In addition to protecting species, conservation also includes the maintenance of evolutionary processes, but this aspect is often overlooked. Nesospiza buntings provide a good case study of the need to conserve evolutionary processes. They are endemic to the South Atlantic Tristan da Cunha archipelago, and traditionally have been treated as two species, with each having different subspecies on Nightingale and Inaccessible Islands. Both species are listed as Vulnerable because of their small ranges (<20 km2) and the threat posed by the possible introduction of alien organisms such as mice or rats. The two species differ markedly in size, especially bill size, related to dietary differences. However, recent research suggests that morphological diversity evolved independently on Nightingale and Inaccessible Islands, necessitating a revision of the taxonomy within the genus. I recommend that five taxa be recognized, with two endemic to Nightingale and three to Inaccessible Island. N. wilkinsi and N. questi on Nightingale are well-defined species, but there is considerable hybridization between taxa on Inaccessible Island. These three taxa may be incipient species, but are perhaps best treated as subspecies: N. acunhae acunhae, N. a. dunnei and N. a. fraseri (nom. nov.). All three species qualify as threatened, with N. acunhae and N. questi Vulnerable and N. wilkinsi Endangered. With fewer than 200 individuals, N. wilkinsi has one of the smallest natural populations of any bird. A reassessment of its population size is a conservation priority, following the 2001 storm that damaged many Phylica trees on Nightingale Island. Improved biosecurity quarantine measures are also needed for Nightingale Island. Care should be taken not to disrupt the natural processes occurring among bunting taxa on Inaccessible Island.

The western Angola Endemic Bird Area has 14 range-restricted species. Little is known about the conservation status of the region's birds due to the civil war that has raged in Angola for the last 27 years. The greatest diversity of restricted-range species is found in Cuanza Sul province, and given the uncertainty about their current status, many of these species are listed as Threatened. In this paper we report the first significant ornithological visits to the Gabela region since 1974. We visited an extensive scarp forest patch at Kumbira Primero, near Conda, as well as smaller forest areas along the Sumbe–Gabela and Sumbe–Seles roads. Most of the threatened species were relocated, including several species not seen since the 1970s. Gabela Bush-shrike Laniarius amboimensis was common and Monteiro's Bush-shrike Malaconotus monteiri was fairly common in degraded secondary forest, old coffee plantations and primary forest at Kumbira. Pulitzer's Longbill Macrosphenus pulitzeri was fairly common at higher elevations at Kumbira as well as in the dense understorey of secondary forest west of Seles. Gabela Akalat Sheppardia gabela was less common, with only three birds found at Kumbira and one near Seles, but may have been overlooked. Only one group of eight Gabela Helmet-shrike Prionops gabela was recorded, in open woodland at the base of the scarp between Kumbira and Seles. Angola Cave-chat Xenocopsychus ansorgei was found on the rocky slopes above the forest at Kumbira. We describe the first sound recordings for five threatened species, which will help future systematic surveys of the region's forests. Vocal evidence confirms the close relationship between Gabela Bush-shrike and Lühder's Bush-shrike L. luehderi. The most pressing need is to assess the extent of remaining forests, map the distribution of key species of conservation concern, and then draft a strategy to conserve key habitat blocks.

The biggest and best-known population of Brazilian Merganser Mergus octosetaceus occurs in the region of Serra da Canastra National Park, Minas Gerais, Brazil. However, prior to our study it had been recorded in only six sites in the park and its buffer zone. In 2001 and 2002 we surveyed the region to confirm the occurrence of the Brazilian Merganser in different areas within and outside the park. Samples were taken by walking along the banks of the watercourses, using tape-recording playback. We sampled 49 stretches of streams, and observed Brazilian Mergansers in nine localities, totalling 29 sightings. Taking into consideration the reports by biologists who participated in the fieldwork for the review of the park's management plan, the guaranteed reports of the occurrence of the species from local people, and the sites where its occurrence is judged to be very likely, we believe there are at least 81 individuals in the areas sampled. We point out that the absence of records in an area does not mean the absence of the species. Indeed, the presence of the Brazilian Merganser was confirmed, after the end of our field studies, in some stretches where we indicated its occurrence as very likely but had failed to detect it during the sampling. All anthropogenic activities that influence the quality and integrity of the rivers and their banks are a potential threat to Mergus octosetaceus. Efforts to preserve the species entail the conservation of its habitats, which comprise important watercourses and the surrounding natural vegetation.

The Grand Comoro Scops Owl Otus pauliani, confined to forest on Mount Karthala on Grand Comoro, Indian Ocean, is a distinct species based on the evidence of its plumage and voice. In November 1989 studies of territorial calling birds at night revealed its presence between 1,000 and 1,900 m on the north, west and south flanks of the volcano, on which there exists some 10,000 ha of suitable habitat. As territory sizes may be only 5 ha, the population could well be over 1,000 pairs but, although this is encouraging, there remains a long-term threat from forest loss through habitat fragmentation (fires, logging) and the spread of the Indian Myna Acridotheres tristis.

The global population of the Critically Endangered Raso Lark Alauda razae was estimated in January 2003 at 93–103 birds and in November 2003 at 76–87 birds. Of these, only 25–35% were females. Counts were based on observations of individually colour-ringed and measured birds. Birds were not breeding during the January visit, and were concentrated in two small areas at opposite ends of the island of Raso. This distribution differed substantially from that recorded previously during the breeding season. Three different feeding strategies were apparent: flocking, aggregating around key resources and feeding singly or in pairs. Birds moving to new feeding areas immediately adopted the feeding strategy of other birds present. Birds were seen drinking seawater on several occasions. In November 2003, birds were breeding but nest survival was extremely low due to high rates of egg predation. No evidence was detected of introduced predators on Raso. However, a population of feral cats was found on nearby Santa Luzia, prohibiting natural colonization or deliberate introduction of Raso Lark to the island, despite much apparently suitable habitat there. Faecal analyses showed that these cats feed largely on skinks. Increased tourism development on neighbouring islands is identified as a potential threat to the species.

The United Nations Sustainable Development Goals aim to improve livelihoods and maintain functioning ecosystems, and include the provision of electricity and the prevention of desertification. We show that the pursuit of those two goals can lead to developments that put critical ecosystem functions at risk. Vultures are scavengers that provide sanitary ecosystem services, but their populations across Africa are declining due to poisoning, electrocution, and collision with power infrastructure. The extent to which the pursuit of sustainable development threatens vultures in Africa is unclear. We surveyed 227 km of powerlines in Ethiopia, which revealed bird mortality (0.15 vulture carcasses / km) at power infrastructure constructed under a National Electrification Programme to provide universal electricity access by 2025. We also interviewed 190 local pastoralists in 10 areas about livelihood challenges, which revealed that the bush Prosopis juliflora, which was originally introduced to prevent desertification but then invaded north-eastern Ethiopia, increased livestock predation and motivated the use of poison to control predators. Actions to increase universal access to electricity and to reduce desertification therefore have undesired side-effects that increase vulture mortality through electrocution and poisoning. To avoid negatively affecting local vulture populations and the services they provide, we urge governments to use infrastructure designs that minimise the risk of electrocution and assist pastoralists to protect their livestock and reduce the risk of poisoning to vultures and other wildlife.

The Atiu Swiftlet Aerodramus sawtelli is endemic to the Cook Island of Atiu and has an estimated total population of less than 400, rendering it one of the world’s most globally endangered bird species. Over a series of five visits to Atiu, we collected data on the distribution of foraging swiftlets on the island, and their foraging and echolocation behaviour. The bird favours forests, agriculturally developed areas such as croplands, and populated sections of the island (e.g. gardens) but avoids the dry, upraised coral ring (makatea) of Atiu. It appears able to readily exploit new insects after they have immigrated to Atiu and may act as a natural control agent on pest species (e.g. Xyleborus perforans and Atrichopogon jacobsoni). We reanalysed the swiftlets’ echolocation calls within one of their roost caves in conjunction with new recordings. The calls do not contain ultrasonic components and are uniquely single clicks compared to the echolocation vocalisations of other swiftlet species. The minimal impact of human disturbance on the remote nesting caves of this bird suggests that its numbers, although small, represent a stable population.

In conservation biology, population monitoring is a critical step, particularly for endangered groups, such as steppe birds in European agro-ecosystems. Long-term population monitoring allows for determination of species population trends and also provides insights into the relative roles that environmental variability and human activities have on priority species. Here, we compare the population trends of two sympatric, closely related farmland bird species, the Little Bustard Tetrax tetrax and Great Bustard Otis tarda, in a protected area of Central Spain, which is their main stronghold in Europe. Over 12 years of monitoring, the abundance of Little and Great Bustards shifted in opposite directions in our study area. Little Bustard abundance decreased significantly (both males [-56%], and harder-to-detect females [-55%]), while Great Bustard abundance increased significantly (1,800%). Future surveys should be more precise and frequent for Little Bustards to facilitate evaluation of their population status and trends. We recommend annual surveys in 2–3 important locations by region throughout the breeding range for Little Bustards, while for Great Bustard the current regional monitoring programmes would be sufficient.

Anian veterinarians have much expertise which can be usefully applied to in situ avian conservation programmes. Their knowledge can assist conservation biologists in many of the manipulations which they are currently applying to endangered wild birds in their natural range. Possibilities are outlined and illustrated by examples from various field programmes.

Saffron-cowled Blackbird Xanthopsar flavus is a globally threatened icterid of open areas of south-eastern South America. Several sources suggest that the species is declining throughout its range, mainly due to habitat destruction. Between December 1997 and December 1999 we studied a breeding population of X. flavus at the Banhado do Vinte-e-Cinco and Banhado da Mulata area, Rio Grande municipality, Rio Grande do Sul state, Brazil. This population, previously unreported for the state's coastal plain, numbers at least 60 individuals and seems confined to an area of c. 35 km2. The area is characterized by Cyperacaea-dominated peat marshes in comparatively higher terrain, covered with sandy, rolling fields. The species was recorded in all months (not necessarily of the same year) except March, and a marked irregularity in flock size was detected. During the non-breeding period, flock size averaged 12.7 individuals (S.D. = 11.7; range = 2-37; n = 11). During the 1997-1998 breeding season (December to January), mean flock size was 25.3 individuals (S.D. = 16.2; range = 16-60; n = 7), while in the 1998-1999 and 1999-2000 breeding seasons, 33 and 4 individuals were recorded respectively. No pronounced discrepancy was found in the size of the largest flocks recorded per season (from 20 to 37 individuals), suggesting that the population is sedentary and that it undertakes only local movements. A nesting colony occupying the same part of the marsh in two successive breeding seasons was composed of six breeding pairs in 1997-1998, with an estimated nesting success of 31.8-36.3% at fledgling time. The species is highly gregarious and sociable, foraging flocks frequently following individuals of Black-and-White Monjita Heteroxolmis dominicana and, to a lesser extent, Yellow-rumped Marshbird Pseudoleistes guirahuro and Brown-and-yellow Marshbird P. virescens. Although habitat loss has been indicated as the main factor for the species' decline, we suggest that habitat perturbation and modification may affect negatively recruitment rates in the species and, theoretically, its overall population size. Furthermore, the conservation of Rio Grande's peat marshes should be regarded a regional priority, in order to preserve threatened birds and a very unusual wetland type.

Understanding the particular nesting ecology of island endemic species represents the first step in identifying suitable micro-habitats and establishing efficient management programmes. This could become even more important when island bird assemblages are prone to invasion by ecologically similar species that may eventually cause niche compression or the extirpation of species already present on the island. In this study we describe the nesting ecology of both native and introduced landbird species of the Juan Fernández Islands and determine the extent to which native species could be negatively affected by alien competitors. A total of 119 nests belonging to the 11 resident landbird species were analysed. Landbirds exhibited a wide range of nesting habitat preferences on the different islands, covering different vegetation types, altitudes and ecosystems. By means of a cluster analysis we determined that competition between alien and endemic species apparently does not represent an important factor affecting resource use by endemic birds. Endemic landbirds preferred sites comparatively higher above the ground, with a greater slope and a larger level of shelter, than alien species. The introduced hummingbird, the Green-backed Firecrown Sephanoides sephaniodes, had different nesting preferences to the endemic Juan Fernandez Firecrown S. fernandensis, whereas the House Sparrow Passer domesticus selected nest sites located in populated areas, suggesting that both alien species may not be competing with endemic passerines for nest sites. However, urgent measures are necessary to reduce the potential predation risk on Juan Fernandez Firecrown nests by the alien Austral Thrush Turdus falcklandii.

The movement and migration pattern of the ‘Near Threatened’ Sooty Falcon Falco concolor is poorly known. Sooty Falcons breed on the islands of the Arabian Gulf after arriving from their non-breeding areas that are mainly in Madagascar. In the first satellite tracking of the species we fitted a 9.5 g Argos solar powered transmitter on an adult breeding Sooty Falcon off the western coast of Abu Dhabi in the United Arab Emirates. The bird successfully undertook autumn migration to Madagascar, a known wintering area for the species. We document the Sooty Falcon’s autumn migration route and stop-over sites. The adult Sooty Falcon initiated its migration at night and with tailwinds, and travelled mainly during daytime hours for 13 days over an inland route of more than 5,656 km. The three stop-over sites in East Africa were characterised by moderate to sparse shrub cover associated with potential sources of water. We discuss the migration pattern of the tracked bird in relation to importance of non-breeding areas for Sooty Falcons and recent declines in numbers in their breeding range.

The Critically Endangered Himalayan Quail Ophrysia superciliosa has not been reliably recorded since 1876. Recent searches of historical sites have failed to detect the species, but we estimate an extinction year of 2023 giving us reason to believe that the species may still be extant. Species distribution models can act as a guide for survey efforts, but the current land cover in the historical specimen record locations is unlikely to reflect Himalayan Quail habitat preferences due to extensive modifications. Thus, we investigate the use of two proxy species: Cheer Pheasant Catreus wallechi and Himalayan Monal Lophophorus impejanus that taken together are thought to have macro-habitat requirements that encapsulate those of the Himalayan Quail. After modelling climate and topography space for the Himalayan Quail and these proxy species we find the models for the proxy species have moderate overlap with that of the Himalayan Quail. Models improved with the incorporation of land cover data and when these were overlaid with the Himalayan Quail climate model, we were able to identify suitable areas to target surveys. Using a measure of search effort from recent observations of other galliformes, we identify 923 km2 of suitable habitat surrounding Mussoorie in Northern India that requires further surveys. We conclude with a list of five priority survey sites as a starting point.

As an island endemic, the Island Scrub-Jay's Aphelocoma insularis population status and conservation are of concern. In addition, because the Island Scrub-Jay is easily observed, it is an ideal candidate for monitoring the effects of management efforts on Santa Cruz Island, California. We used estimates of territory size in several different habitats occupied by the Island Scrub-Jay and the total area of these habitats on the island to develop an empirical estimate of the population size for this species. Our most conservative, and we feel most realistic, estimate for the Island Scrub-Jay breeding population is 7,000 individuals and for the non-breeding population 5,500 individuals, yielding a total population estimate of 12,500. Even though conservative, this estimate is larger than earlier estimates of 4,000 to 6,000 individuals. Even so, our data suggest no reason exists for immediate concern regarding the population viability of the Island Scrub-Jay and they provide a baseline for future estimates and comparisons. Most importantly, this population estimate can be used to monitor the influence on the Island Scrub-Jay of future island management efforts, especially regarding exotic tree species and feral pigs.

The Red-legged Kittiwake Rissa brevirostris is a small gull which is restricted to four breeding locations, all in the Bering Sea (Pribilof Islands, Bogoslof Island, Buldir Island, and the Commander Islands). In the mid-1970s, when the earliest counts were made at most sites, approximately 260,000 birds were present at breeding colonies. Subsequent counts indicated that populations at Bogoslof and Buldir had increased by the early 1990s. Data for the Commander Islands were inadequate to make strong conclusions about trends but there were no indications of substantial change between the 1970s and 1990s. In contrast, Red-legged Kittiwakes have declined in the Pribilof Islands by approximately 50% since the mid-1970s, a matter of concern because this island group once contained more than 80% of the world's population. Research is needed to determine causes for declines in Red-legged Kittiwakes and population monitoring should continue to provide a basis for conservation measures.

Alagoas Curassow Mitu mitu is considered extinct in the wild, having previously inhabited a small area in north-eastern Brazil that has since been replaced by sugar cane farms. Around 50 birds possessing morphological features of this species are still alive in captivity in Brazil, all being descendants from a breeding programme started in 1979, using offspring from a single male and two females captured from the wild. However, this captive population also includes some hybrids with the congeneric Razor-billed Curassow M. tuberosa and their descendants. Furthermore, the validity of Alagoas Curassow as a species is questionable. We used two molecular markers to study the validity of this taxon as a species, to detect potential hybrids present in the stock, and to estimate genetic variability among the remnant specimens. The analysis of 760 base pairs from mitochondrial cytochrome b and control region sequences revealed that at least three of the 20 birds analysed had sequences identical to those of Razor-billed Curassow. The other 17 birds presented sequences that diverged 2.6% from Razor-billed Curassow. Moreover, a sample from an Alagoas Curassow museum skin collected from the wild in 1951 had cytochrome b sequences identical to those of the 17 birds. These results confirm the Alagoas Curassow as a valid species. DNA fingerprinting profiles of the 20 descendants from the Alagoas Curassow breeding population showed that this group of birds is depauperate in genetic variability. There was an increase in genetic variability of birds born after 1990, attributed to the hybrid mating of Alagoas Curassow with Razor-billed Curassow. We suggest that birds born before 1990 should be handled separately from the others. However, if a decrease in chick harvest among birds of this group is detected due to inbreeding depression or ageing, cross-breeding between this group and the group of birds most closely related to it should be considered in order to enrich the progeny with the Alagoas Curassow genome.

The endemic Galapagos Martin Progne modesta is a rare species. Population sizes in the past are unknown, but the few reports available suggest that it has become rarer in some sites. To obtain a better understanding of its population status, a simultaneous survey was conducted in 2017 around the coastline of 14 islands and 23 islets resulting in sightings of only 26 individuals. A simultaneous survey on Sierra Negra volcano on Isabela Island added five more individuals. However, observations from early expeditions and expeditions since 2015 have shown that the volcanoes of Isabela Island are important feeding areas and probable breeding areas for the Galapagos Martin, but these were largely excluded from the survey in 2017 due to logistical reasons. Historical and recent nesting sites include Tagus Cove on Isabela Island and Daphne Major Island. During our 2017 count, three possible new nesting sites were discovered: Daphne Minor, Santiago and a small crater on Punta Cristóbal on southwestern Isabela Island. From 2015 to 2018, 15 nests were also observed on the cliff in Tagus Cove. Two accessible nests were collected and revealed the first records of Philornis downsi in Galapagos Martin nests. The impact of parasitism by P. downsi is unknown but potentially severe. Given the lack of general knowledge about the biology of this species and its apparent low population sizes, further studies are urgently needed.

Hen Harrier Circus cyaneus and Short-eared Owl Asio flammeus are open-country birds of prey with overlapping distributions. Although both species face similar conservation threats across their ranges, work to date has largely been undertaken at a national scale with few attempts to collate and assess factors relevant to their conservation at an international scale. Here we use an expert knowledge approach to evaluate the impact of conservation threats and the effectiveness of conservation strategies for each species across Europe. We report results of responses to a questionnaire from 23 Hen Harrier experts from nine countries and 12 Short-eared Owl experts from six countries. The majority of responses for both species reported declines in breeding numbers. The perceived impact of threats was broadly similar for both species: ecological factors (predation, extreme weather and prey availability), changes in land use (habitat loss and agricultural intensification) and indirect persecution (accidental nest destruction) were considered to be the greatest threats to breeding Hen Harrier and Short-eared Owl. Short-eared Owl experts also highlighted lack of knowledge and difficulties associated with monitoring as a major conservation challenge. Despite broad-scale similarities, geographical variation was also apparent in the perceived importance of conservation threats, with some threats (such as direct persecution, large-scale afforestation or habitat degradation) requiring country-specific actions. Implementation of different conservation strategies also varied between countries, with the designation of protected areas reported as the most widespread conservation strategy adopted, followed by species and habitat management. However, protected areas (including species-specific protected areas) were perceived to be less effective than active management of species and habitats. These findings highlight the overlap between the conservation requirements of these two species, and the need for collaborative international research and conservation approaches that prioritise pro-active conservation strategies subject to continued assessment and with specific conservation goals.

Distance sampling, line transects and radio-tracking have been used previously to estimate population abundances and movements of hornbills. We used a large dataset of audio recordings made over 10 years to estimate seasonal variation in abundance of three species: Black-casqued Hornbill Ceratogymna atrata, Yellow-casqued Hornbill C. elata and Brown-cheeked Hornbill Bycanistes cylindricus, in Taï National Park, Côte d'Ivoire. The latter two species are Near Threatened. Recordings of hornbill wing-beats were used to control for potential seasonal variation in call production. Yellow- and Black-casqued Hornbill calls were 10 times as abundant from July to February as they were from March to June. Brown-cheeked Hornbills showed a similar trend, but less pronounced. From these data we concluded that large numbers of Yellow- and Black-casqued Hornbills had left the Taï National Park during this period. The significance of these findings is discussed in relation to the fragmentation and regeneration of the Upper Guinea forests and the relatively small size of the remaining forest habitat in the region.

Les taux d'abondance et de mouvement des populations de calaos étaient auparavant estimés par un échantillonnage et des analyses sur le logiciel Distance, des transects linéaires et des repérages télémétriques. Nous avons eu recours è un grand ensemble d'enregistrements audio effectués sur plus de 10 ans afin d'estimer la variation saisonniàre de l'abondance de trois espàces rencontrées dans le Parc National de Taï, en Côte d'Ivoire : le Grand Calao è Casque Noir Ceratogymna atrata, le Grand Calao è Casque Jaune Ceratogymna elata et le Calao è Joues Brunes Bycanistes cylindricus. Ces deux derniàres espàces sont aujourd'hui considérées comme presque menacées. Nous avons procédé è des enregistrements de battements d'ailes pour tester une potentielle variation saisonniàre de la production des cris. Les cris des Grands Calaos è Casque Jaune et è Casque Noir étaient dix fois plus abondants entre juillet et février qu'entre mars et juin. En revanche, les Calaos è Joues Brunes n'ont présenté qu'une petite variation du taux d'abondance entre ces deux périodes. D'apràs ces données, nous avons conclu qu'un grand nombre de Calaos è Casque Jaune et è Casque Noir quittent le Parc National de Taï entre mars et juin. La signification de ces découvertes est discutée en tenant compte de la fragmentation et de la régénération des forêts de Haute Guinée ainsi que de la dimension relativement petite de l'habitat forestier subsistant dans cette région.

Green areas are key habitats for urban avifauna. Urban parks stand out from other anthropic habitats especially in providing trophic resources for many bird species. Consequently, modifications of these green zones can imply major changes in urban biodiversity. Potential pernicious urban remodelling is taking place in parks of eastern Spain because natural grass is being replaced with artificial grass to save water and to avoid management. This study aimed to determine whether remodelled parks with artificial grass harbour lower avian diversity (alpha, beta and gamma diversity) than traditional parks with natural grass. We surveyed 21 parks with artificial grass and 24 parks with natural grass in 18 towns of the Valencia Region in autumn 2020. In each park, we carried out 5-minute and 25-m radius point counts for determining bird species and their abundance. The effects of park area and grass type on alpha diversity (species richness, Shannon diversity index, Pielou’s Evenness and total abundance) were tested by means of GLMs. Differences in beta diversity and its components (nestedness and turnover) were also analyzed with the Bray-Curtis dissimilarity index. Gamma diversity was assessed by means of species accumulation curves. Finally, differences in community composition were tested by PERMANOVA and SIMPER tests. The parks with natural grass always harboured higher gamma diversity, species richness and abundance. Turnover was higher in parks with natural grass, whereas nestedness was higher in artificial grass parks. Differences in community composition were due mainly to abundance differences in common ground-feeding birds. We highlight that the trend of replacing natural by artificial grass in urban parks has harmful effects on urban bird communities and is a threat to bird conservation. Although artificial grass might save water, the effects on urban biodiversity should be carefully evaluated.