The Northern Bald Ibis (NBI) Geronticus eremita, is an ‘Endangered’ bird species of which only very few wild breeding colonies have survived along the Atlantic coast of south-west Morocco. This paper analyses ecological conditions of the 72 breeding sites of the NBI that have been known since 1900 in Morocco. Characterisation of breeding sites is based on physical criteria (elevation above sea level, geomorphology, mean annual precipitation and types of landscape) as well as land use, vegetation cover, infrastructure and types of settlement within three perimeters (0–1 km, > 1–5 km and > 5–10(20) km) using Google Earth satellite images. Statistical analyses of the number of breeding pairs, fledglings and rainfall during different quarters of the year from 1994 to 2016 in the two remaining breeding sites in Souss-Massa National Park and Tamri showed expected patterns as well as unexpected differences between the two localities. Based on our findings and indications in the literature, we suggest general and specific recommendations for potential future translocation projects of the NBI. Based on the analysis of the 28 breeding colonies existing after 1977, two elements emerge as the most important prerequisites: a low level of disturbances at the breeding sites and adequate feeding areas at a reasonable distance of 5–15 km.

Although the factors associated with adult sex ratio (ASR) skew in threatened species are rarely identified, ASRs of threatened species appear to be more male-skewed with increasing severity of threat. In this study we investigate whether the ASRs of species classified as threatened because of decline are significantly different from those threatened because of small range. Despite previous studies suggesting an association between male-skewed ASRs and population decline, our results show that ASRs may be more male-skewed in species classified as threatened because of small range. Although selection would be expected to purge dispersal genotypes from isolated populations, our finding could result from an imbalance between immigration and emigration rates of species with small ranges. Future research should examine rates of emigration and immigration in species with small global ranges.

The 10 km2 island of La Digue, Republic of Seychelles, western Indian Ocean supports the last viable population of the Critically Endangered Seychelles Black Paradise-flycatcher Terpsiphone corvina. Small populations recorded on adjacent islands since the 1980s appear to be ephemeral and not self-sustaining. We document the results of the first island-wide survey of the flycatcher on La Digue using the playback of conspecific calls at random points. Previous surveys were based largely on counting the number of singing males. The survey was conducted between April and August 2001 and confirmed (i) the current world population is at least 200 individuals (109-145 territories, 218-290 individuals) in a c. 4.4 km2 range, thus accurately quantifying the documented increase in flycatcher numbers since the late 1970s; (ii) territories were more widely distributed than previously recorded and not exclusively associated with coastal plateaux or freshwater bodies, contrary to previous descriptions; and (iii) distribution was determined largely by the presence of high canopy (native) broad-leaved tree species. The importance of canopy height to flycatchers was highlighted by the fact that localized loss of high canopy (native) forest (4%), in a 161 ha study area on the large western plateau, resulted in an equivalent reduction (4%) in the number of territories. In light of our findings we discuss the implications for conservation of the flycatcher on La Digue and its possible translocation.

This research evaluated the nesting habitat, nest-site preferences, and nest architecture of the critically endangered White-bellied Heron Ardea insignis in Bhutan. There are fewer than 60 wild birds left in the world, distributed in Bhutan, India, and Myanmar with fewer than five active breeding pairs in Bhutan. From 2003 to 2018, 20 successful and two unsuccessful nests were located from which at least 76 juveniles were expected to have fledged. The population in Bhutan has remained at 22–30 individuals for the last decade. Site-specific data were collected from 22 nests, and additional vegetation and environmental data were collected from 14 nests and random sites. We used 20-m diameter circular plots to evaluate the site preferences. Ground vegetation, litter and rock cover were evaluated using four 1-m2 quadrats in both nest and random sites. Nesting habitat was analysed to compare characteristics of nesting sites to random sites. Our results suggest that the White-bellied Heron builds a simple platform nest within average distance of 74 m from water bodies on the tallest isolated trees at an average height of 18.3 m on an elevated site with a clear overview of surroundings and are sensitive to even slight disturbance. Our results also suggest that the bird has a preference for an east-facing aspect at an average slope of approximately 40° between the altitudes of 400–1,450 m. Our observations also suggest that the bird has abandoned all nesting sites used prior to 2015, and the frequency of nest re-use has decreased. Protecting each nest site from hazards, avoiding disturbance, maintaining safe feeding habitats and flight routes are essential to ensure continued breeding in current sites and survival of this population. Further research to better understand the habitat requirements for the White-bellied Heron is vital.

An evaluation of the relative abundance of the Black Catbird Melanoptila glabrirostris was undertaken on Caye Caulker, an offshore island along the barrier reef of Belize, Central America. Although the species is locally abundant in part of the Sian Kaàn Biosphere Reserve in Mexico, the species is facing habitat fragmentation and loss due to development, both along the Mexican coastal areas and on the island habitats in Belize. The Caye Caulker population appears to be the largest in Belize. Transects of fixed radius point counts resulted in 15.5% and mist-netting resulted in 22.4% of all birds recorded being Black Catbirds. The Neotropical migrant Grey Catbird Dumetella carolinensis apparently shares the same habitat on Caye Caulker and comprised 11.2% of all birds netted. The netted Black Catbirds were noted to have substantial fat deposits. The habitat on Caye Caulker is facing probable fragmentation from recent accelerated land speculation and development of an airstrip.

The Hainan Hill-partridge Arborophila ardens is endemic to the island of Hainan, which lies off the south coast of China. Distinct subspecies of the Silver Pheasant Lophura nyethemera xvhiteheadi and Grey Peacock-pheasant Polyplectron bicalcaratum katsumatae are also endemic to the island. All three taxa are considered endangered and are very poorly known in the wild. Surveys of remaining patches of forest were undertaken between 1987 and 1994 during which local people were interviewed and some forest areas were visited. The hill-partridge was confirmed from three blocks of forest and reported from a further four. The Silver Pheasant was found in six areas of forest and probably occurs in all remaining patches of well-developed secondary and primary forest. The Grey Peacock-pheasant was recorded in five forests and reported from a further four. The hill-partridge was more restricted in its habitat use than the other two species, the latter using well-developed secondary forest in addition to primary forests. Provisional density estimates made at Ba Wang Ling National Nature Reserve were 6–8 Hainan Hill-partridges/km2, 7.5 Silver Pheasants/km2 and 3.75 Grey Peacock-pheasants/km2.

This paper documents the catastrophic decline of the ‘Critically Endangered’ Fatu Hiva Monarch Pomarea whitneyi since 2000 and presents population dynamics and conservation actions for the species between 2008 and 2017. The Fatu Hiva Monarch conservation programme has prevented the extinction of the species thus far. However, after an initial increase in the population size within the management area between 2008 and 2012, recruitment subsequently declined. Improvements in the method of trapping to control cats in 2016 and 2017 coincided with encouraging results in terms of juvenile monarch survival rates, although two adult birds disappeared during the same period. The initial hypothesis, that the population would recover once the main threat, black (or ship) rat Rates Rattus predation, was effectively controlled in the breeding territories, has not proved to be correct. An alternative hypothesis assumes that cat predation, mainly on young birds, is limiting monarch recovery. Control of feral cats has been undertaken since 2010, but the implementation of a new trapping method (leg-hold traps) combined with a significant increase in cat trapping effort, has coincided with an increase in the number of cats culled, as well as monarch post-fledging survival in 2016 and 2017. For the first time in the project, no mortality has been observed for monarch chicks, fledged juveniles or immature birds. If this alternative hypothesis holds, we would expect to recruit young birds into the monarch population in the next year or two. First, this will reduce the likelihood that the Fatu Hiva Monarch will become extinct and second, provide a source population to either repopulate the island following the eradication of rats and cats or to translocate birds to a rat and cat free island.

The marooning of populations on offshore islands can be used as a conservation technique for species threatened by introduced predators, but post-release breeding success is not always as high as expected. Following the release of Mauritius Fodies onto a partially restored islet of regenerating forest, supplementary food and control of nest parasites through the application of insecticide were used as precautionary measures to aid the establishment of a population. Nests were continuously monitored in the first three breeding seasons to inform future management decisions. The fodies built nests in taller, more mature vegetation and younger females were more likely to abandon nests before incubation started. Eggs were laid between July and February and nests made earlier in the season were more likely to fledge young. Treating nests with the insecticide carbaryl increased the probability of success, but the distance of the nest from the supplementary feeding aviaries had no effect. The number of young per female decreased each breeding season and nesting success was similar to that of fodies using exotic plantation trees on the mainland between 2002 and 2006. Future research using population models and adaptive management could lead to the withdrawal or reduction of support measures for the released population and/or the harvest of individuals to establish populations on other offshore islands.

The diet patterns and trophic relationships are poorly understood for most tropical owl species. We used stable isotopes of carbon (δ13C) and nitrogen (δ15N) in 24 feather samples of the rare, endemic, and ‘Near Threatened’ Bearded Screech-owl Megascops barbarus to determine the trophic level of their prey and evaluate whether diet patterns vary (1) among individuals, (2) spatially along the species's range in the highlands of Chiapas, Mexico, and (3) temporally during the short- and long-term. Our results indicated that there was diet variation among individuals during the period of feather growth and there was a high positive correlation between stable isotopes in body and rectrices. The stable isotopes showed significant temporal differences in δ15N signature values, but not in δ13C values, with no obviously interpretable temporal pattern. Spatially, values of δ13C and δ15N did not vary across all nine sampled locations. The observed lower δ13C values suggested that this owl lives in humid forests. More long-term studies and spatial dietary and prey analysis will be necessary to increase our understanding of how habitat conditions determine the distribution, abundance and quality of food for the Bearded Screech-owl.

We report on what appear to be increasing predation events on nesting Thick-billed Parrots Rhychopsitta pachyrhyncha. Thick-billed Parrots are classified as ‘Endangered’ and their seasonal breeding range is restricted to increasingly fragmented and degraded high elevation mixed conifer forest habitat within the Sierra Madre Occidental region of north-western Mexico. Predation of established breeding pairs has recently contributed to the ongoing decline of Thick-billed Parrot populations by removing mature birds with high reproductive value, which has associated consequences for future recruitment. We observed increasing predation events on nesting Thick-billed Parrots by bobcats Lynx rufus accompanied by kittens throughout the 2018–2019 breeding seasons, and we speculate that recent reductions in bobcat habitat have pushed them into new ranges where they are supplementing their diet with nontraditional prey items.

The expansion of wildlife trade on social media presents many challenges but also opportunities to gain insights into areas of trade where there is little recent data. West Africa has historically been a major source of wild birds in international trade but in 2007, the requirement for CITES (Convention on International Trade in Endangered Species of Wild Fauna and Flora) Parties to monitor a host of West-African species ended and there is little data regarding current trade. To address this gap, we surveyed trade-related posts created by known traders from 2016 to 2020 on a popular social-media platform to identify species composition, trade routes and potential conservation and biosecurity risks. We identified 427 social-media posts featuring a broad taxonomic diversity of birds, including 83 species from 26 avian families, including nine CITES-listed species, four listed in IUCN Threatened categories and 19 associated with alien introductions linked to bird trade. Disease risks were identified, with multiple species housed together in densely-stocked facilities and nine species recorded as posing a potential disease risk. Using novel analyses of post-engagement, we observed social-media posts facilitating connections with users across the globe. Trade-related engagement particularly came from countries in the Middle East and South Asia, notably India which has strong domestic restrictions on the importation of wild birds. Further research is needed to monitor the impact of trade from this region, as data regarding the population status and volume of trade in many observed species is largely absent.

The Rota White-eye, Zosterops rotensis, is a critically endangered species endemic to the island of Rota, in the Mariana Islands, western Micronesia. There has been a dramatic decline in both its population size and range over the past few decades. The population, estimated at approximately 1,000 individuals in 1999, is found exclusively in 300 ha of mature limestone forest, though nearby areas of mature limestone forest remain unoccupied. We compared the bird community, vegetation characteristics and foliage-invertebrate density in forest plot pairs with known high and low densities of Rota White-eyes. Discriminant function analysis suggested that certain vegetation characteristics were best at predicting whether a plot was high-density or low-density. High-density plots had more stems with 20–50 cm DBH, more foliage intercepts at 3–9 m, more epiphytes, greater total canopy cover and fewer overall plant species. This information is essential for the protection of the current habitat of the Rota White-eye and for future efforts in the protection and management of this species.

Seabirds are declining globally and are one of the most threatened groups of birds. To halt or reverse this decline they need protection both on land and at sea, requiring site-based conservation initiatives based on seabird abundance and diversity. The Important Bird and Biodiversity Area (IBA) programme is a method of identifying the most important places for birds based on globally agreed standardised criteria and thresholds. However, while great strides have been made identifying terrestrial sites, at-sea identification is lacking. The Chagos Archipelago, central Indian Ocean, supports four terrestrial IBAs (tIBAs) and two proposed marine IBAs (mIBAs). The mIBAs are seaward extensions to breeding colonies based on outdated information and, other types of mIBA have not been explored. Here, we review the proposed seaward extension mIBAs using up-to-date seabird status and distribution information and, use global positioning system (GPS) tracking from Red-footed Booby Sula sula – one of the most widely distributed breeding seabirds on the archipelago – to identify any pelagic mIBAs. We demonstrate that due to overlapping boundaries of seaward extension to breeding colony and pelagic areas of importance there is a single mIBA in the central Indian Ocean that lays entirely within the Chagos Archipelago Marine Protected Area (MPA). Covering 62,379 km2 it constitutes ~10% of the MPA and if designated, would become the 11th largest mIBA in the world and 4th largest in the Indian Ocean. Our research strengthens the evidence of the benefits of large-scale MPAs for the protection of marine predators and provides a scientific foundation stone for marine biodiversity hotspot research in the central Indian Ocean.

The Madagascar Red Owl, known from the eastern rainforest of central Madagascar by a few specimens collected in the nineteenth and early twentieth century and one sight record in 1973, was rediscovered in late July 1993 in north-eastern Madagascar. An adult bird, held in captivity for approximately one year, was located in the town of Andapa. According to the owner, the owl had been obtained south-west of Andapa, near the village of Antanamangotroka, in a forested area connected to the Réserve Spéciale d'Anjanaharibe-Sud, and at about 800 m above sea-level. This record expands the known geographic range of this species and provides the first documentation of its continued existence in over 20 years.

La Chouette de Soumagne, connue de la forêt pluviale orientale du Domaine du Centre de Madagascar à travers quelques spécimens collectés au 19ème siècle et début du 20ème siècle et d'aprés une observation en 1973, a été redécouverte à la fin du mois de juillet 1993 au nord-est de Madagascar. Un individu adulte, qui venait de passer plus d'un an en captivité, a été découvert dans la ville d'Andapa. D'après la personne qui détenait l'animal, la chouette avait été capturee au sud-ouest d'Andapa, pres du village d'Antanamangotroka, au sein d'une zone forestière connectée avec la Réserve Spéciale d'Anjanaharibe-Sud, à une altitude d'environ 800 m au-dessus du niveau de la mer. Cette nouvelle donnée constitue une expansion significative de l'aire de distribution de cette espèce et apporte la preuve de la survie de cette espèce endémique qui n'avait pas été observee depuis plus de 20 ans.

Observations of the Horned Curassow Pauxi unicomis in Amboro National Park, depto. Santa Cruz, Bolivia, allowed us to assess the status of a species whose habits in the wild were virtually unknown. Vocalizations, including call notes and the deep booming song, are described. Density was estimated by counting booming birds in the breeding season using a three-hide triangulation method. The study showed birds to be aggregated in one part of the study area. A nest of was found and the incubating female was observed for nine days: the individual incubated alone, left the nest at night, and returned at first light.

Observaciones de la Pava Copete de Piedra (Pava Crista Azul) Pauxi unicomis en el Parque Nacional Amboró, depto. Santa Cruz, Bolivia, nos permitió evaluar el estado de una especie cuyo comportamiento en el ambiente silvestre es prácticamente desconocido. Se describen vocalizaciones, que incluyen notas de llamada “call notes” y el profundo canto de estampida “deep booming song.” Se estimó la densidad de las aves por conteo de los sonidos de estampida “booming birds” durante la estacion reproductiva, usando un método de triangulación con tres puestos de observatión. Este estudio mostró que las aves se agregaban en una parte del área del estudio. Se encontró un nido de Pauxi unicomis y al hembra fue observada durante nueve dias durante la incubación; la hembra incubaba sóla, dejaba el nido por la noche y regresaba a las primeras horas del amanecer.

The Houbara Bustard is a winter visitor to the United Arab Emirates. Monitoring its population over large areas is difficult, due to the low density of the species and the nature of its habitat. We examined the possibility of using a network of desert rangers in the western region of the Abu Dhabi Emirate to monitor the population, timing of occurrence and distribution of Houbara Bustards in two consecutive winters. Houbara Bustards arrived in Abu Dhabi in September and moved inland towards the south of the country. The last birds were seen in March. Numbers ranged from 56 to 112 in 1994/1995 and 117 to 235 in 1995/1996. Houbara sightings were not evenly distributed within the region, with consistently higher numbers in sand-dune areas. This habitat is not optimal for Houbaras, where, in the past, they were less often encountered. The level of disturbance associated with more favourable habitats may be one reason why the birds are moving to more remote and inaccessible places. The use of a network of local rangers proved to be invaluable for gathering information on the low density Houbara population over a large area and was a very efficient way of monitoring the status of this endangered species.

The Blue Swallow Hirundo atrocaerulea is a globally threatened species endemic to sub-Saharan Africa. The total population breeding south of the Limpopo River (i.e. in South Africa and Swaziland) probably numbers around 100 pairs. A significant proportion of these birds breed in Swaziland, but to date little has been published on this population. Suitable breeding habitat has been reduced significantly in the country in recent decades, due mostly to afforestation with exotic timber plantations, with urbanization playing a lesser role. In Swaziland, breeding sites are restricted to grasslands above 1,200 m, but mostly above 1,300 m. Timing of egg laying is bimodal indicating double brooding. The number of nests initiated in a season is weakly correlated with rainfall in preceding months. Nests were built predominantly in disused antbear Orycteropus afer burrows, with smaller numbers in natural sinkholes. Mean clutch size was 2.80, and 61% of eggs laid resulted in fledged offspring. Mean productivity was 1.30 fledglings per pair per nest attempt. These figures suggest that breeding success is not currently being reduced in Swaziland. The minimum total population currently thought to be breeding in Swaziland is 10 pairs, but this is based on intensive studies of only part of the suitable range. It is recommended that a complete survey be conducted covering the entire range of the species in Swaziland.

The near-threatened Lilian’s Lovebird Agapornis lilianae is a small parrot endemic to the Zambezi basin in south-east Africa. The species has a fragmented distribution predominantly within mopane woodlands and is widely referred to as a mopane specialist. The harvesting of mopane trees for charcoal production and timber are having widespread impacts on this woodland habitat, raising concerns over its capacity to support biodiversity. This study aimed to understand the key drivers determining the occurrence of Lilian’s Lovebird in the mopane woodlands of Zambia, focusing particularly on aspects of woodland structure, including the size and density of trees. We used a MaxEnt species distribution model based on historical species occurrence data, to inform selection of 116 survey plots in the Luangwa, Luano and Zambezi valleys. Each plot was sampled for Lilian’s Lovebirds and woodland structure described. Occurrence of Lilian’s Lovebird was found to be positively associated with the size of mopane trees (both height and diameter at breast height) suggesting that large ‘cathedral’ mopane trees provide a key resource for the species and that conservation efforts should focus on the protection of sites containing large trees. No Lilian’s Lovebirds were recorded in areas where they previously occurred to the west of Lower Zambezi National Park, and there was an absence of ‘cathedral’ mopane habitat in this area.

The pressures for land use change have led to an increasing isolation of habitat remnants throughout the world. The goal of this study was to estimate the population size and density of some endemic and threatened species in a nature reserve in the Cerrado biome. One hundred and thirty four point transects were undertaken at the Estação Ecológica de Itirapina (EEI), one of the last natural grassland savannah remnants in São Paulo state, in the south-east of Brazil between September and December 2006 and densities estimated for seven species (four endemic to the Cerrado, one near-endemic and two grassland specialists). Neither species reached the minimum viable population size of 500-5000 individuals. Four species, White-banded Tanager, White-rumped Tanager, Black-throated Saltator and Sharp-tailed Tyrant have populations ranging from 112 to 248 individuals, while the other species have a low population (< 60 individuals). The mean densities of Sharp-tailed Tyrant and Cock-tailed Tyrant in the EEI grassland showed similar values to those observed in larger areas of the Cerrado, which may indicate that the EEI grassland area is well conserved. In spite of the restricted size of the EEI, small areas can maintain some endemic and threatened bird populations, thus contributing to local biodiversity and the ecological processes in the region. The capacity of fragments of Cerrado (~ 2,000 ha) to maintain populations of endemic and threatened bird species is unlikely to be effective in the long term.