Birds are often used as ecological indicators because they are widely distributed across diverse habitats and display distinct behavioural responses to environmental changes. The Endangered Grey Crowned Crane Balearica regulorum is regarded as a flagship species of Africa’s wetland and grassland habitats, both of which are undergoing substantial transformation to alternative land uses. The delayed reproductive strategies and habitat specialisation of this crane species makes them more vulnerable to extinction, but this risk is further compounded by data paucity. We employed traditional and contemporary survey methods to collect breeding metrics to calculate stage transition probabilities (i.e. egg–hatchling, hatchling–juvenile) and to identify possible macro-environmental factors that either promote or hinder their reproductive output in a key agricultural area in KwaZulu-Natal, South Africa. We found that Grey Crowned Cranes have a low hatching rate of 38.4% (95% confidence interval 29.3–48.4%) and show that this low hatching rate is exacerbated under high rainfall intensity. Multivariate analyses and multi-model inference revealed that successful nest-sites were generally associated with larger open water-bodies, greater distances from shore, and increased proximity to secondary roads, buildings, and natural grasslands. Although increased agricultural activities might promote greater foraging opportunities, the overall breeding outcomes of this species were poor in this key agricultural region. Our findings stress the urgent need for further fine-scale data collection and monitoring activities to better inform conservation strategies for this species. We also encourage future studies to focus on aspects affecting Grey Crowned Crane breeding in regions where proximity to human activities is inevitable.

We investigated Eurasian Skylark Alauda arvensis avoidance of powerlines and their pylons by assessing the spatial distribution of Skylark territories. We mapped territory centres in a central German agricultural landscape during 2020 and used Bayesian logistic regression models to test if distances from powerlines and pylons are predictive of the presence of territories. We also tested other possible predictors, namely, nearest distances from roads, vertical structures, wind energy plants, settlements, as well as the nearest pylon type and vegetation. Distances from the nearest road and settlement were positively correlated with the probability of territory occurrence. However, distance from powerlines and pylons were not significant predictors. Skylarks were also more likely to establish territories in areas where winter grain is present. We conclude that powerlines are unlikely to lead to significant habitat reduction for the Skylark that would impact local populations. We can, however, confirm avoidance behaviour towards roads and settlements, as well as a preference for areas with winter grain because the crop’s growth period coincides with the start of the breeding season, initially providing vegetation of a suitable height and coverage.

Andean Condor Vultur gryphus populations are particularly low in the northern Andes. The species is considered nearly eradicated from Venezuela and listed as “Endangered” in Ecuador and “Critically Endangered” in Colombia. Even though it is severely endangered, the size of the Colombian condor population remains unknown. Using a citizen science-based approach, we conducted the first Andean Condor count for Colombia with the help of 207 observers at 84 simultaneous observation points. We used N-mixture models for spatially replicated counts to estimate the condor population. The total number of condors recorded simultaneously was 63 individuals, and we estimated a population size of 175–269 individuals using a maximum likelihood approach and 165–222 and 172–229 for the two best models using the Bayesian approach. Adults were observed more frequently than juveniles (1:0.43), a common pattern among raptors related to the higher mortality rates of immature birds, which is a prominent conservation concern due to the status of the species and the threats it currently faces throughout the northern Andes. Our citizen science-based study made it possible to gather, for the first time in Colombia, consolidated information on the status of the Andean Condor population using a standardised methodology to provide a reference for future counts and conservation actions, both at the national level and throughout the geographical range of the species.

Obligate avian scavengers, such as the “Critically Endangered” California Condor Gymnogyps californianus, face significant threats from human activities and environmental changes. This study examines the home range and presence of reintroduced California Condors in a protected area in Baja California, Mexico, focusing on the influences of seasonality, biological factors, and food supplementation. Using spatial data collected over 12 months with telemetry equipment, we analysed condor movements within and beyond the boundaries of the Parque Nacional Sierra de San Pedro Mártir. Our findings reveal that condors spend over half their time within the protected area, with an increased presence during winter months. Supplementary feeding programmes significantly increased condor presence within the park, particularly in spring and summer. Home range analyses showed that season significantly influenced home range sizes, with smaller ranges observed during winter compared with other seasons. Additionally, male condors had larger home ranges than females during spring, but no significant sex differences were observed in other seasons. Age did not have a significant effect on home range size. This study emphasises the importance of protected areas and supplementary feeding programmes in condor conservation, highlighting the necessity of continuous monitoring and management to help support this iconic species.

The Santa Marta Sabrewing Campylopterus phainopeplus is listed as a “Critically Endangered” hummingbird endemic to the Sierra Nevada de Santa Marta (SNSM) in Colombia. Prior to 2022, there were only three documented sightings of the sabrewing since it was described in 1879, including only one record between 1946 and 2022. As a result, this “lost” species has long been one of the most poorly known birds in Colombia. We located a resident population of Santa Marta Sabrewing along the Guatapurí River near the Chemesquemena and Guatapurí villages in July 2022, and at its type locality, San José, in January 2023. Based on historical data and newly collected field observations, we assess the species’ status and describe aspects of its natural history and ecology. Our review indicates that the species has been frequently misidentified in the past, and that to date, documented evidence of its presence is limited to four localities, all of them restricted to the south-eastern slope of the SNSM, along the mid Guatapurí River basin. Consequently, this bird appears to represent a case of microendemism. This species is likely to remain listed as Critically Endangered until conclusive evidence suggests otherwise. Field observations indicate that the species is highly associated with watercourses, where males hold year-round territories and form leks. We obtained records of males in mid-elevation habitats (1,150–1,850 m) for 16 consecutive months between July 2022 and October 2023, suggesting that the species might not be an elevational migrant, as previously speculated. More information is needed to understand the species’ ecology so that effective conservation actions can be designed in collaboration with the indigenous communities with which the species coexists.

We review the conservation status of two small rail species breeding in the Galápagos Islands: the endemic Galápagos Rail Laterallus spilonota and the native Paint-billed Crake Neocrex erythrops, widely distributed on the South American mainland. Using distance sampling with point counts, we estimated population sizes across islands with suitable habitat from 2015 to 2025. In 2022, we reassessed long-term trends for the Galápagos Rail on Santa Cruz Island, following the monitoring protocol used in earlier censuses (1986, 2000, 2007). We estimated the Galápagos Rail population at 32,300 pairs across seven islands, including a small, newly recorded breeding population on Pinzón and Floreana, where we rediscovered the rail in 2025. Additional breeding populations of unknown size exist in the humid zones of the two northern volcanoes of Isabela and on adjacent Fernandina. The largest population, on Santiago (22,400 pairs), has recovered remarkably over 40 years since goats and other herbivores were eradicated. We found the Galápagos Rail predominantly in the humid highlands, although a few pairs were recorded in the mangrove forests of Isabela Island. The species is absent from San Cristóbal Island. On Santa Cruz it showed a clear increase between 2007 and 2022. The Paint-billed Crake breeds on the four inhabited islands (Floreana, Isabela, San Cristóbal, and Santa Cruz), with at least 6,300 pairs. It was mainly found in grasslands and open woodlands within agricultural areas at lower altitude than the Galápagos Rail, resulting in minimal range overlap. Its population and range have expanded, especially on Santa Cruz. The significantly higher recent population estimate for the Galápagos Rail compared with past estimates, along with positive trends on at least three islands, warrants reclassifying the species IUCN Red List status from “Vulnerable” to “Near Threatened”.

A previously unknown raptor migration hot spot has been identified in southern Greece. During the post-breeding migration of 2024, a total of 11,790 individuals were recorded in 15 days, including 11,606 European Honey Buzzards Pernis apivorus. GPS tracking data from Finnish and Hungarian populations further highlight the site’s significance, suggesting that it could become the third migration hot spot for the species in the Mediterranean, alongside the Straits of Gibraltar and Messina. Plans to develop a wind farm in the area raise concerns due to its crucial role in the beginning of the long sea crossing to Libya.

The 13 species of hornbills occurring in Indonesia have been studied to varying degrees, but a comprehensive identification of knowledge gaps is still lacking. We conducted a systematic review of the literature to identify the species and topics that require further investigation. We searched the literature using ScienceDirect, Google Scholar, Neliti, ResearchGate, and the Google search engine for all publications from 1970 to 2023. Publications were grouped under 15 conservation and ecological topics related to hornbills. Our review included 183 publications, comprising journal articles (56.3%), theses/dissertations (23.5%), conference papers (18.6%), and small portions of books and book sections (1.6%). Almost all the literature (72%) had been published after 2013, while the remaining (28%) was published before this period. The need for further studies across all research topics was identified for several species, including the Sumba Hornbill Rhyticeros everetti, Sulawesi Hornbill Rhabdotorrhinus exharratus, and Papuan Hornbill Rhyticeros plicatus. We also underscore the need for investigation into seed dispersal, ecotourism, and research methods across all hornbill species. Enhancing research and drawing public attention to Indonesia’s hornbills should increase their popularity and may serve to increase financial resources. This is the first systematic review of hornbill research for Indonesia and provides important information to determine future hornbill studies in the country.

Knowledge of the status of ecosystems is vital to help develop and implement conservation strategies. This is particularly relevant to the Arctic where the need for biodiversity conservation and monitoring has long been recognised, but where issues of local capacity and logistic barriers make surveys challenging. This paper demonstrates how long-term monitoring programmes outside the Arctic can contribute to developing composite trend indicators, using monitoring of annual abundance and population-level reproduction of species of migratory Arctic-breeding waterbirds on their temperate non-breeding areas. Using data from the UK and the Netherlands, countries with year-round waterbird monitoring schemes and supporting relevant shares of Arctic-breeding populations of waterbirds, we present example multi-species abundance and productivity indicators related to the migratory pathways used by different biogeographical populations of Arctic-breeding wildfowl and wader species in the East Atlantic Flyway. These composite trend indicators show that long-term increases in population size have slowed markedly in recent years and in several cases show declines over, at least, the last decade. These results constitute proof of concept. Some other non-Arctic countries located on the flyways of Arctic-breeding waterbirds also annually monitor abundance and breeding success, and we advocate that future development of “Arctic waterbird indicators” should be as inclusive of data as possible to derive the most robust outputs and help account for effects of current changes in non-breeding waterbird distributions. The incorporation of non-Arctic datasets into assessments of the status of Arctic biodiversity is recognised as highly desirable, because logistic constraints in monitoring within the Arctic region limit effective population-scale monitoring there, in effect enabling “monitoring at a distance”.

Newly elevated to species rank, the Bahama Nuthatch Sitta insularis is or was a bark- and twig-gleaning insectivore only known in life from the pine forests of Grand Bahama in the Bahamas archipelago. It became increasingly difficult to find in the past 50 years, seemingly in part in response to multiple hurricanes in this century. In spring (June–April) 2018, when it was still known to be extant, we divided the island into seven sections and carried out point count transects with playback and measured habitat variables at 464 locations in pine forest across Grand Bahama. We made only six observations at six locations, all in the region of Lucayan North and each involving a single nuthatch (possibly all the same individual). Fourteen count points were within 500 m of the six locations, and tree size at these sites was greater in height and girth than at sites with no observations and indeed than at other sites within Lucayan North. Count points within 500 m of nuthatch records in 2004–2018 had larger trees and more snags than survey points over 500 m away from previous detections, while count points within 500 m of our 2018 nuthatch records tallied more snags than did those within 500 m of the 2004–2007 records. Declines in habitat quality, habitat extent, nesting substrate, and food availability (driven by logging, attritional island development, and the direct and indirect effects of hurricanes), plus speculated increases in populations of invasive predators/competitors and in major mortality events (hurricanes, increasing in force and frequency with climate change), are suspected to be the ultimate causes of the decline of the nuthatch, with Hurricanes Matthew and Dorian the proximate causes of its evident extinction in 2019.

Agricultural intensification has profoundly transformed Europe’s landscapes, driving widespread declines in farmland bird populations. Among the most pressing threats is the loss of meadows, either through conversion to arable land as a result of intensification, or through agropastoral abandonment leading to shrub encroachment. Although farmland bird populations in Central and Eastern Europe have historically declined more slowly than in other regions, recent evidence shows that even once-common species are now in decline. This highlights the urgent need to quantify these trends and identify their underlying drivers. In this study, we investigate habitat preferences and factors underlying the severe, over 30-year decline of Red-backed Shrike Lanius collurio, an iconic farmland species and key bioindicator of grassland biodiversity. Our research focused on a 440-ha alluvial floodplain in Slovenia’s Sub-Pannonian region, a site considered a national stronghold for the species. Territory surveys were conducted intermittently from 1992 to 2025, with detailed habitat mapping available from 2004 to 2022. Consistent with previous studies, our results indicated that breeding Red-backed Shrikes primarily occupied ecotonal habitats marked by extensive meadow cover, moderate shrub density, and high habitat heterogeneity. Alarmingly, between 1992 and 2025, the population declined by 92.44%, decreasing from 172 territories to just 13. The steep decline observed was likely driven by agricultural intensification, persisting under the Common Agricultural Policy (CAP), with conversion of meadows into arable land and the loss of traditional management leading to shrub encroachment. The latter emerged as the strongest predictor of population decline in the most recent years. Our findings emphasise the urgent need to protect, manage, and restore meadows to prevent further biodiversity loss. Considering the relatively better historical status of farmland bird populations in Central and Eastern Europe compared with their Western European counterparts, this worrying trend indicates that similar declines are likely widespread, highlighting the need for immediate research and targeted conservation efforts.

Poisonous birds are rare but on New Guinea, including Indonesia’s easternmost provinces, no less than nine poisonous species, eight pitohuis and one species of ifrita, are found. Pitohuis when handled can cause sneezing with numbness and burning of nasal tissue and nausea in humans. In the bird markets of western Indonesia novelty birds are traded at a premium and overexploitation of popular songbirds leads traders to find replacement species to meet demand. We conducted over 800 surveys in the bird markets of Sumatra, Java, Bali, Lombok, and Sulawesi between 1994 and 2023 and from 2015 onwards we assessed the online trade in pitohuis and Blue-capped Ifrit Ifrita kowaldi. We identified the species, recorded their prices and location, and the date when the birds were offered for sale. We analysed temporal trends, volumes, prices, and geographical origin of the sellers. Between 1994 and 2014 we did not encounter a single pitohui in the Indonesian bird markets. In the following years we recorded 113 pitohuis in 12 bird markets and we recorded 199 pitohuis for sale online; 248 were variable pitohuis and 54 were Hooded Pitohui Pitohui dichrous. No ifritas were recorded. Most pitohuis were recorded in eastern Java and Bali. Prices differed between eastern Java (mean of US$93) and western Java and Bali (US$185), possibly suggesting pitohuis arrive from West Papua in eastern Java and from there make their way to the outer markets. Pitohuis are marketed as “Papuan Straw-headed Bulbuls”; the Straw-headed Bulbul Pycnonotus zeylanicus is a very popular and expensive songbird from Southeast Asia, including western Indonesia, that has become rare both in the wild and in the markets due to overexploitation. Discussions about pitohuis on online forums rarely mention “poisonous” but when it is mentioned traders dismiss this as something not to worry about and they claim it to be dietary-dependent. Poisonous pitohuis are novelty, as well as master, birds in Indonesia, where they are marketed for their song ignoring any negative side-effects of them being poisonous. The trade in novelty species, when detected early, does allow for the authorities to intervene in a timely manner to ensure that this trade does not impede their conservation.

The global population and status of Snowy Owls Bubo scandiacus are particularly challenging to assess because individuals are irruptive and nomadic, and the breeding range is restricted to the remote circumpolar Arctic tundra. The International Union for Conservation of Nature (IUCN) uplisted the Snowy Owl to “Vulnerable” in 2017 because the suggested population estimates appeared considerably lower than historical estimates, and it recommended actions to clarify the population size, structure, and trends. Here we present a broad review and status assessment, an effort led by the International Snowy Owl Working Group (ISOWG) and researchers from around the world, to estimate population trends and the current global status of the Snowy Owl. We use long-term breeding data, genetic studies, satellite-GPS tracking, and survival estimates to assess current population trends at several monitoring sites in the Arctic and we review the ecology and threats throughout the Snowy Owl range. An assessment of the available data suggests that current estimates of a worldwide population of 14,000–28,000 breeding adults are plausible. Our assessment of population trends at five long-term monitoring sites suggests that breeding populations of Snowy Owls in the Arctic have decreased by more than 30% over the past three generations and the species should continue to be categorised as Vulnerable under the IUCN Red List Criterion A2. We offer research recommendations to improve our understanding of Snowy Owl biology and future population assessments in a changing world.