We documented the consequences of large-scale habitat loss on a community of Galápagos native bird species on San Cristóbal island, based on point counts conducted between 2010 and 2017. Surprisingly, despite considerable habitat change and a variety of other threats, the landbirds of San Cristóbal have fared much better than on the neighbouring islands Floreana or Santa Cruz. While two species went extinct very soon after human colonisation, the majority have adapted well to subsequent vegetation change and habitat loss. The endemic San Cristóbal Mockingbird Mimus melanotis is more widespread than previously thought and its population seems to be stable since the 1980s. We thus propose a change in IUCN classification from ‘Endangered’ to ‘Near threatened’. We present evidence gained by interviewing locals which suggests that a small population of the Least Vermilion Flycatcher Pyrocephalus dubius, classified as ‘Extinct’ by BirdLife International, may have persisted until very recently. Although extensive searches in 2018 and 2019 were unsuccessful, the possibility remains that a few birds may have survived in remote parts of the island. Further searches that involve the general public and other interested parties are therefore deemed necessary.

The breeding areas of the Critically Endangered Slender-billed Curlew Numenius tenuirostris are all but unknown, with the only well-substantiated breeding records being from the Omsk province, western Siberia. The identification of any remaining breeding population is of the highest priority for the conservation of any remnant population. If it is extinct, the reliable identification of former breeding sites may help determine the causes of the species’ decline, in order to learn wider conservation lessons. We used stable isotope values in feather samples from juvenile Slender-billed Curlews to identify potential breeding areas. Modelled precipitation δ2H data were compared to feather samples of surrogate species from within the potential breeding range, to produce a calibration equation. Application of this calibration to samples from 35 Slender-billed Curlew museum skins suggested they could have originated from the steppes of northern Kazakhstan and part of southern Russia between 48°N and 56°N. The core of this area was around 50°N, some way to the south of the confirmed nesting sites in the forest steppes. Surveys for the species might be better targeted at the Kazakh steppes, rather than around the historically recognised nest sites of southern Russia which might have been atypical for the species. We consider whether agricultural expansion in this area may have contributed to declines of the Slender-billed Curlew population.

Tracking studies of seabirds have generally focused in identifying areas used for foraging, in the hope of highlighting regions of energy transfer which may be important for seabird and general ecosystem conservation and special management. However, some sea areas may serve functions other than providing nutritional resources, which may be equally relevant, particularly if used by large numbers of individuals. In this paper, based on a study of 4 breeding colonies in the Falkland Islands and on 314 individuals tracked, we show that virtually all (97.8%) black-browed albatrosses Thalassarche melanophris (BBA) bathe in the close vicinity of the colony, remaining in the area for nearly an hour, before departing on a foraging trip. This compares with only 20 to 40% of the individuals landing close to the colony at the end of a foraging trip. The observed utilization of marine areas by BBA in a radius of 1 to 5 km around the nesting colony is one order of magnitude higher than elsewhere, including foraging hotspots. Clearly, even long-range flying birds such as albatrosses can make an intensive use of the sea-surface in the immediate vicinity of the colonies, and therefore any threats to seabirds in these areas (disturbance, pollutants, collision with artificial structures and light attraction) can potentially have a major impact at the population level. As such, the close neighbourhood of seabird colonies are potentially highly sensitive areas, and this needs to be taken into account when carrying out risk assessments or during marine spatial planning exercises.

Historical and anecdotal data indicate that out of 14 original species of resident diurnal raptors, six have become extinct and two more are considered endangered in the middle Cauca Valley, Colombia. While the decline of several species is related to a drastic reduction of original habitats such as forests and wetlands, three open-habitat species have also suffered population declines. Possible causes include the recent expansion of intensive agriculture (at the expense of cattle-ranching areas), agrochemical pollution, hunting, and factors such as body size, the proximity of the valley to the upper altitudinal limit of most of the affected species, and the relative isolation of the valley from the Caribbean region and the savannas east of the Andes. The need for monitoring projects s i stressed for the vertebrate fauna, including those species considered common in open and disturbed habitats.

Informaciones históricas y anecdóticas indican que de una fauna original de 14 especies de aves rapaces diurnas residentes en el valle medio del rio Cauca, Colombia, se han extinguido seis especies y dos mas se consideran amenazadas. Mientras que la disminucion de algunas especies se relaciona con la drástica reductión de hábitats originales tales como bosques y humedales, tres especies propias de hábitats abiertos también se han visto afectadas. Se identifican como probables factores la expansión de la agricultura intensiva (a expensas de las areas previamente dedicadas a la ganaderia), la contaminatión por agroquimicos, los conflictos con los intereses humanos y ciertos factores como el tamano corporal, la proximidad del valle medio del Cauca al limite superior de distributión altitudinal de estas especies y el relativo aislamiento del valle con respecto de la región del Caribe y de las sabanas al oriente de los Andes. Se relieva la necesidad de establecer programas de monitoreo de las faunas de vertebrados, inclufdas las especies consideradas como comunes en hábitats abiertos y perturbados.

No published information is available on the foraging ecology and choice of feeding habitat of New Zealand’s rarest breeding bird: the New Zealand Fairy Tern (NZFT) Sternula nereis davisae. To address this gap, we conducted an assessment of the largest remaining breeding population at Mangawhai Harbour, Northland, New Zealand, during the chick-rearing period of the 2010/2011 breeding season. We combined visual tracking of birds with prey surveys and stable isotope analyses, and we present the first quantitative assessment of NZFT foraging. We recorded 405 foraging dives that show NZFT foraging habitat includes the water edges, shallow channels, and pools on the tidal flats of mangrove-lined (Avicennia marina var. resinifera) parts of the estuary; tidal pools on mud- and sandflats in the mid-estuary and lower harbour; the shallow margins of the dredged main channel in the lower harbour; the oxbow lagoons on the sand spit; and coastal shallows. Our study identifies the mangrove-lined highly tidal and shallow mid-estuary and the lagoon on the sand spit as foraging hotspots for the Mangawhai breeding population of the NZFT. The prey survey employed a seine-net sampling method at identified NZFT foraging sites and yielded 4,367 prey-sized fish of 11 species, two of which had not previously been reported in Mangawhai Harbour, as well as numerous shrimps. The most abundant fish were gobies of the genus Favonigobius. Our stable isotope results highlight gobies as the most important prey for NZFT chick rearing, also indicating that flounder Rhombosolea sp. contribute to NZFT diet. We raise the possibility that shrimps may also constitute a substantial diet component for NZFT, potentially providing up to 21% of diet mass for adult birds. While our results provide a first basis to understanding the feeding ecology of NZFT during their breeding season in order to facilitate conservation planning, further research is required to address inter-annual variation and to identify key foraging grounds for this Critically Endangered bird at other breeding sites.

Systematic bird observations were performed during autumn 2006 in the migration bottleneck area of Zeit Bay, Egypt (27.73°N, 33.51°E), situated on the coast of the Gulf of Suez, opposite southern Sinai. Owing to the strong northerly winds in that area, considerable pressure exists to construct wind farms. A total of 145,432 soaring birds, including 134,599 storks and 9,376 raptors over a period of 453.6 hours were observed between 20 August and 29 October by two teams working daily in two shifts. White Stork Ciconia ciconia and European Honey Buzzard Pernis apivorus were the most numerous species (91.4% and 5.7% respectively) of all soaring birds observed. As both species migrate early, relatively few birds were recorded passing through in October. A total of 57,179 soaring birds were observed within a range of 2.5 km from the observers, and of these 32,248 were flying at heights up to 200 m. Few individuals of the rapidly declining breeding populations of Egyptian Vulture Neophron percnotperus (‘Endangered’) and Lesser Kestrel Falco naumanni (‘Vulnerable’) passed (8 and 33 respectively). Pallid Harriers Circus macrourus (‘Near Threatened’) however, were more numerous (100) than at other migration sites along the East African-West Asian Flyway (Israel, southern tip of Sinai, Suez and Bab-el-Mandeb). Western Marsh Harrier Circus aeruginosus and Montagu’s Harrier Circus pygargus were also more numerous than at these sites. Some other large migrant species, observed at Suez, Bab el-Mandeb or in Israel, were seen only in small numbers or not at all at Zeit Bay in autumn. Among them, the Steppe Eagle Aquila nipalensis being the best known example of loop migration, entering Africa at Suez and Bab el-Mandeb, is for this reason not expected in autumn at Zeit Bay, while in spring it is a regular migrant. The number of Black Storks Ciconia nigra observed accounted for 4.8% of the flyway population, that of White Storks for 33.3%, Great White Pelicans Pelecanus onocrotalus for a further 3.5% and European Honey Buzzards for 0.8%. The extrapolation of the number of birds passing through the study area during the migration season, suggests that it was used by 92% of the White Stork, 12% of the Black Stork, 5% of the Great White Pelican, 4% of the European Honey Buzzard and 2% of the Pallid Harrier flyway populations in autumn 2006.

Fieldwork on the distribution, habitat preferences and status of birds was conducted in the Bikin River basin, northern Ussuriland, south-east Russia, during May–July 1992,1993,1995,1996 and 1997. The results of this survey combined with data collected during 1960–1990, show the area to be of high conservation priority and one of the most important for the conservation of Blakiston's Fish Owl Ketupa blakistoni, Chinese Merganser Mergus squamatus, Mandarin Duck Aix galericulata and Hooded Crane Grus monacha. This paper reports on all of the 13 threatened and near-threatened breeding species of northern Ussuriland, with special emphasis on their occurrence and status in the Bikin area. Three more species, included in the Red Data Book of Russia, are also briefly discussed. Maps show the distribution of the breeding sites of the species discussed. The establishment of a nature reserve in the lower Bikin area is suggested as the only way to conserve the virgin Manchurian-type habitats (wetlands and forests), and all 10 species of special conservation concern. Monitoring of the local populations of Blakiston's Fish Owl, Chinese Merganser and Mandarin Duck in the middle Bikin is required.

The Olrog’s Gull Larus atlanticus is an endemic and threatened species of the south-western Atlantic. Little is known about its movements during the non-breeding period. The objective of this study was to analyse the migration of the species by tracking adults from Bahía San Blas (Buenos Aires province, Argentina) with geolocators and using information of sightings of ringed gulls. Differences between males and females were evaluated using tracking data and ringed data were used to determine age differences. A single core area (kernel 50%) from 21 tracked birds was identified. This area included the study colony and also other breeding colonies located up to 300 km to the north. The range area (kernel 95%) included coastal areas up to 1,000 km from the colony. All sightings of ringed gulls (n = 41) occurred north of the breeding colony, however 12 adult individuals were sighted during the winter in its breeding grounds. Our results suggest the occurrence of partial migration behavior in Olrog’s Gull. The migration pattern reported here implies than during the non-breeding season, breeding and wintering areas away from the nesting grounds should be considered as one system in the design of conservation strategies for this regionally threatened gull.

Tetrao urogallus cantabricus is the most endangered capercaillie subspecies and unlike the others it inhabits deciduous forests in the Cantabrian Mountains (north-west Spain). Its southernmost distribution occurs in Mediterranean forests outside conservation areas where wind farm construction is increasing. We surveyed Cantabrian Capercaillie presence in a wintering site one year before and four years after wind farm construction. Sign abundance greatly decreased after wind farm construction indicating a likely negative effect on Cantabrian Capercaillie habitat use. According to the precautionary principle, in order to conserve Cantabrian Capercaillie, all its range should be legally protected to avoid further wind farm construction and human disturbance.

Group size and habitat use of Black-necked Storks Ephippiorhynchus asiaticus were studied over a 30-month period in an unprotected landscape with a mosaic of natural and manmade features in Etawah and Mainpuri districts, Uttar Pradesh, India. Group size was largely one or two and never more than a family of two adults and three young. Group size did not change with season or across habitat types. Black-necked Storks used habitats to different extents across years and seasons. Wetlands were preferred in all seasons and rice-paddies were preferred during the monsoon. The use of irrigation canals was consistent across seasons and was always in proportion to their availability. Irrigation canals and crop-fields, particularly flooded rice-fields, provided some additional habitat to Black-necked Storks, but catered to the population for a very small period of time. While some studies have demonstrated that flooded rice-fields are useful for wintering waterbird species, conversion of natural wetlands to crop-fields will not be advantageous to Black-necked Storks, and these habitats need to be preserved to conserve the species.

The globally threatened (‘Vulnerable’) Saunders's Gull Larus saundersi has a small, declining population occupying highly-threatened habitats mainly along the coasts of China, the Korean Peninsula and Japan. The availability of recent count data from key non-breeding regions has provided an important opportunity to re-estimate the species’ population size and this is now believed to be a minimum of 14,400 birds, which is more than 70% higher than the mid-point of the current estimated range (7,100–9,600). However the apparent population increase is almost certainly due to increased survey effort. It is likely that the population is continuing to decline given the significant threats to habitats and high human disturbance levels occurring across the species’ range. There are increasing opportunities for coordinated counts of Saunders's Gulls along the Chinese coastline and these data, combined with those being collected annually from other parts of the non-breeding range, should allow improved population estimates to be obtained and the generation of much-needed population trend information.

Bwindi Impenetrable Forest, south-west Uganda, supports 24 of 37 restricted-range bird species of the Albertine Rift Mountains Endemic Bird Area (EBA). In common with other montane forest fragments in the EBA, Bwindi's structure and ecology have been substantially modified by human activities, the impact of which on its birds is difficult to gauge in the absence of quantitative information on their habitat use and abundance. During October 1999, habitat associations of nine restricted-range species and of 12 species with which they were commonly associated, were measured at Ruhija, Bwindi Impenetrable Forest. Logistic regression analysis was used to determine the relationship between habitat, topography, altitude and species occurrence. Population densities of 19 species were estimated using distance sampling, at survey points visited between dawn and midday. Although the detection rate declined during the morning, observations made towards midday helped to improve precision, without lowering density estimates. Eight habitat and topographical features significantly associated with restricted-range species are described. Few of the features measured were significantly associated with more than one species, underlining the importance of maintaining a diverse forest structure. Two restricted-range species were among the commonest birds in the study area, while a further four species were at least as abundant as their more widespread congeners.

The Northern Silvery Grebe Podiceps juninensis is an aquatic bird species considered Vulnerable to extinction in Ecuador and Endangered in Colombia. Globally the species is considered Near Threatened. Herein we report recent changes in distribution and population trends for the subpopulation in the northern Andes (Ecuador, Colombia), which is small and isolated. The Northern Silvery Grebe has undergone two documented extirpations, and at least one colonisation event, over the last three decades. More than 90% of the subpopulation relies on two wetlands, La Mica and Colta lakes in Ecuador, with the latter facing an accelerated sedimentation process which jeopardizes the fate of the wetland, and the species, in the mid-term. The population of La Mica lost 80% of its birds in 2000 after the damming of the lake, but then remained stable over our census period (2004–2013). In contrast, the Colta population results from a recent colonisation in the early 2000s, and has experienced an exponential growth since then (annual population multiplication rate: 1.464). The growth of this population is so fast that it must include an important contribution of immigrants. The temporal coincidence between the drop in population size at lake La Mica and the colonisation of lake Colta suggests that the Colta population was founded by immigrants from La Mica. Finally, the absence of current reports of the species at wetlands in Colombia suggests that the species remains at very low numbers, bolstering the shrinkage in northern distribution.

The Javan Hawk-eagle Spizaetus bartelsi is endemic to the island of Java. Severe habitat fragmentation and small population size, aggravated by illegal hunting have put this rainforest species on the list of threatened bird species. Intensive searching since 1986 resulted in the discovery of a large number of localities additional to the historic ones. All known locality records of Javan Hawk-eagle have been scrutinized and are listed in the present paper. Confirmed post-1980 records are from 24 forest fragments of varying sizes: 10 (including 28 discrete localities) in west, seven (including 14 discrete localities) in central and seven (including 20 discrete localities) in east Java. The configuration of available habitat in forest clusters is evaluated. The co-existence with other threatened bird taxa, and the need for further field surveys and studies of the Javan Hawk-eagle are discussed.

Developing a standardized survey methodology to census and estimate the size of wintering populations is a main conservation priority for the endangered Little Bustard. We present a standard and repeatable methodology to census wintering Little Bustard populations at a regional scale, and the first statistically reliable population estimate of a Little Bustard wintering population in Spain. We carried out two surveys, in 2003 and 2004, using UTM 10 km × 10 km squares as census units, which were subjected to stratified sampling over the species' potential distribution range in the region of Madrid (Central Spain). Only the areas of potentially suitable habitat within squares of known winter presence of the species were considered. The species' winter distribution in Madrid was fairly constant between years, showing a fragmented pattern in three main nuclei. The number of Little Bustards observed was consistent between surveys (752 and 786 birds, respectively), with birds grouped in an average of 32 flocks (1 to 350 birds, mean = 27.9 birds). No between-winter differences in flock size were observed, although differences between sectors were significant. The highest densities were observed in the Tagus valley (mean density = 2.9 birds km−2, 293 birds), followed by north-eastern farmland (mean density = 0.6 bird km−2, 269 birds). The estimated size of the Little Bustard population wintering in the Madrid region was 1,051 (95% CI = 1,043–1,231). This calculation was based on recorded population density, measured as the number of birds per square kilometre, and considers the potential habitats available in each sector. We propose this methodology as adequate for surveying any Little Bustard wintering area, at both regional and smaller spatial scales. Survey results are consistent with previous tentative estimates for the region of Madrid, and with available information on Little Bustard movements. Sixty-five per cent of squares with Little Bustard presence were outside any protected area, which makes the wintering Little Bustard population of Madrid highly vulnerable to habitat disappearance and may affect the viability of breeding nuclei whose individuals winter in the region.

Chu Yang Sin Nature Reserve, Dak Lak Province, Vietnam, is within an area of high bird endemism and supports a number of globally threatened and restricted-range species. Data were collected on the bird communities of the Reserve and their habitat in 1995, to ascertain habitat associations of some of the endemic and threatened taxa. Birds were surveyed in circular plots around a recording point. Habitat associations were investigated using Discriminant Function analysis, and populations estimated using DISTANCE.

Seven restricted-range species and 38 restricted-range subspecies were recorded in the survey. The number of contacts with some of the endemic species was low, which limited the statistical investigation of the habitat require ments of these species. When analysis was possible, altitude was the most important of the factors measured determining species distributions, while measures of forest architecture seemed less important. The area appears to support important populations of several restricted-range taxa and, provided that protection and management of the protected area can be enhanced, it remains one of the most important areas for bird conservation in southern Vietnam. Some drawbacks of the techniques used in the survey are discussed.

This paper summarizes current knowledge and outlines future work on the breeding biology of Southern Ground Hornbill Bucorvus leadbeateri in Zimbabwe. All available records since 1900 were analysed, including casual reports by members of BirdLife Zimbabwe and published records. Estimates were made for the start and end of the breeding season, group sizes, clutch size and productivity levels, together with an assessment of preferred habitats and nest-tree species. There is a need for intensive fieldwork to determine aspects of breeding biology such as incubation and nestling periods. Particularly important for sound management and conservation strategies is relative breeding success in different land-tenure systems. The author has started work in a communal area 40 km south of Bulawayo city; land-use systems such as new resettlement areas, commercial farms and protected areas remain to be studied.

We studied bird community composition and abundance within four vegetation and disturbance categories located within selectively logged and unlogged forest in a Bolivian subtropical lowland forestry concession. The logged forest was subject to reduced-impact logging between 1 and 4 years prior to our study. The four categories were: 1) ‘gap’ points possessing natural or anthropogenic tree-fall gaps; 2) ‘target’ points with one of five commercial tree species of harvestable size; 3) ‘future’ points possessing a commercial tree below harvestable size and 4) ‘non-target’ points not possessing harvestable tree species. The bird community composition of logging gaps significantly differed from that found within natural tree-fall gaps in the unlogged forest P< 0.05. Species richness was higher in natural tree-fall gaps than in anthropogenic gaps. Furthermore, a higher proportion of disturbance sensitive species were associated with natural-tree fall gaps, whereas a higher proportion of disturbance tolerant species were associated with anthropogenic gaps. No significant difference was detected in the bird community composition for the other three vegetation categories surveyed. We discuss the conservation and silvicultural repercussions of these results.

The once ‘Critically Endangered’ Seychelles Magpie-robin was down to just 12 individuals in 1960 on one island of the granitic Seychelles. In 2015, due to intensive long-term management the population stands at around 280 birds on five islands, marking a significant success for this species. Translocations to the islands of Cousin and Cousine have led to population saturation and stability, a translocation to Denis Island has resulted in a continuing population increase and the founder population on Frégate Island is likewise increasing. The latest translocation to Aride Island in 2002 resulted in population increase then stability but is now showing a steep decline throughout 2014 into 2015. Reasons for this decline are yet unknown though disease, lack of recruitment, the impacts of social conflict and the possibility of genetic issues are discussed. This report summarises the history of management for this species, compiling all available published and unpublished information, to provide a comprehensive account of the Seychelles Magpie-robin recovery.

Translocations of threatened species play an increasingly important role in conservation management. However, few studies have examined what effects, if any, the translocation process itself (i.e. catching, handling, confining, transferring and releasing an animal into an unfamiliar environment) has on subsequent breeding success. Takahe Porphyrio hochstetteri living on offshore “predator-free” islands in New Zealand are a model system for examining such effects because pre-breeding birds have been frequently translocated between established island populations before they pair up and breed at 2-3 years of age. We postulated that “translocated” breeders (i.e. breeders that had been raised on another island) would delay first breeding attempts and/or have lower reproductive success compared with “resident” birds (i.e. bred on the same island that they were raised). The results indicated that translocated birds did not delay breeding and had similar mean hatching and fledging success as resident pairs in their first breeding season and subsequent seasons combined. The results suggest that at least for large or long-lived birds such as Takahe, the effects of any stress from the translocation itself, or the release into an unfamiliar environment, might be either short-lived or not significant enough to hinder subsequent breeding success. We recommend that further research be carried out on other species to determine the baseline effects, if any, of translocations, so that they can be taken into account when considering other determinants of translocation success such as habitat suitability, number of individuals and timing of releases.