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Nomadic species are challenging to conserve, because their high mobility and irregular settlement patterns make it difficult to implement targeted conservation actions. Here, we report on the first sustained attempt to protect nests of Critically Endangered Regent Honeyeaters from predation and to release zoo-bred birds into a wild breeding event. During the 2023 breeding season, targeted culling of known nest predator species within the area of 10–12 wild breeding pairs within Capertee National Park was associated with a daily nest survival rate of 97.9%. This equated to an overall nest success rate of 48.6% and resulted in the fledging of 18 juveniles from nine nests – double the average nest success rate from 2015, 2016 and 2017 (24.1%) when Regent Honeyeaters bred in the same location. Population viability analysis indicates nest protection alone could slow the rate of population decline, but its effectiveness depends on the proportion of nests that can be located and protected each year. Fourteen zoo-bred Regent Honeyeaters were released approximately half way through the breeding event. Seven zoo-bred birds were confirmed alive 5 weeks post-release, but no zoo-bred birds released in 2023 attempted to breed in this year. Although our sample is small and prone to stochastic effects, we provide non-experimental evidence that nest predator management can play a key role in boosting recruitment of juvenile Regent Honeyeaters to the wild population. In combination with the reintroduction of zoo-bred birds and habitat restoration, nest predator management can help prevent imminent extinction of the Regent Honeyeater. [ABSTRACT FROM AUTHOR]

Small, fragmented, or isolated populations are at risk of population decline due to fitness costs associated with inbreeding and genetic drift. The King Island scrubtit Acanthornis magna greeniana is a critically endangered subspecies of the nominate Tasmanian scrubtit A. m. magna, with an estimated population of <100 individuals persisting in three patches of swamp forest. The Tasmanian scrubtit is widespread in wet forests on mainland Tasmania. We sequenced the scrubtit genome using PacBio HiFi and undertook a population genomic study of the King Island and Tasmanian scrubtits using a double-digest restriction site-associated DNA (ddRAD) dataset of 5,239 SNP loci. The genome was 1.48 Gb long, comprising 1,518 contigs with an N50 of 7.715 Mb. King Island scrubtits formed one of four overall genetic clusters, but separated into three distinct subpopulations when analyzed independently of the Tasmanian scrubtit. Pairwise F ST values were greater among the King Island scrubtit subpopulations than among most Tasmanian scrubtit subpopulations. Genetic diversity was lower and inbreeding coefficients were higher in the King Island scrubtit than all except one of the Tasmanian scrubtit subpopulations. We observed crown baldness in 8/15 King Island scrubtits, but 0/55 Tasmanian scrubtits. Six loci were significantly associated with baldness, including one within the DOCK11 gene which is linked to early feather development. Contemporary gene flow between King Island scrubtit subpopulations is unlikely, with further field monitoring required to quantify the fitness consequences of its small population size, low genetic diversity, and high inbreeding. Evidence-based conservation actions can then be implemented before the taxon goes extinct. [ABSTRACT FROM AUTHOR]

Implementing effective, affordable and ethical conservation management will be crucial for minimising future biodiversity losses. Such management requires reliable foundational evidence to help managers make informed choices about how to address the needs of their target species. Unfortunately, such evidence is still lacking for many species and management scenarios.One major global challenge is improving the reproductive success of threatened species in the context of predation. We conducted a systematic review and meta‐analysis of in situ experiments that used non‐lethal methods to protect bird nests against predators, with the aims of summarising global trends in nest protection efforts, comparing the effectiveness of different protection measures and informing future research and management. We considered peer‐reviewed studies in English.We detected a large geographic and taxonomic bias in the evidence base with 58% of articles conducted in North America and 76% on ground‐nesting birds. Less than 3% of articles involved taxa listed as Endangered or Critically Endangered and 51% of study units lasted just a single breeding season.Nests protected with exclosures, fences and guards were more likely to be successful than their unprotected controls. Interventions involving deterrents, conditioned taste aversion, chemical camouflage and diversionary feeding did not have a significant positive effect on nest success, but the interventions in these categories were less common and more diverse in nature.Synthesis and applications. To increase their conservation value, future non‐lethal nest protection experiments should whenever possible clearly state overall aims, take place over multiple seasons, use a comparable control and test non‐lethal protection methods independently of lethal predator control. Greater focus is required on under‐studied taxa such as cup‐nesting songbirds and birds in South America, Africa and Asia, and novel protection techniques such as deterrents and chemical camouflage. Practitioners should consider the evidence we synthesise here when deciding whether non‐lethal nest protection approaches are optimal for their study system, to increase conservation success and reduce ethical and financial costs. [ABSTRACT FROM AUTHOR]

The south‐eastern corner of the Australian continent was once crisscrossed by the nomadic flight paths of the Regent Honeyeater. For hundreds of thousands of years, they winged their way up and down this vast continent. Today, however, the species is listed as critically endangered and is just clinging to existence. This multimedia essay tells the story of this decline, exploring the complex, co‐shaping, relationships between individual birds and their flocks, their songs, and their forests. While these are relationships that might be glossed as being social, cultural, and ecological (respectively), and so belonging to separate domains of life, they are in reality delicately interwoven elements of what it is to be a Regent Honeyeater; relationships that, taken together, have been integral to the emergence and ongoing life of this species. In attending to the breakdown of these relationships in our present time, this essay seeks to develop new resources for storying loss in a time of ongoing extinctions. Bringing text into conversation with images and audio, the essay works to draw the reader/viewer/listener into an encounter with an unravelling world. Ultimately, our aim has been to create an essay in which the conceptual ideas, the design, and the biology of the species described, are brought into some sort of alignment that allows them to become mutually reinforcing elements of a storied encounter. Our reflection on the process of creating this essay are provided in the accompanying exegetical commentary. [ABSTRACT FROM AUTHOR]

There are many impediments to conserving threatened birds. Some can be overcome through concerted action across multiple species while others require species-specific research and intensive management. We assess the feasibility of managing 202 threats identified in the Action Plan for Australian Birds across 217 Australian threatened bird taxa against five metrics – financial, technical, temporal, political and social. A higher percentage of all threats to all taxa was assessed as having low or very low financial (43%), technical (32%) or temporal (29%) feasibility than political (9%) or social feasibility (7%). The feasibility of managing the most difficult threat to a taxon was low or very low for 52% of the threats identified. Within Australia, the main impediments to addressing most threats are technical and financial, indicating that research and funding should be domestic conservation priorities. Addressing threats linked to habitat destruction/degradation, climate change, invasive species and pollution is limited by the long timescales required to alleviate them, emphasising the urgency of commencing action. Outside Australia, social and political constraints are the main impediments to Australian conservation managers influencing action on habitat loss, species over-exploitation and climate change, but there are also technical, financial and temporal impediments to reducing threats from pollution, invasive species and climate change. Advocacy is therefore also important for addressing threats facing birds outside Australia. Our study provides a platform upon which to build more explicit and efficient management of threatened birds, prioritise efforts in research, funding and advocacy and contribute to reducing losses from Australia's avifauna. Feasibility analysis can identify the principal constraints on taxon recovery and help shape funding threat-based or species-specific priorities. In Australia, financial and technical deficits are the principal constraints on threat mitigation, emphasising the need for funding and research. Outside Australia, social and political issues are the major problem, requiring diplomacy to effect change. Many threats also face temporal constraints, highlighting the need for sustained funding. [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]

The breeding of threatened species in captivity for release is a central tool in conservation biology. Given gloomy predictions for biodiversity trends in the Anthropocene, captive breeding will play an increasingly important role in preventing future extinctions. Relative to the wild, captive environments drastically alter selection pressures on animals. Phenotypic change in captive animals in response to these altered selection pressures can incur fitness costs post‐release, jeopardising their potential contribution to population recovery. We explore the ways in which captive environments can hinder the expression of wild phenotypes. We also stress that the phenotypes of captive‐bred animals differ from their wild counterparts in multiple ways that remain poorly understood. We propose five new research questions relating to the impact of captive phenotypes on reintroduction biology. With better use of monitoring and experimental reintroductions, a more robust evidence base should help inform adaptive management and minimise the phenotypic costs of captivity, improving the success of animal reintroductions. [ABSTRACT FROM AUTHOR]

Addressing threats to biodiversity from pest species is a global challenge. One such challenge is to mitigate the impact of an overabundant Australian songbird, the noisy miner Manorina melanocephala, on woodland birds. The overabundance of noisy miners is listed as a key threatening process under federal biodiversity legislation, but current understanding of where and how noisy miner populations can be managed to yield conservation benefits is unclear. We evaluated the effectiveness of noisy miner removal across 12 treatment areas totaling 3913 ha and nine control areas totaling 1487 ha important for the critically endangered regent honeyeater Anthochaera phrygia. Removal of noisy miners significantly reduced their densities in all but one of the treatment areas. In 10 of the 12 treatment areas, noisy miner densities remained below an impact threshold of 0.65–0.83 birds ha−1 for at least 3 to more than 12 months. The percentage of suitable noisy miner habitat in the surrounding landscape was not a strong predictor of noisy miner management success. Regent honeyeaters occupied six treatment areas, nesting successfully in four. The abundance of other songbirds increased post‐miner removal in seven areas, decreased in three, and was mixed in two. Data from the control areas showed some variation in songbird numbers was independent of noisy miner management. We conclude that noisy miners can be managed in areas of high conservation value for a minimum cost of AUD $10 ha−1. Larger treatment areas may be more important than the broader landscape context in maintaining long‐term noisy miner suppression. Standardized, long‐term monitoring is crucial to identify not only the drivers of pest species recolonization but also locations where threats from pests on endangered species can be addressed effectively while minimizing animal welfare and financial costs. [ABSTRACT FROM AUTHOR]

Animals that breed in cavities formed through decay or mechanical damage often face limitations to reproduction due to a shortage of nest sites. Artificial nests are commonly deployed to increase the short‐term availability of breeding sites for these species. Often this is an effective approach; however, artificial nests are costly and may be ignored by the target species or inadvertently benefit nontarget species. Here we consider the use of modified natural hollows and artificial nest sites to support endangered Norfolk Island green parrots Cyanoramphus cookii. We recorded the characteristics of all modified and artificial nests in the Norfolk Island National Park and used 8 years of nesting data to study nest selection by green parrots and introduced crimson rosellas Platycercus elegans. Artificial nests (those lacking a natural base) were never used by green parrots. Nests with thicker walls were more likely to be used by green parrots, but there was no nest site characteristic that predicted frequency of use. Crimson rosella nest use was not predicted by any of the nest characteristics measured. A better understanding of the reasons behind green parrots' avoidance of artificial nests and preference for thicker nest walls is required to inform the future design and management of nest sites. Our study shows that evaluation of how artificial sites are used by the target species is important to maximize the efficacy of conservation efforts. [ABSTRACT FROM AUTHOR]