Little is known about the contribution of different forest types to the beta-diversity, abundance and biomass of the avifauna in lowland Amazonia. This paper presents data on the large-bodied bird assemblages of adjacent upland (terra firme) and seasonally flooded (várzea and igapó) forests in the lower Rio Purús region of central-western Brazilian Amazonia. We focus our analysis on 23 large-bodied canopy and terrestrial bird species from 10 families, on the basis of 2,044 bird sightings obtained during line-transect censuses conducted over a two-year period. Large toucans comprised the most numerically abundant large birds in terra firme and igapó forests, whereas macaws were the most abundant in nutrient-rich várzea forests that were seasonally inundated by white-water. The aggregate population density of all bird species in terra firme forest was slightly higher than that in várzea forest. Igapó forest, which was seasonally inundated by black-water, sustained the lowest population densities. Terra firme and várzea forests differed considerably in species composition and abundance whereas igapó forest shared many species with both terra firme and várzea. Our results suggest that Amazonian floodplain forests play a major role in the persistence and community dynamics of the large-bodied forest birds.

Pouco se sabe sobre a contribuição de diferentes tipos de florestas aos padrões de beta-diversidade, abundância e biomassa da avifauna na região amazônica. Este artigo apresenta dados à respeito das aves de médio a grande porte em florestas de terra firme e florestas adjacentes sujeitas a inundação sazonal (várzea e igapó) na região do baixo Rio Purús da Amazonia centro-ocidental. Nossa análise, baseada num total de 2,044 observações obtidas durante censos ao longo de transectos, foi direcionada a 23 espécies de aves de médio a grande porte pertencentes a 10 famílias. As aves mais abundantes em florestas de terra firme e igapó foram os tucanos, e as araras as mais abundantes em florestas de várzea. A densidade de população agregada de todas as espécies na terra firme foi ligeiramente mais elevada do que na várzea. A floresta de igapó sustentaram as mais baixas densidades populacionais. Terra firme e várzea diferem consideravelmente na composição e abundância de espécies, visto que a avifauna do igapó é intermediária entre a da terra firme e a da várzea. Os resultados sugerem que as florestas inundáveis tem uma papel muito importante na manutenção das comunidades de aves de grande porte na Amazônia, e pricipalmente aquelas espécies que usam grandes mosaicos de floresta.

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.

We analyse the causes of mortality for the Bearded Vulture in Europe. Shooting (31%), intentional poisoning (26%), collision (18%) and unintentional poisoning (12%) were the most important causes of mortality. No differences were found between sexes or age classes (non-adults and adults) for any of the causes of death. When the four main categories of mortality were grouped in periods of 3 years from 1986 (coinciding with the species' reintroduction to the Alps) to 2006, mortality showed significant temporal variation. The results suggest that while the number of collision/electrocution deaths has remained stable or increased slightly, the number of cases of shooting has declined during the last 6 years, while at the same time intentional and unintentional poisonings have increased. We found substantial differences between causes of mortality recorded for birds located by chance (75% related to shootings and collisions with powerlines) and radio-tagged birds (86% related to intentional and unintentional poisoning), suggesting biases in methodology for monitoring mortality. The results suggest that human persecution continues to be the main factor contributing to unnatural mortality for European Bearded Vultures. Future management actions should concentrate on the creation of protocols for the collection of carcasses and detailed analyses to determine and mitigate anthropogenic sources of mortality.

Codfish Island is the southernmost breeding location for Cook's Petrel (Pterodroma cookii), endemic to the New Zealand archipelago. To provide a population estimate and indication of population growth following introduced predator eradications we conducted an island-wide survey of Codfish Island within two a priori defined strata. Plot surveys revealed only five burrows within forest habitats from 175 plots surveyed and the locations of these and other burrows observed incidentally were used to identify three key areas of Cook's Petrel breeding activity that were subsequently surveyed using line transects. Within these areas, 42 burrows were counted with burrow densities ranging from 0.0003 to 0.002 burrows m−2. Burrow densities in conjunction with the three-dimensional surface areas of the surveyed locations suggested a minimum of 6,194 ± 956 burrows present and equated to approximately 5,000 (95% CI 3,000–6,000) breeding pairs, using a burrow occupancy estimate of 80%. The Cook's Petrel population on Codfish Island appears to have increased markedly since Weka (Gallirallis australis ) and Pacific Rat (Rattus exulans) were eradicated in 1980 and 1998 and is consistent with a recent upwards revision of the species' world population size of approximately 1,300,000 (900,000–1,800,000) individuals. Revised population data, and ongoing protection of Cook's Petrel's major breeding sites may now qualify the species for a revised conservation status moving from Endangered to Vulnerable under IUCN criteria.

The global decrease of vulture populations has been attributed to several factors, such as food availability, poisoning, human disturbance, or habitat suitability. We studied the effect of factors that vary both spatially and temporally on the nest site distribution of the Griffon Vulture Gyps fulvus in northeast Portugal, and influence the population dynamics of these cliff-dwelling birds. Several demographic parameters were studied in the field, and the age structure of the population was determined. Additionally we investigated how food availability affected population fluctuations. The vulture population was most sensitive to juvenile mortality according to our model results. Our models showed that a decrease in the present food supply resulted in a decrease in vulture abundance and, moreover, negatively affected the spatial distribution of the species by decreasing the number of breeding pairs per colony. The total quantity of sheep and goat biomass, a greater distance to the nearest unpaved road, and the presence of Egyptian Vultures Neophron percnopterus at the breeding colonies showed a significant positive relationship to the numbers of Griffon Vulture breeding pairs. It is recommended that the available food supply in the most important foraging areas should be monitored and protected. Furthermore, to manage the community of cliff breeding raptors adequately, future research should identify and protect the most suitable breeding areas for each species. Human disturbance should be kept to a minimum by protecting breeding areas, especially in an area like Riba-Côa where species such as the Egyptian Vulture, Bonelli's Eagle Hieraaetus fasciatus and Griffon Vulture breed so close to each other.

Central America is a region of great avian diversity, and the highlands of Costa Rica and Panama are particularly rich in endemic bird species. Continuing deforestation has destroyed large parts of the birds' natural habitats in this region. The ability of birds to use non-forest habitats will ultimately determine their vulnerability to further deforestation, and knowledge of their habitat use is therefore essential in planning conservation strategies. We examined the effects of deforestation on the abundance of restricted-range bird species in the southern Costa Rican part of the Talamanca mountain range. We used line-transect distance sampling to obtain densities in forest and non-forest habitats. Most (22/28) restricted-range species were recorded in forest and non-forest. Of 28 restricted-range species, 13 species showed a clear preference for forest and 8 for non-forest, and total numbers were one-and-a-half times higher as high in forest compared with non-forest. Of the 10 most common species, one was more abundant in non-forest and seven were more abundant in forest. We conclude that forest is the primary habitat for the majority of the restricted-range avifauna, and their dependence on forest makes them particularly vulnerable to deforestation. Adequate protection of the forests in these mountains is therefore the best assurance of the long-term survival of these birds.

The Puerto Rican Nightjar Caprimulgus noctitherus is a ‘Critically Endangered’ caprimulgid endemic to coastal dry and lower montane forests of southwest Puerto Rico. I studied nest habitat use of this nightjar at the Guánica Biosphere Reserve in southwestern Puerto Rico. Nightjar nests (n = 23) were located in evergreen and deciduous forest and were more common at elevations above 100 m. Nests were located from 2 m to 125 m into the forest from the nearest road or trail and were characterised by a deep layer of leaf litter, and an open midstorey beneath a closed canopy. Six of the 10 nests found in evergreen forest were located within abandoned mahogany (Sweetenia mahogany) plantations. Habitat structure and vegetation composition were quantified at each nightjar nest and an equivalent number of randomly selected sites. Four of 13 habitat variables differed significantly (P < 0.05) between nest and random sites and included: elevation, leaf litter biomass, midstorey stem density, and canopy closure. Stepwise logistic regression generated a best model describing nightjar nest habitat. Leaf litter biomass, midstorey stem density, and canopy closure correctly classified 77.3% of nightjar nests. Management of forest stands at higher elevations to promote nightjar nest habitat structure, protection of private lands in the periphery of the Guánica Biosphere Reserve, and acquisition of privately owned forest tracts in other portions of the nightjar's range will ensure the long-term persistence of the species.

Colin Bibby (1948–2004) was the quintessential bird conservation biologist. Over his career, he served as lead scientist at two of the world's largest bird conservation organizations, the Royal Society for the Protection of Birds, and BirdLife International. His contributions encompassed detailed autecological studies of rare bird species such as the Dartford Warbler Sylvia undata (e.g. Bibby 1978) and Fuerteventura Stonechat Saxicola dacotiae (e.g. Bibby and Hill 1987), a sweeping synthesis of the techniques of bird conservation science (Bibby et al. 1992, 2000), and pioneering contributions in conservation planning such as the Endemic Bird Areas concept (ICBP 1992).

Belding's Yellowthroat (Geothlypis beldingi) inhabits freshwater marshes the length of the state of Baja California Sur. A gap in occurrence from approximately 25°50′N to 24°50′N separates the subspecies goldmani to the north from beldingi to the south. According to BirdLife International's (2000, 2007) population estimates, the most important sites for the species are San Ignacio (537–648 birds) and La Purísima (203–450) in the north and San José del Cabo (219–480) and Punta San Pedro (70) in the south. Half of 12 presumed breeding sites in the north and five of 14 in the south were discovered within the last ten years. The species apparently no longer occurs at one historical site in the south. Since 2000, two records from Guerrero Negro and one from Bahía Tortugas approximately 140 km and > 200 km respectively northwest of the known breeding range demonstrate the species' dispersal ability. Belding's Yellowthroat is of utmost conservation concern, but the most recent conservation summaries exaggerated the species' plight, in particular by under-appreciating the bird's capacity for long-range dispersal and the ability of marsh habitat to regenerate quickly. Formal studies of the species should be undertaken and marsh creation should be incorporated in the state's development plans. Previous calls for reintroduction efforts should not be heeded, at least for the time being.

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.

A complete census was taken of all colonies of Southern Giant Petrels Macronectes giganteus within the Falkland Islands in 2004/05. The breeding population of the islands was estimated to be approximately 19,529 pairs (range 18,420–20,377). Southern Giant Petrels were found to breed in 38 locations around the islands, with colony size varying from one to 10,936. The majority of colonies were concentrated around the south of Falkland Sound, and to the west of West Falkland. Whilst there has been no previous census of the total population of the islands, there is a strong indication that the population has increased since the 1950s. The reasons for such an increase in population remain unclear in light of current knowledge. Development of our understanding of the breeding biology and demography of this species in the Falkland Islands is necessary, as is the need to conduct such a census every five years, with a few key colonies to be monitored every season. From the results obtained here, the conservation status of the Southern Giant Petrel, currently listed as ‘Vulnerable’, could be downgraded to ‘Near Threatened’.

We describe the breeding phenology and nesting habitat characteristics of San Andres Vireo Vireo caribaeus for the breeding season of 2004. Nest monitoring of colour marked individuals took place in three major vegetation types (dry scrubland, mangrove forest and dense forest) on San Andrés Island, Colombia. In all of them, vegetation structure variables were measured and compared using principal components analysis. A courting song was recorded and its sonograms are presented here. Nineteen nests were monitored between January and June, of which 80% were found in dry scrubland, 10% in mangrove forest and 10% in dense forest. Nesting stages were found to be similar in length to those known for other vireos. Nest construction took 6 ± 0.87 days (mean ± SD), clutch size was 2 ± 1 eggs (mean ± SD), incubation took 17 ± 2.47 days (mean ± SD), and nestling period was 9 ± 1.57 days (mean ± SD). Fourteen nestlings fledged from successful nests (53%) and post fledging care was sustained for 28 ± 4.17 days (mean ± SD). Vireo nests were found in sheltered dry areas, characterized by a thick cover of dead leaves on the ground (≤ 60%) and a low canopy height (mean = 5 m) but providing 60% cover over the nest. Nest trees were healthy plants and 75% of the nests hung from east-facing forked branches at a height of 0.73–2.0 m. Nesting trees were typically surrounded by 3-5 species of fleshy fruit plants fed to chicks. Conservation of the vireo would benefit from maintenance of traditional land use practices in dry scrubland on the island and protection or special management of some areas of this habitat should be considered.

Common Guillemots Uria aalge and Brünnich's Guillemots U. lomvia are common victims of oil spills, drowning in fishing nets and winter wrecks. Because the Norwegian population of Common Guillemots is classified as critically endangered and the Russian population of the Brünnich's Guillemot has declined greatly, it is important to be able to identify the origins of birds killed outside the breeding season. Measurements of birds made in nine colonies in the Barents and Norwegian Seas showed that although it is impossible to determine with reasonable accuracy the colony of origin from body measurements, the most likely sea of origin of Common Guillemots may be determined on the basis of wing and head + bill lengths, whereas there was no systematic variation in any measurement of Brünnich's Guillemots.

Mortality of albatrosses (and petrels) as bycatch in longline fisheries is one of the most important and pervasive sources of mortality for many species and is often closely linked to observed population declines. In the area of the Southern Ocean managed by the Commission for the Conservation of Antarctic Marine Living Resources (CCAMLR), which includes the waters around South Georgia, Prince Edward Islands, Iles Crozet and Kerguelen (the most important sub-Antarctic breeding sites for many albatross - and petrel - species), such bycatch was reduced to negligible levels (in demographic terms) over the last decade. The process by which this was achieved, in terms of data, policy and practice, together with an assessment of the main drivers and obstacles, is described. The extent to which the CCAMLR example is a model for other Regional Fisheries Management Organisations (RFMOs) (and even for states with jurisdiction in relevant coastal waters) is assessed. Some current actions and priorities for further action in relation to seabird bycatch are summarised.

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.

Tropical forests are becoming increasingly degraded and fragmented by logging, which can affect the survival of forest bird species in different ways. In this study, we present avifauna data collected from a monitoring programme in west-central Sumatra that set camera traps in three study areas with different habitat types, levels of degradation and protection status. From 5,990 camera trap-nights, 248 independent bird photographs were recorded, comprising four orders and nine species, including three endemic species. The Great Argus Pheasant (Argusianus argus) was recorded in all study areas and most frequently (n=202 photographs), followed by the threatened Salvadori's Pheasant (Lophura inornata). The greatest diversity of bird species (five) and abundance index (1.44 bird photographs/100 trap-nights) was recorded from a primary hill-submontane forest site located inside Kerinci Seblat National Park (KSNP) bordering degraded forest in a former logging concession recently repatriated into KSNP. However, inside a primary-selectively logged hill-submontane forest site spread over KSNP and an ex-logging concession, a Sumatran Ground Cuckoo (Carpococcyx viridis) was photographed. This species is noteworthy because prior to this study it had only been documented once since 1916. It is therefore crucial to use the camera trap results to increase the protection status for the ground cuckoo area. This has already happened in the other two study areas, where camera trap data have been used to reclassify the areas as Core Zones, the highest level of protection inside KSNP. This study illustrates how routine monitoring can have wider benefits through recording, and conserving, threatened and endemic non-target species in unexpected habitats that might not otherwise have been surveyed.

Since their description in the first half of the 20th century by M. A. Carriker, Bolivian Recurvebill Simoxenops striatus and Yungas Antwren Myrmotherula grisea have been regarded as extremely poorly known endemics of the Bolivian Yungas and adjacent humid foothill forests. They are considered ‘Vulnerable’ under the IUCN criteria of small population, predicted population decline (criterion C2a) and, in the case of Bolivian Recurvebill, small extent of occurrence (criteria B1a+b). Here we summarise the information published to date and present extensive new data on the distribution (including the first records for extreme southeast Peru), natural history, population size and conservation status of both species based on field work in the Bolivian Andes over the past 12 years. Both species primarily inhabit the understorey of primary and mid-aged to older regenerating forest and regularly join mixed-species foraging flocks of insectivorous birds. Bolivian Recurvebill has a strong preference for Guadua bamboo, but it is not an obligate bamboo specialist and persists at often much lower densities in forests without Guadua. Yungas Antwren seems to have a preference for dense, structurally complex understorey, often with Chusquea bamboo. Both species are distributed much more continuously at altitudes of mostly 600–1,500 m, occupy a greater variety of forest types (wet, humid, semi-deciduous forest) and have a much greater population size than previously thought. Consequently, none of the IUCN criteria currently used to assign ‘Vulnerable’ status to both species actually apply, and we recommend them to be downlisted to ‘Near Threatened’.

Gyps vulture populations across the Indian subcontinent collapsed in the 1990s and continue to decline. Repeated population surveys showed that the rate of decline was so rapid that elevated mortality of adult birds must be a key demographic mechanism. Post mortem examination showed that the majority of dead vultures had visceral gout, due to kidney damage. The realisation that diclofenac, a non-steroidal anti-inflammatory drug potentially nephrotoxic to birds, had become a widely used veterinary medicine led to the identification of diclofenac poisoning as the cause of the decline. Surveys of diclofenac contamination of domestic ungulate carcasses, combined with vulture population modelling, show that the level of contamination is sufficient for it to be the sole cause of the decline. Testing on vultures of meloxicam, an alternative NSAID for livestock treatment, showed that it did not harm them at concentrations likely to be encountered by wild birds and would be a safe replacement for diclofenac. The manufacture of diclofenac for veterinary use has been banned, but its sale has not. Consequently, it may be some years before diclofenac is removed from the vultures' food supply. In the meantime, captive populations of three vulture species have been established to provide sources of birds for future reintroduction programmes.

The distribution and abundance of Spanish Imperial Eagle Aquila adalberti populations between 1974 and 2004 were determined using information from national censuses. Its breeding area occupies the south-western quadrant of the Iberian Peninsula (Spain and Portugal) and is composed of 13 nuclei and 5 subpopulations. Since 1974, population levels in all nuclei, except the one in Doñana, have expanded. The non-breeding dispersion area, according to sightings of juvenile and immature individuals in quadrants of 10 x 10 km, coincided with that of the breeding area. Bibliographical information showed that halfway through the 19th century the Spanish Imperial Eagle was considered abundant, at least locally; and most cited breeding areas were in relatively human-occupied plains. Towards the end of the 19th century the population became scarce; remaining so for most of the 20th century, with remote mountain ranges being the most cited breeding habitats. The comparison between the data from the first census, in 1974, that located 38 territorial pairs, and the 2004 census that located 198 pairs, shows that: 1) percentages of pairs in plains have increased, while those in mountains have decreased; 2) the trophic quality of the habitat, based on rabbit abundance, has decreased, and 3) numbers of nests in both protected areas and on private ground have increased significantly. The type of land ownership did not seem to affect breeding performance. Populations have increased more outside protected areas than within, despite the availability of potential habitat. In the past century, legal protection and attitude changes towards this eagle seem to have been influential in preventing its extinction. At present, habitat management seems also to be an important factor in its continuing recovery.