We conducted a 16-month country-wide survey to determine the status of the threatened Madagascar (Marsh) Harrier Circus macrosceles from 2005 to 2006. We searched for harriers in varying habitat types, focusing on marshes, grasslands and savannas, secondary forests and the edge of primary forests. We surveyed 68% of the districts of Madagascar which contain 71% of the potential harrier habitat throughout the country. We recorded 80 individuals of this sexually dimorphic raptor; 48 males and 32 females of which 71 were observed during the breeding season (June to December) and nine outside the breeding season (January to May). The Madagascar Harrier has a broad distribution of about 1,000 km north to south (Madagascar is about 1,500 km in length) and east to west, but at extremely low density. Fifty-three (69%) harriers were observed in high elevation marshes and grasslands above 1,100 m in the provinces of Mahajanga and Antananarivo during the breeding season. Three major threats to harriers, all human caused, were identified: the transformation of marshes to rice fields (all nests in lower elevation natural marshes), uncontrolled fires destroying nests (n = 7 nests lost in 2005 to fires), and human persecution by taking young from nests for a food source and killing adults due to their predatory nature. From our surveys in Madagascar and information from Comoro Islands, we estimate the global population to be 250–500 individuals suggesting the current Madagascar Harrier population is heading towards endangerment. The survival of the Madagascar Harrier in Madagascar is critically dependent on protecting the remaining natural marshes, which are an extremely limited and critically endangered habitat in Madagascar, with bordering grasslands.

The avifauna of the Mariana Islands, an archipelago in the western Pacific, faces the threats of rapid economic development and the spread of non-native species, particularly a devastating predator, Brown Tree Snake Boiga irregularis. In this paper, we examine the status and trends of the land bird fauna of Saipan Island based on three island-wide surveys conducted in 1982, 1997, and 2007. During this period, the human population on Saipan increased more than four-fold and much of the island has been developed. The surveys employed standard point-transect methods based on Distance Sampling. Remarkably, we found nearly all species of land birds - 11 native species and three introduced species - to be common or abundant. The exception was the Micronesian Megapode Megapodius laperouse, a historically rare species that was not observed on the 2007 survey, although it does persist on Saipan and other Mariana islands. A comparison of species densities among the three surveys showed that seven species, mainly fruit and seed-eaters, had increased and three species of insectivorous birds had decreased - Rufous Fantail Rhipidura rufifrons, Nightingale Reed-warbler Acrocephalus luscinia, and Golden White-eye Cleptornis marchei. Of these three, Nightingale Reed-warbler is listed as ‘Endangered’ on the IUCN Red List and as an Endangered Species by the U.S. Fish and Wildlife Service. Reed-warbler densities on Saipan decreased by more than half between 1982 and 2007. Although point transect sampling worked well for this species, density estimates and trends assessment could be improved by reallocating sampling stations among habitats and by more frequent sampling.

The study area at Zait Bay, Egypt (c. 700 km2) is situated in the middle of the West Asian-East African migration flyway used by very large numbers of soaring migrants. At this site the corridor narrows into a bottleneck. There exist only very few bottlenecks of this magnitude in the world. Observations were performed at all hours between sunrise and sunset at 26 observation sites, situated 5 km apart. The northern part of the area under investigation (19 observation sites) was situated within the Gebel El Zeit IBA (criteria A1 and A4iv), while the southernmost part (8 observation sites) was outside. The overall evaluation has shown that 179,681 soaring birds including 122,454 storks and 36,976 raptors were observed in total. Within a radius of 2.5 km from each observation site 97,143 soaring birds including 59,308 storks and 30,489 raptors were observed during the 604 hours of observation. Eleven species were recorded in numbers that exceed 1% of their flyway populations. Of special concern regarding bird conservation are those birds resting or flying in the first 200 m of elevation. In total 6,624 soaring birds were seen resting (2,252 within a radius of 2.5 km). Thirty-three percent of the storks and 47% of the raptors were observed resting or flying at heights within the lowest 200 m. The median height of flying birds varied between 5 m (harriers) and 500 m (Common Crane Grus grus). According to the raw data, criteria for nomination of the area as an IBA (20,000 raptors and storks in one migration season, globally threatened species) were fully met outside the existing IBA. Also, to the south of the study area, very high numbers of migrants were confirmed by spontaneous, non-systematic observations. Accordingly, a change of the boundaries is suggested. The regional analysis, based on extrapolations, has to be regarded as a preliminary study. The analysis failed to show a geographical trend for any single species. The data from this study establish a high concentration of gliding and soaring birds in the study area, within and adjacent to the already designated IBA.

Gurney's Pitta Pitta gurneyi was not seen in the wild for over 30 years before its rediscovery in a small area in southern Thailand in 1986. In 2003, it was found over a much larger area in southern Myanmar (Burma) after an even longer absence of records. This paper reports the results of recent research on both populations. In Myanmar, birds were found in a high proportion of visited sites, including sites up to 40 km further north than any previous records in the country. Occupied forest sites had a higher density of seedlings, saplings, bamboo and rattan than unoccupied forest sites, suggesting a preference for regenerating forest. There was no evidence of a decline in the species's likelihood of occurrence up to at least the highest visited altitude of 230 m. Maximum entropy models suggested a potential range size of between 3,200 and 5,800 km2 and the predicted range extended just over the border into Thailand, suggesting that birds might persist there. Population estimates for southern Myanmar ranged from 9,300 to 35,000 territories, with a mid-point estimate of 20,000 territories, based upon range sizes modelled from different parameters and a range of territory densities estimated from Thailand. The population in southern Thailand was estimated at between 15 and 20 territories in 2003, 2005 and 2007, and there was a reduction in the historic rate of forest loss in the core range over the same period, suggesting that long-term declines have been at least temporarily contained by recent conservation intervention. However, nesting success in Thailand was very low, due to heavy nest predation by cat snakes Boiga. Nests were usually built close to waterlogged areas and damp gullies, and nestlings were fed almost exclusively on earthworms. Occupied sites in Thailand had a higher density of seedlings, saplings, spiny palms and rattans, but sparser ground cover and a lower density of large trees and bamboo, than forests in Myanmar, indicating their secondary nature. Occupied and unoccupied sites in Myanmar were structurally more similar to each other than either was to occupied sites in Thailand. The results suggest that the species might inhabit a wider range of altitudes, slopes and forest types than previously thought, and so might persist in previously unsurveyed areas and might survive or even benefit from a degree of forest disturbance. However, the species's conservation-dependent status in Thailand and accelerating forest clearance in Myanmar suggest that forest protection measures are urgently needed to secure its long-term future.

Fragmentation of continuous habitat blocks into small, isolated patches may cause gradual replacement of habitat specialists by generalists and edge-dwelling species, thereby altering trophic interactions within communities. When fragmentation progressively increases the edge-to-interior ratio of forest remnants, forest birds are typically exposed to higher levels of nest predation, especially so near forest edges. However, the strength and direction of this ‘edge effect on nest predation’ may vary with predator communities, which in turn can be affected by habitat type, landscape structure and geographical location. We studied avian nest predation in two isolated forest fragments in the Taita Hills of southeast Kenya, where small mammals, rather than birds, dominate predator communities. The use of artificial ground nests allowed us to reduce variation in laying date and microhabitat use, which are known to affect predation on natural nest in the study area. Predation rates did not increase near the forest boundary, but instead, were higher in the forest interior of one of the fragments. Such inverse edge effects may be caused by forest-dependent small mammals or snakes that can remove bird eggs. Although inverse edge effects may be more common in East African tropical forests than previously thought, and should therefore be taken into account when drafting conservation plans, the underlying mechanisms remain unclear. Further study of the population dynamics of small mammals and snakes, and their relative impact on nest predation in fragmented habitats, is therefore required.

We undertook a 3-week expedition to Papua New Guinea in April-May 2007 to assess the breeding, threats and population densities of the Papuan Harrier Circus spilonotus spilothorax and to determine a first global population estimate for this almost entirely unknown species. Two of the first nests known were discovered in April 2007 with three chicks each, in the eastern lowlands, in rank grass and reeds. The melanistic form of this subspecies was more common in the lowlands (< 1,500 m a.s.l) than in the highlands, but interbreeding of this and the typical form occurred in the lowlands. Movements of identifiable individuals through two highland grasslands indicated up to eight birds per day on passage, corroborating local knowledge that other raptors move into the highlands at the start of the dry season (April). Linear road counts indicated no harriers in the wooded highlands but up to 2.9 harriers 10 km−1 in lowland grasslands. Area counts gave an average of 6.5 harriers 100 km−2 in the grasslands and a breeding density of 1.21 nests 100 km−2. Given that preferred grassland and swamp habitat comprises c. 7% of the forest-dominated island of New Guinea, the global Papuan Harrier population can be no more than c. 3,600 birds and c. 740 breeding pairs. Wildfires peaked at 38 per month in the study area, occur throughout the dry season, and led to the loss of both nests. This suggests that many nests and prey may be lost at critical times and burning may be ultimately detrimental for the species. Grassland fires throughout Indonesia and Papua New Guinea are increasing with climatic warming and ENSO events, so we suggest that the Papuan Harrier may warrant a ‘Vulnerable’ conservation ranking due to small total population size and an accelerated reduction in habitat quality due to ongoing climate change.

The Restinga Antwren (Thamnophilidae: Formicivora littoralis) is endemic to a small region on the coast of Rio de Janeiro state in southeastern Brazil. Currently, it is considered ‘Critically Endangered’ by IUCN due to continuing habitat loss within its very small and severely fragmented range. Data available to assess its conservation status, however, are scarce. From 2005 to 2007, we conducted bird surveys to produce more rigorous estimates of geographic range limits, available habitat, local population density, and global population size. We used these data and IUCN criteria to reassess the conservation status of the Restinga Antwren. We recorded the species in a new locality (Tucuns, Armação dos Búzios), expanding its range by 5 km from the easternmost known limit. The species was present in 65% of the points surveyed within its range, in restinga fragments that cover an area of c. 42 km2 (84% of the total restinga within the species’s range). We estimated that this bird has an Extent of Occurrence of 233.5 km2, an Area of Occupancy of 148 km2, and a global population size < 5,000 individuals. We therefore recommend downlisting Restinga Antwren from ‘Critically Endangered’ to ‘Endangered’. We also recommend that the Massambaba and the Pau Brasil Areas of Environmental Protection be transformed into Biological Reserves, to increase restrictions on human activities in the area and preserve crucial habitat for the Restinga Antwren.

Conservationists often find it difficult to assess long-term population change in a species when the only data available are from disparate sources. This is especially the case when a range of survey methodologies and reporting units have been utilised and the results have been published in the ‘grey’ literature. Although the production of a cohesive assessment of change may be a daunting task, in such circumstances, a sound assessment of change is often possible. We illustrate this by considering the decline of the Twite Carduelis flavirostris in England. Whilst there is evidence of decline, it is widely dispersed and the losses have yet to be formally documented. To assess longer-term change, we reviewed information available in county avifaunas and historical accounts of the status of the species throughout its former English range. Twite now only breed regularly in six of their 12 historical range counties, and in all of these six, the birds have declined markedly in abundance. We collated and analysed data drawn from a diverse range of surveys and county bird reports to assess more recent change and assessed contemporary distribution and abundance during our own surveys of breeding colonies in the South Pennines, an area supporting the last known nesting colonies in England. Combined, the data clearly indicate that the range and numbers of breeding Twite have declined considerably since the 1970s. Recent re-surveys in the South Pennines indicate a significant range contraction, with a loss of Twite from 83% of 1-km grid squares found occupied during a 1990 survey. A detailed resurvey of historical breeding sites in east Lancashire revealed a similar pattern, with 77% of sites having lost their colonies over the last four decades. We also constructed an index of change in numbers on the east and south-east coastal wintering grounds used by English breeding birds and this shows that numbers have severely declined since the 1970s, mirroring change on the breeding grounds.