Understanding the processes that lead to species extinctions is vital for lessening pressures on biodiversity. While species diversity, presence and abundance are most commonly used to measure the effects of human pressures, demographic responses give a more proximal indication of how pressures affect population viability and contribute to extinction risk. We reviewed how demographic rates are affected by the major anthropogenic pressures, changed landscape condition caused by human land use, and climate change. We synthesized the results of 147 empirical studies to compare the relative effect size of climate and landscape condition on birth, death, immigration and emigration rates in plant and animal populations. While changed landscape condition is recognized as the major driver of species declines and losses worldwide, we found that, on average, climate variables had equally strong effects on demographic rates in plant and animal populations. This is significant given that the pressures of climate change will continue to intensify in coming decades. The effects of climate change on some populations may be underestimated because changes in climate conditions during critical windows of species life cycles may have disproportionate effects on demographic rates. The combined pressures of land‐use change and climate change may result in species declines and extinctions occurring faster than otherwise predicted, particularly if their effects are multiplicative.

Incidence, or compositional, matrices are generated for a broad range of research applications in biology. Zeta diversity provides a common currency and conceptual framework that links incidence‐based metrics with multiple patterns of interest in biology, ecology, and biodiversity science. It quantifies the variation in species (or OTU) composition of multiple assemblages (or cases) in space or time, to capture the contribution of the full suite of narrow, intermediate, and wide‐ranging species to biotic heterogeneity. Here we provide a conceptual framework for the application and interpretation of patterns of continuous change in compositional diversity using zeta diversity. This includes consideration of the survey design context, and the multiple ways in which zeta diversity decline and decay can be used to examine and test turnover in the identity of elements across space and time. We introduce the zeta ratio–based retention rate curve to quantify rates of compositional change. We illustrate these applications using 11 empirical data sets from a broad range of taxa, scales, and levels of biological organization—from DNA molecules and microbes to communities and interaction networks—including one of the original data sets used to express compositional change and distance decay in ecology. We show (1) how different sample selection schemes used during the calculation of compositional change are appropriate for different data types and questions, (2) how higher orders of zeta may in some cases better detect shifts and transitions, and (3) the relative roles of rare vs. common species in driving patterns of compositional change. By exploring the application of zeta diversity decline and decay, including the retention rate, across this broad range of contexts, we demonstrate its application for understanding continuous turnover in biological systems.

Restoration of degraded landscapes through replantings of native vegetation has been proceeding in response to habitat loss and fragmentation and plummeting biodiversity. Little is known about whether the investments in ecological restoration have resulted in biodiversity benefits. We evaluated the potential of restored sites to support populations by assessing bird breeding activity. We surveyed 21 revegetated sites of various ages (9-111 years) in the box-ironbark region of Victoria, Australia. Sites differed in landscape context, patch features and in-site characteristics. The latter, including whether sites were grazed, amounts of fallen timber and numbers of remnant trees, were most important in affecting overall bird breeding activity. Patch-configuration (e.g., shape, area) was of secondary importance. Landscape context appeared to have little effect on bird breeding except for one species. While these results suggest that in-site habitat structure is the predominant driver, we caution against dismissing the importance of patch characteristics and landscape context for two reasons. First, the available sites covered a relatively small range of areas (<54 ha), and we could not provide a broad range of landscape-contextual contrasts given that we could only use existing plantings. Second, much of the breeding activity was by bird species known to be tolerant of smaller woodland areas or of the open countryside. We show that there is very little breeding activity in replantings by species that have declined dramatically in rank abundance between large 'reference' areas and fragmented landscapes. It seems likely that most replantings provide habitat configurations unsuited for dealing with declines of species most vulnerable to habitat loss and fragmentation.

Aim Climate refugia will become increasingly important for biota as climate change causes an increased frequency and intensity of extreme events, such as drought. Floodplains are potential drought refugia because they have cooler and more mesic microclimates than adjacent areas, and greater water availability through shallower groundwater and flooding. We explored the role of floodplains as drought refugia by estimating the resistance and resilience of terrestrial birds over a 13‐year drought (the ‘Big Dry’) and for 4 years following the break in the drought in floodplain and non‐floodplain zones. Location Murray–Darling Basin, Australia. Methods We used Atlas of Australian Birds survey data from more than 39,000 surveys at over 28,000 sites to estimate trends in reporting rates in floodplain and non‐floodplain zones for 144 bird species during extended drought (1998–2009) and in the post‐drought period (2010–13). Results There was greater resistance to drought in floodplain zones: fewer species declined in floodplain zones (19%) than in non‐floodplain zones (29%) during the Big Dry, and more species had elevated reporting rates (13% vs. 8%). More species showed a recovery in reporting rates in non‐floodplain zones (40.3%) than in floodplain zones (15.3%) during the post‐drought period, which was expected because declines during the Big Dry were more common in non‐floodplain zones. There was some evidence for limitations in the resilience of floodplain avifauna, with only 17.9% of species that declined in floodplain zones during the drought subsequently recovering. Conclusions Floodplains appear to enhance resistance to drought for many bird species, and are likely to be particularly important as refugia in areas with an arid climate. However, their role in resilience is less clear. Floodplain ecosystems require long‐term management to relieve pressures and to restore their ecological condition so that their role as drought refugia is maintained or enhanced.

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Modern zoos are increasingly taking a leading role in emergency management and wildlife recovery. In the face of climate change and the predicted increase in frequency and magnitude of catastrophic events, zoos provide specialised expertise to assist wildlife welfare and endangered species recovery. In the 2019–2020 Australian bushfire season, now called Australia’s Black Summer, a state government-directed response was developed, assembling specialised individuals and organisations from government, non-government organisations, research institutions, and others. Here, we detail the role of Zoos Victoria staff in wildlife triage and welfare, threatened species evacuation and recovery, media and communications, and fundraising during and after the fires. We share strategies for future resilience, readiness, and the ability to mobilise quickly in catastrophic events. The development of triage protocols, emergency response kits, emergency enclosures, and expanded and new captive breeding programs is underway, as are programs for care of staff mental health and nature-based community healing for people directly affected by the fires. We hope this account of our response to one of the greatest recent threats to Australia’s biodiversity, and steps to prepare for the future will assist other zoos and wildlife organisations around the world in preparations to help wildlife before, during, and after catastrophic events.

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Climate change alters the frequency and severity of extreme events, such as drought. Such events will be increasingly important in shaping communities as climate change intensifies. The ability of species to withstand extreme events (resistance) and to recover once adverse conditions abate (resilience) will determine their persistence. We estimated the resistance and resilience of bird species during and after a 13-year drought (the 'Big Dry') in floodplain forests in south-eastern Australia. We conducted bird surveys at the beginning and end of the Big Dry, and after the abrupt end to the drought (the 'Big Wet'), to evaluate species-specific changes in reporting rates among the three periods. We assessed changes in bird-breeding activity before and after the Big Wet to estimate demographic resilience based on breeding. Between the start and the end of the Big Dry (1998 vs. 2009), 37 of 67 species declined substantially. Of those, only two had increased reporting rates after the Big Wet (2009 vs. 2013) that were equal to or larger than their declines, while three partially recovered. All other declining species showed low resilience: 25 showed no change in reporting rates and seven declined further. The number of breeding species and total breeding activity of all species declined after the Big Wet, and there was no change in the number of young produced. The Big Dry caused widespread declines in the floodplain avifauna. Despite the drought being broken by 2 years of well-above-average rainfall and subsequent near-average rainfall, most species showed low resilience and there was little indication that overall breeding had increased. The effects of drought appeared to be pervasive for much of the floodplain avifauna, regardless of species traits (species body mass, fecundity, mobility or diet). Ecosystems such as these are likely to require active management and restoration, including reinstatement of natural flooding regimes, to improve ecological condition, to enhance resistance and resilience to extreme climate events.