonstrated through a case study application in the Turnip Creek catchment in Victoria, Australia. We identified that pasture improvement, contour ripping, and vegetative cover enhancement are suitable interventions, highlighting the potential support of the framework for future rehydration projects.
1. Climate change and habitat degradation are major threats to wildlife worldwide. Although developing animals are particularly sensitive to their impacts, with fitness consequences for individuals that cascade to population persistence, their combined effect and potential interaction are rarely considered. Here, we address this in an indicator species for a biodiverse riparian ecosystem in Australia's tropical savanna, an understudied region threatened by habitat loss and climate change. 2. We investigate the effect of habitat, temperature and rainfall on nestling condition and subsequent survival in an individually marked population of the Endangered purple-crowned fairy-wren (Malurus coronatus coronatus). Leveraging a high-quality 10-year dataset of nestling measurements, we control for pertinent factors influencing growth (e.g. food provisioned) and quantify short- and long-term survival with high accuracy. 3. Higher ambient temperatures in the week after hatching reduced nestling body condition (mass relative to body size). 4. Poor, degraded habitat (lower density of mid-storey vegetation) decreased nestling body condition, regardless of temperature or rainfall. 5. Lower body condition as a nestling did not affect survival to nutritional independence (12 weeks) but decreased survival from independence to adulthood (2 years). Poor habitat also directly decreased survival to adulthood, compounding this effect. 6. Taken together, our results show that climate warming and habitat degradation are additive threats to nestling purple-crowned fairy-wrens that reduce survival to adulthood. Future research should address the mechanisms underlying the protective effect of high-quality habitat and explore how exposure to these threats during development affects fitness in other species. 7. Policy implications. Our study shows that improving habitat quality is critical for riparian wildlife as the climate warms and that supporting long-term studies is important for detecting cryptic effects of anthropogenic threats. The Australian monsoonal savanna is projected to warm by 3.5 degrees C by 2090, and our models predict an associated average of 2.2% decrease in purple-crowned fairy-wren survival. This could be offset by a 7% increase in average habitat quality, underscoring the importance of high-density riparian habitat as a climate refuge. Conservation strategies for climate warming should protect high-quality habitat and improve low-quality patches, for example, through effective fire management and reduction of high-intensity grazing.
This study investigates the population dynamics and seasonal reproductive patterns of Gambusia holbrooki, an invasive fish threatening biodiversity within arid springs of the Edgbaston Spring complex in Queensland, Australia. Using daily aging techniques, we uncover critical life history traits that inform targeted species management. Our findings reveal marked sex-specific mortality rates, with males exhibiting higher mortality than females, a pattern consistent with findings from Tasmania. Reproductive activity peaks were observed between September and November, but persisted throughout the year, excluding January and April of 2020, likely due to elevated water temperatures during these months. Growth modeling identified the power function as the best fit for describing G. holbrooki growth trajectories. These insights highlight the importance of seasonally informed control strategies to mitigate the ecological impact of this pest species. The study provides essential data to support conservation efforts and guide effective management of invasive fish in fragile arid spring ecosystems.
Wild herbivores threaten vegetation recovery on dryland conservation reserves globally. Monitoring herbivore impacts in remote drylands is difficult because vegetation biomass transitions between living and senescent states in response to irregular precipitation events. However, land managers need detailed understanding of the impacts that wild herbivores have on vegetation to develop and refine herbivore management strategies. Remote sensing provides the ability to assess grazing impacts on living and senescent vegetation with high temporal and spatial resolution. Here, we use Sentinel-2 satellite imagery to investigate how grazing by kangaroos and rabbits impacted fractional cover of photosynthetic (PV) and non-photosynthetic (NPV) vegetation over a 7-year period on three dryland reserves with experimental herbivore exclusion plots. We compared PV and NPV cover in plots that were accessible to all herbivores, accessible to kangaroos only, and inaccessible to both rabbits and kangaroos. Generalized linear mixed models were used to determine if the grazing impacts of rabbits and kangaroos varied from each other, between reserves, and in response to variable rainfall patterns. Grazing impacts varied between each herbivore, conservation reserve, and between PV and NPV. PV was only weakly limited by kangaroos across all reserves and antecedent rainfall totals. NPV was limited by rabbits and kangaroos, with grazing having stronger impacts on NPV than PV. The grazing impacts of rabbits and kangaroos varied spatially with evidence that NPV was limited by kangaroos only, by rabbits only, and by both species across different reserves. Both herbivores had stronger impacts on NPV as antecedent rainfall decreased. Our results show that the impact of herbivores on vegetation biomass is greatest during periods of dry climatic conditions. These findings contribute to a growing body of evidence showing that grazing by wild herbivores can have detrimental impacts on dryland ecosystems by disrupting ecological processes supported by NPV. Our results highlight the importance of herbivore management during productive periods to ensure NPV is retained during periods of low rainfall.
