The catastrophic declines of three species of ‘Critically Endangered’ Gyps vultures in South Asia were caused by unintentional poisoning by the non-steroidal anti-inflammatory drug (NSAID) diclofenac. Despite a ban on its veterinary use in 2006 (India, Nepal, Pakistan) and 2010 (Bangladesh), residues of diclofenac have continued to be found in cattle carcasses and in dead wild vultures. Another NSAID, meloxicam, has been shown to be safe to vultures. From 2012 to 2018, we undertook covert surveys of pharmacies in India, Nepal and Bangladesh to investigate the availability and prevalence of NSAIDs for the treatment of livestock. The purpose of the study was to establish whether diclofenac continued to be sold for veterinary use, whether the availability of meloxicam had increased and to determine which other veterinary NSAIDs were available. The availability of diclofenac declined in all three countries, virtually disappearing from pharmacies in Nepal and Bangladesh, highlighting the advances made in these two countries to reduce this threat to vultures. In India, diclofenac still accounted for 10–46% of all NSAIDs offered for sale for livestock treatment in 2017, suggesting weak enforcement of existing regulations and a continued high risk to vultures. Availability of meloxicam increased in all countries and was the most common veterinary NSAID in Nepal (89.9% in 2017). Although the most widely available NSAID in India in 2017, meloxicam accounted for only 32% of products offered for sale. In Bangladesh, meloxicam was less commonly available than the vulture-toxic NSAID ketoprofen (28% and 66%, respectively, in 2018), despite the partial government ban on ketoprofen in 2016. Eleven different NSAIDs were recorded, several of which are known or suspected to be toxic to vultures. Conservation priorities should include awareness raising, stricter implementation of current bans, bans on other vulture-toxic veterinary NSAIDs, especially aceclofenac and nimesulide, and safety-testing of other NSAIDs on Gyps vultures to identify safe and toxic drugs.

The ‘Endangered’ Cape Vulture Gyps coprotheres has been monitored across its range for decades through disparate studies varying in geographical scope and length. Yet, no long-term, range-wide survey exists for the species. Coordinated monitoring across the range of the Cape Vulture would be logistically challenging but provide a holistic view of population dynamics in this long-lived species that forages across much of southern Africa. Here, we report breeding pair counts from seven colonies in the Cape Vulture’s north-eastern breeding region from 2010 to 2019. We used state-space models to assess population growth across time. Manutsa, Soutpansberg, and Nooitgedacht colonies increased significantly over the study period, with three other colonies having positive estimates of population growth, but 95% credible intervals overlapped zero. The smallest colony at Moletjie is declining toward extirpation; only one breeding pair remained in 2019. Our results suggest the north-eastern population has been stable or increasing since 2010 with our 2019 surveys counting 2,241 breeding pairs across all sites. Indeed, there is an 89% chance that the population across the colonies we monitored increased from 2010 to 2019. Coordinated, range-wide, full-cycle monitoring is needed to thoroughly assess conservation status and efficacy of conservation actions taken for this endangered species.

Avian electrocutions are a global conservation problem. Power outages associated with electrocutions are problematic for electric utilities focused on delivering reliable electric power. We used contextual data, photographs, line voltage, outage type and assessments of power line components to quantify outage-causing avian electrocutions throughout each of Iran’s 31 provinces. We evaluated records of 222 avian-caused outages involving 235 electrocuted birds in 2018. Of these, 14.5% involved species of conservation concern, and a few (at least eight) sparked fires when the plumage of electrocuted birds ignited and fell into dry vegetation. Most avian-caused outages (96%) involved distribution voltages, and 91% involved phase-to-ground contacts attributable to grounded concrete pylons with grounded steel crossarms. These are the most common type of power line structure in Iran. Insulators were involved in 37% of outage-causing avian electrocutions, fused cutouts 29%, transformers 33%, and midspan collisions 1%. Given the numbers of these components in the electrical system, fused cutouts and transformers were involved in more outage-causing avian electrocutions than expected due to chance. The average body size of electrocuted birds was largest for incidents involving suspension insulators, smaller for birds electrocuted on other insulators, and smallest for electrocutions on fused cutouts and transformers. Given that most avian electrocutions do not cause outages and given the similarity across electric systems in the region, our findings likely indicate a much larger avian electrocution concern throughout the middle east. Retrofitting power line components to reduce avian contacts would reduce impacts to wildlife and improve the electrical system’s reliability, reduce costs associated with unplanned outages, and reduce risks associated power line ignitions of fires.

Avian species often take advantage of human-made structures, such as perching on power poles, although this can lead to negative effects for both birds and infrastructure. It has been demonstrated that anchor-type pylons, with strain insulators, are amongst the most dangerous of these structures. Our goal was to develop a methodological approach to evaluate the ways in which raptors perch on the six most commonly used strain insulator configurations in Spain, and to build a risk index that can be used to prioritise them. To study the ways raptors perch, we worked with six wildlife rescue centres in central Spain for almost a year assessing these six strain insulator configurations in 83 perch trials with 176 raptors in ample flying pens. We analysed 475 complete survey days, with an approximate number of 258,960 analysed pictures, including 6,766 perchings on strain insulators. We assessed the influential factors for these 6,766 perchings and developed a novel approach to prioritise strain insulator configurations that can be used anywhere. Our results suggest that longer insulator strains (i.e. PECA-1000 and Caon-C3670) are the safest, according to our prioritization criteria, although these results require further assessment in the field. Managers and conservationists should take into account these results to improve management and conservation actions.

Understanding the environmental drivers of demographic processes is a prerequisite for providing the evidence-based conservation guidance and management actions required to address management goals at population level. Human activities, to which most species are not adapted, are having an ever-increasing impact on the environment. Most policies and strategies focus on broad-scale conservation actions and disregard the fact that this type of action may not be adequate at local scale. In addition, even though the main conservation targets are well known, managers and practitioners lack an explicit framework in which to identify the varying requirements of site-specific conservation actions. Our aim was to provide an accurate tool for prioritizing specific local-scale conservation actions for endangered territorial birds. In this study we describe our proposed framework using a population of the endangered Bonelli’s Eagle Aquila fasciata as a case study. We identified the most relevant environmental drivers linked to demographic parameters (occupation, productivity and survival) at local scale shaping the dynamics of the Bonelli’s Eagle population in Catalonia (Spain). This information will be useful for designing specific local-scale conservation actions in eagles’ territories with low demographic parameter values. This is a good example of how applied research and achievable conservation practices are applicable to other Bonelli’s eagle populations and to those of other endangered raptors.

Reintroductions aim to re-establish a viable population within the indigenous range of living organisms, especially of threatened species. The population of the Asian Crested Ibis Nipponia nippon, a well-known ‘Endangered’ bird species, has increased over 100 times since wild populations were rediscovered in 1981, and several reintroduction projects were subsequently carried out in its former range. An experimental release of the Asian Crested Ibis was conducted in Qianhu National Wetland Park located in the southern part of the Loess Plateau, China. It is vitally important to monitor released birds (at least their survival and breeding), to inform subsequent releases in other suitable sites. During extensive post-release monitoring, data on capture-recapture and reproductive status were obtained using banding, radiotelemetry, and field observations. Using the Cormack-Jolly-Seber (C-J-S) model, the average annual survival rates were estimated to be 0.569 (95% CI: 0.353–0.762) for released individuals and 0.643 (95% CI: 0.038–0.987) for all individuals. From 2014 to 2018, a total of 14 breeding pairs produced 28 eggs and 10 fledglings with successful reproduction of the second generation. The mean clutch size was 2.07 ± 0.25 (n = 29), and the breeding success was 34.5%. Predation and poor habitat quality have been shown to be the main factors affecting the reintroduced population at establishment stage. Some management suggestions at the metapopulation and ecosystem levels, including further release, predator control and habitat improvement, have been proposed.

White-bellied Heron Ardea insignis (WBH) is critically endangered, but we lack data on many aspects of its basic ecology and threats to the species are not clearly understood. The goal of this study was to analyse WBH foraging microhabitat selection, foraging behaviour, and prey preferences in two river basins (Punatsangchhu and Mangdechhu) in Bhutan which are likely home to one of the largest remaining populations of WBH. We also explored the relationship between the relative abundance of the WBH and prey biomass catch per unit effort within four foraging river microhabitats (pool, pond, riffle and run). Prey species were sampled in 13 different 100-m thalweg lengths of the rivers using cast nets and electrofishing gear. Riffles and pools were the most commonly used microhabitats; relative abundance was the highest in riffles. The relative abundance of WBH and prey biomass catch per unit effort (CPUE) also showed a weak but significant positive correlation (rs = 0.22). The highest biomass CPUE was observed in riffles while the lowest was found in the ponds. From the 97 prey items caught by the WBH, 95% of the prey were fish. The WBH mainly exploited three genera of fish (Garra, Salmo, and Schizothorax) of which Schizothorax (64%) was the most frequently consumed. This study provides evidence in support of further protection of critical riverine habitat and fish resources for this heron. Regular monitoring of sand and gravel mining, curbing illegal fishing, habitat restoration/mitigation, and developing sustainable alternatives for local people should be urgently implemented by the government and other relevant agencies. Further study is also required for understanding the seasonal variation and abundance of its prey species in their prime habitats along the Punatsangchhu and Mangdechhu basins.

The Scaly-sided Merganser Mergus squamatus is a globally ‘Endangered’ species breeding in north-east Asia. Limited by information on the geographic distribution of suitable habitat, the conservation management programme has not been comprehensive or spatially explicit for the breeding population. This study combines potentially important environmental variables with extensive data on species occurrence to create the first species distribution model for the breeding Scaly-sided Merganser, followed by a GAP analysis to highlight the unprotected areas containing suitable habitat. The predictive map showing the most suitable breeding habitat for the Scaly-sided Merganser covered broad-leaved deciduous forest distributed in six provincial regions in south-east Russia, north-east China, and North Korea. The conservation GAP, i.e. 90% (38,813 km2) of highly suitable habitat, is mainly concentrated in the Sikhote-Alin and Changbai mountain ranges. This study suggests that prioritizing conservation of unprotected broad-leaved deciduous riverine forests within the above two mountainous regions should be included in international conservation planning, and the remaining suitable patches need to be preserved to allow range expansion in future. This predictive map improves the expert global assessment of breeding Scaly-sided Merganser distribution and provides a basic reference for establishing conservation areas or implementing conservation actions for the breeding Scaly-sided Merganser in north-east Asia.

The Giant Nuthatch Sitta magna is a globally endangered species presumed to be declining, for which basic parameters of population and habitat associations remain largely unquantified. We focused on Myanmar, which potentially constitutes ~30% of the Giant Nuthatch global range and yet lacks recently published records. Our objectives were to survey key potential Giant Nuthatch localities in, or near, historical locations in Southern Shan State, assess its population status, and quantify habitat associations. Preliminary locality surveys focused on four potential forest patches, assessed by walking approximately 40 km of trails. The species was found in only one of the four localities (Mt. Ashae Myin Anauk Myin [AMAM]), an 18 km2 forest patch in Pindaya and Lawksawk Townships. Here, point counts and vegetation surveys were conducted at 46 locations using an adaptive cluster sampling design. N-mixture models were applied to estimate abundance and identify habitat variables correlated with abundance and detection probability. We also conducted a brief quantitative assessment of tree use and foraging behaviour during one breeding season. Our population estimate for AMAM was 56 individuals (95% CI 25–128) based on a sampled area of 3.25 km2. Abundance was positively associated with larger diameter trees, a higher proportion of pine and oak combined based on their total basal area, and negatively correlated with elevation. Foraging data suggested that Giant Nuthatch preferred to feed on trunks and large branches of larger diameter pines and Fagaceae trees. Based on the estimated population size, AMAM is probably a globally significant locality for Giant Nuthatch and the only confirmed locality in Myanmar since 1992 but is threatened by agricultural expansion. More detailed understanding of the habitat requirements of this endangered species and an assessment of its distribution at the landscape-level, especially in Shan State, would increase the precision of global population estimates.

The Straw-headed Bulbul Pycnonotus zeylanicus is one of South-East Asia’s most threatened songbirds due to relentless demand for the regional cage-bird trade. The species was recently uplisted from ‘Endangered’ to ‘Critically Endangered’ only two years after its previous uplisting. Intriguingly, populations in highly urbanised Singapore appear relatively secure. However, the last Singaporean density estimates, derived from traditional census methods, were obtained nearly two decades ago in 2001. A recent population estimate in 2016 was derived from the census work in 2001 coupled with relative abundance indices from population trends. We thus performed systematic field surveys using the distance sampling method, estimating 573 ± 185 individuals nation-wide, with a break-down of 217 ± 81 on the main island of Singapore and 356 ± 104 birds on the satellite of Pulau Ubin. Taken together, the total population estimate reported here comprises 22.9–57.3% of the global wild population, underscoring the importance of Singapore as a stronghold for the species. In spite of its apparently secure status in Singapore, the species remains susceptible to local and foreign trapping pressures. Based on our assessment, we propose a number of local and regional conservation measures to ensure the continued survival of populations in Singapore.

Insular species, particularly birds, experience high levels of speciation and endemism. Similarly, island birds experience extreme levels of extinction. Based on a 2012 taxonomic assessment, historically there were four reed-warbler species in the Mariana Islands, the Guam Reed-warbler Acrocephalus luscinia (Guam), the Nightingale Reed-warbler Acrocephalus hiwae (Saipan and Alamagan), the Aguijuan Reed-warbler A. nijoi (Aguiguan or Aguijuan), and the Pagan Reed-warbler A. yamashinae (Pagan). Between 2008 and 2010 we surveyed for three of these species on Alamagan, Aguiguan, and Pagan. Our results indicate that reed-warblers are extinct on Aguiguan, likely extinct on Pagan, and only the Nightingale Reed-warbler on Alamagan and Saipan remains. We estimated the global population at between 1,019 and 6,356 birds (95% CI; mean estimate 3,688), which has declined by more than 1,000 birds since the first quantitative surveys were conducted in 1982, i.e. a 24% decline in 28 years. Camp et al. (2009) describe the status of the Nightingale Reed-warbler on Saipan, which has also declined. We estimated the Alamagan population to be between 428 and 1,762 birds in 2010 (mean estimate 946). Thus, the Alamagan population is ~25 % of the global population, and it has declined slightly since 2000. This decline was not significant but is concerning, especially given a similar decline on Saipan. Restoration and protection of tall-stature native and secondary forest could benefit the Alamagan population, as would similar conservation on Saipan that includes wetland habitat. After suitable restoration of forest and wetland habitats on Aguiguan, Guam and Pagan, individuals from Alamagan and Saipan could serve as founder populations. Careful consideration of the extent and habitat preference of individuals translocated to Tinian, where an unknown reed-warbler species previously occurred, is warranted.