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The Kangean islands are a biologically poorly known archipelago situated in the Java Sea, Indonesia, 120 km directly north of Bali and 124 km off East Java. These islands host an avifauna comprising at least 13 endemic subspecies, two of which have by some sources recently been considered species. We combine historical published literature with our own surveys of the archipelago in 2007-2008, 2010 and 2023 to produce an updated list of the islands' birds (n=140 species) and their distribution across the islands. We evaluate in more detail the conservation status of all endemic taxa, as well as several others we consider to be of concern. Despite its current listing as Vulnerable on the IUCN Red List, the endemic Kangean Tit-babbler Mixornis prillwitzi is common in highly degraded habitats, including scrub, and is probably one of the islands' least threatened birds. However, because of trapping, the archipelago's endemic taxon of Red-breasted Parakeet Psittacula alexandri kangeanensis, and its populations of Green Junglefowl Gallus varius and Common Hill Myna Gracula religiosa are likely at risk of extirpation. The endemic taxon of White-rumped Shama Copsychus malabaricus nigricauda, sometimes afforded species rank as 'Kangean Shama', may already be (at least functionally) extinct in the main archipelago, with no record since 2007-2008. We recommend longer and more detailed surveys of the islands' birds, and that an effective protected area is established on the main Kangean island, which hosts the largest area of remaining forest in the archipelago and most of its endemic taxa. [ABSTRACT FROM AUTHOR]

Reducing extinction risk is a common aim of threatened species management. However, over the period 1990 to 2020, extinction risk was recently assessed as having declined in only 25 out of the 199 Australian bird taxa eligible for assessment. Here we analyse patterns that emerge from these taxa. Some of these improvements may be only temporary; the extinction risk of three taxa increased after it had initially declined. Invasive predator control on islands was the conservation intervention with greatest impact, benefitting 13 taxa (with nine of these from Macquarie Island). For four taxa, intensive management was the primary driver of reduced risk. Another four benefited from habitat protection and one from law enforcement. For seven taxa, conservation actions had no discernible effect; for two albatrosses a shift in fishing patterns may have reduced bycatch, for one, losses on the mainland meant that most birds now persist only in a stable island population and, for four taxa, reasons for changes in population trend are unknown. Never was there only one driver of reduced extinction risk with most taxa benefitting from at least five drivers. Macquarie Island was the only geographic cluster of taxa; there was little overlap among other taxa. Although the number of improvements is small, our results demonstrate that reduced extinction risk can be achieved with the right combination of targeted actions and, in some cases, serendipity. However, due to insufficient data, our ability to predict accurately the drivers of, or changes in, extinction risk for most species remains poor. Reductions in extinction risk are rare but achievable. Up to ten different factors contributed to reduced extinction risk in a taxon; there were rarely fewer than five. Extinction risk reduction had no geographical focus apart from the cluster of taxa on Macquarie Island. There is currently no widely accepted approach to classifying the many ways in which extinction risk can be reduced. Over a quarter of risk reduction examples were not the result of conservation interventions. [ABSTRACT FROM AUTHOR]

Most biodiversity monitoring globally tends to concentrate on trends in species' populations and ranges rather than on threats and their management. Here we review the estimated impact of threats and the extent to which their management is understood and implemented for all threats to all Australian threatened bird taxa. The assessment reports the situation in 2020 and how this differs from 2010. The most marked finding was that the impact of climate change has increased greatly over the last decade, and now surpasses invasive species as the threat imposing the heaviest threat load. Climate change has driven recent massive population declines from increased temperatures in tropical montane rainforests and from fire. For both direct climate change impacts and fire management, progress in understanding how to relieve the threats has been slow and patchy. Consequently, little effective management has occurred. By comparison, our analysis showed that the single successful campaign to eradicate introduced mammals from Macquarie Island relieved the total threat load on Australian threatened birds by 5%, and more than halved the load on the birds from oceanic islands. Protection or rehabilitation of habitat, particularly on islands, has also delivered measurable benefit as have, in the longer term, controls on longline fishing. Our approach can be used with other taxonomic groups to understand progress in research and management and to allow quantification of potential benefits from proposed actions, such as the national threatened species plan. Climate change is now the biggest threat to Australian threatened birds, but almost no research or management to mitigate this threat has been undertaken. Most successful threatened species management has been on small islands with invasive species eradication, habitat protection and restoration providing substantial benefits. The approach taken can be used to quantify the benefits of both past conservation interventions and potential interventions. Monitoring trends in threat load complements indices assessing trends in population size and extinction risk. [ABSTRACT FROM AUTHOR]

Over 750 native bird species reside in or regularly migrate to Australia, many of which have experienced rapid changes in habitat extent over the past two centuries. By 2020, eight taxa were considered Extinct and 10% threatened with extinction. Understanding the underlying extrinsic and intrinsic factors that increase extinction risk can allow prioritisation of conservation management and research. Here, we use state-of-the-art phylogenetic comparative models to reveal the most important biological traits that predispose Australian bird species to elevated extinction risk. We use an extensive database of their biological traits and relate these to each species' national and global IUCN extinction risk status as assessed over the past three decades (in 1990, 2000, 2010, and 2020). We show that high evolutionary distinctiveness (uniqueness), island endemism, and an inability to take advantage of agricultural habitats were the most important traits explaining elevated extinction risk in species when phylogeny is controlled for, suggesting that extinction risk is disproportionately high in species with high evolutionary distinctiveness. Extinct taxa were characterised by large body mass and island endemism compared to taxa extant in 2020. Our study provides the largest and most up-to-date analysis of the intrinsic traits of Australian birds in relation to their extinction risk, and can be used as a baseline in future studies, for prioritisation of conservation actions, and for policy advice on a broad scale. Phylogenetic analyses are a useful tool for anticipating extinction risk. Extinction risk over the past three decades is highest among species with a high level of evolutionary distinctiveness. Species-level assessments can mask higher extinction risk at the subspecies-level. Conservation actions that reduce extinction risk can influence the variables deemed important in predictive models. [ABSTRACT FROM AUTHOR]