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Summary Limestone karst habitats are threatened globally by quarrying for production of concrete and cement. A significant area of limestone karst shared among the provinces of Saraburi, Lopburi and Nakhon Ratchasima in Thailand encompasses the entire global range of a threatened bird taxon, the Rufous Limestone Babbler Gypsophila calcicola. We estimate that 10% of the suitable habitat for this species had already been lost to quarrying by 2020, and the extension of already proposed concessions could increase this to one-quarter, with the total area impacted by proposed future quarrying as great as 273 km2, or one and a half times greater than the entire area thought to support the species, within a few years. Only 2.66 km2 (1.4% of the species’ range) has received formal habitat protection as national park. We propose further surveys of the babbler be incorporated as part of a wider biotic survey of the Saraburi Group Limestones, leading to the development of an integrated management and zoning plan that takes account of the distributional knowledge of other threatened endemic taxa of this region.

SummaryPopulations of the globally endangered Giant Nuthatch Sitta magna have declined significantly throughout their small world range in southern China and northern continental South-East Asia. Distance sampling and direct observations were used to estimate the density and habitat use of the Giant Nuthatch in a potential stronghold for the species, Chiang Dao Wildlife Sanctuary, Thailand. Thirteen line transects covering 6.2 km were established in open, pine-oak habitat favoured by the nuthatch, during November 2014 to December 2015. The mean density of Giant Nuthatch was 3.94±1.22 (95% CI = 2.15–7.22) individuals/km2. Hierarchical distance sampling models indicated that habitat use by Giant Nuthatch was strongly correlated with trees of large diameter. A pair of Giant Nuthatches was radio-tracked as they fed nestlings during the 2016 breeding season. The female’s home range, centred on the nest, was 7.79 ha (95% kernel home range), approximately one-fourth of that of the male, 32.01 ha. Giant Nuthatches showed a significant preference for foraging on pines Pinus spp. and used the fissured bark of mature pines in which to store acorns of deciduous tree species. Our research indicates the importance of large, mature trees in open pine-oak forest in supporting Giant Nuthatch populations.

SummaryThe Giant NuthatchSitta magnais a globally endangered species presumed to be declining, for which basic parameters of population and habitat associations remain largely unquantified. We focused on Myanmar, which potentially constitutes ~30% of the Giant Nuthatch global range and yet lacks recently published records. Our objectives were to survey key potential Giant Nuthatch localities in, or near, historical locations in Southern Shan State, assess its population status, and quantify habitat associations. Preliminary locality surveys focused on four potential forest patches, assessed by walking approximately 40 km of trails. The species was found in only one of the four localities (Mt. Ashae Myin Anauk Myin [AMAM]), an 18 km2forest patch in Pindaya and Lawksawk Townships. Here, point counts and vegetation surveys were conducted at 46 locations using an adaptive cluster sampling design. N-mixture models were applied to estimate abundance and identify habitat variables correlated with abundance and detection probability. We also conducted a brief quantitative assessment of tree use and foraging behaviour during one breeding season. Our population estimate for AMAM was 56 individuals (95% CI 25–128) based on a sampled area of 3.25 km2. Abundance was positively associated with larger diameter trees, a higher proportion of pine and oak combined based on their total basal area, and negatively correlated with elevation. Foraging data suggested that Giant Nuthatch preferred to feed on trunks and large branches of larger diameter pines and Fagaceae trees. Based on the estimated population size, AMAM is probably a globally significant locality for Giant Nuthatch and the only confirmed locality in Myanmar since 1992 but is threatened by agricultural expansion. More detailed understanding of the habitat requirements of this endangered species and an assessment of its distribution at the landscape-level, especially in Shan State, would increase the precision of global population estimates.

Understanding the movements and requirements of individual species within bird migration flyways is of crucial conservation importance, especially along the East Asian Flyway considering the immense human pressure on the environment and habitats. We attached satellite transmitters to females of four Chinese Sparrowhawks Accipiter soloensis and four Japanese Sparrowhawks A. gularis mist-netted on their southward passage through Thailand. The Chinese Sparrowhawks wintered across a c. 3000 km-wide longitudinal span from Sumatra to Timor-Leste, spending 84–173 days on their wintering grounds before returning to breeding grounds in south and east China. Two were tracked for complete migration cycles of 14,688 and 9694 km, respectively. Three of four Japanese Sparrowhawks were tracked to wintering grounds in Sabah, Kalimantan, and the Bangka Belitung Islands where they spent 168–173 days before returning north. The Bangka Belitung winterer was tracked to presumed breeding grounds in Amurskiy Oblast, eastern Russia, traveling 7757 km in 53 days. Daily flights varied widely up to c. 800 and 382 km for Chinese and Japanese Sparrowhawk, respectively. With few individuals sampled, no significant differences were found within or between species, in the daily distances flown during southward or northward journeys. However, Japanese Sparrowhawks made fewer stopovers suggesting they traveled faster on northward migration than Chinese Sparrowhawks. Movements during the wintering and nesting periods were mostly confined to areas of less than 23 km2, although one wintering Chinese Sparrowhawk used an area of over 600 km2. Further work is needed to improve knowledge of the annual cycles of these and other migratory East Asian raptors and how they might differ among age- and sex-classes within species.

We re‐evaluated the taxonomy of the Striated Prinia Prinia crinigera–Brown Prinia P. polychroa complex using molecular, morphological and vocal analyses. The extensive seasonal, sexual, age‐related, geographical and taxon‐specific variation in this complex has never before been adequately studied. As no previous genetic or vocal analyses have focused on this group, misinterpretation of taxonomic signals from limited conventional morphological study alone was likely. Using mitochondrial and nuclear DNA, we found that P. crinigera sensu lato (s.l.) comprises two non‐sister groups of taxa (Himalayan crinigera and Chinese striata groups) that differ substantially morphologically and vocally and that are broadly sympatric in Yunnan Province, China. Prinia polychroa cooki (Myanmar) and P. p. rocki (southern Vietnam) are each morphologically, vocally and genetically distinct. Thai, Cambodian and Laotian populations formerly ascribed to P. p. cooki are morphologically and vocally most similar to and most closely related to Javan P. p. polychroa, and require a new name, proposed here. Prinia p. bangsi of Yunnan is part of the crinigera group rather than of P. polychroa, and hence there is no evidence for sympatry between P. polychroa s.l. and P. crinigera s.l., nor of the occurrence of P. polychroa in mainland China or Taiwan. We recommend the recognition of five species in the complex, with the following suggestions for new English names: Himalayan Prinia P. crinigera sensu stricto (s.s.; with subspecies striatula, crinigera, yunnanensis and bangsi); Chinese Prinia P. striata (subspecies catharia, parumstriata and striata); Burmese Prinia P. cooki (monotypic); Annam Prinia P. rocki (monotypic) and Deignan's Prinia P. polychroa s.s. (subspecies Javan polychroa and the new Southeast Asian taxon). This study underlines the importance of using multiple datasets for the elucidation of diversity of cryptic bird species and their evolutionary history and biogeography.

We present non-breeding season records of the recently named Alpine Leaf Warbler Phylloscopus occisinensis from Bangladesh (four individuals) and northern Thailand (one). Identification was based on mitochondrial DNA assay of feathers or blood from birds handled during ringing. Tickell's Leaf Warbler P. affinis (sensu lato) was abundant in scrub and scattered trees at the margins of wetlands in north-east Bangladesh, whilst the record from Thailand represents a significant eastwards extension of the previously recorded wintering range. Further sampling in South and South-East Asia will be necessary to resolve the winter ranges of the taxa affinis and occisinensis.

With nearly 400 migratory landbird species, the East Asian Flyway is the most diverse of the world’s flyways. This diversity is a consequence of the varied ecological niches provided by biomes ranging from broadleaf forests to arctic tundra and accentuated by complex biogeographic processes. The distribution and migration ecology of East Asian landbirds is still inadequately known, but a recent explosion in the number of studies tracking the migration of raptors, cuckoos, kingfishers and passerines has greatly increased our knowledge about the stopover and wintering ecology of many species, and the migratory routes that link northeast Eurasia and the Asian tropics. Yet the East Asian Flyway also supports the highest number of threatened species among flyways. Strong declines have been detected in buntings (Emberizidae) and other long-distance migrants. While the conservation of migratory landbirds in this region has largely focused on unsustainable hunting, there are other threats, such as habitat loss and increased agro-chemical use driven directly by land cover change and climate-related processes. Important knowledge gaps to be addressed include (1) threats affecting species in different parts of their annual cycle, (2) range-wide population trends, (3) ecological requirements and habitat use during the non-breeding season, and (4) the conservation status of critical wintering sites (including understudied farming landscapes, such as rice fields) and migration bottlenecks along the flyway.

Morphological traits have served generations of biologists as a taxonomic indicator, and have been the main basis for defining and classifying species diversity for centuries. A quantitative integration of behavioural characters, such as vocalizations, in studies on biotic differentiation has arisen more recently, and the relative importance of these different traits in the diversification process remains poorly understood. To provide a framework within which to interpret the evolutionary interplay between morphological and behavioural traits, we generated a draft genome of a cryptic Southeast Asian songbird, the limestone wren-babbler Napothera crispifrons. We resequenced whole genomes of multiple individuals of all three traditional subspecies and of a distinct leucistic population. We demonstrate strong genomic and mitochondrial divergence among all three taxa, pointing to the existence of three species-level lineages. Despite its great phenotypic distinctness, the leucistic population was characterized by shallow genomic differentiation from its neighbour, with only a few localized regions emerging as highly diverged. Quantitative bioacoustic analysis across multiple traits revealed deep differences especially between the two taxa characterized by limited plumage differentiation. Our study demonstrates that differentiation in these furtive songbirds has resulted in a complex mosaic of colour-based and bioacoustic differences among populations. Extreme colour differences can be anchored in few genomic loci and may therefore arise and subside rapidly.

Many birds wintering in the Indian subcontinent fly across the Himalayas during migration, including Bar-headed Geese (Anser indicus), Demoiselle Cranes (Anthropoides virgo) and Ruddy Shelducks (Tadorna ferruginea). However, little is known about whether shorebirds migrate across the Himalayas from wintering grounds beyond the Indian subcontinent. Using geolocators and satellite tracking devices, we demonstrate for the first time that Common Redshanks (Tringa totanus) and Whimbrels (Numenius phaeopus) wintering in Singapore can directly fly over the Himalayas to reach breeding grounds in the Qinghai-Tibet Plateau and north-central Russia respectively. The results also show that migratory shorebirds wintering in Southeast Asia can use both the Central Asian Flyway and the East Asian-Australasian Flyway. For Redshanks, westerly-breeding birds crossed the Himalayas while more easterly breeders on the Plateau migrated east of the Himalayas. For Whimbrels, an individual that crossed the Himalayas was probably from a breeding population that was different from the others that migrated along the coast up the East Asian-Australasian Flyway. The minimum required altitude of routes of trans-Himalayan Redshanks were no higher on average than those of eastern migrants, but geolocator temperature data indicate that birds departing Singapore flew at high elevations even when not required to by topography, suggesting that the Himalayan mountain range may be less of a barrier than assumed.

— It is often assumed that passerine birds conceal nests to reduce predation because nest predation is usually the primary cause of reproductive failure. We hypothesized that nesting success would be higher in nest cavities with more concealed entrances and therefore more likely chosen over less concealed cavities. We set 200 nest boxes in ∼100 territories of White-rumped Shamas (Copsychus malabaricus), territorial cavity nesters, in a seasonal evergreen forest in northeastern Thailand. Shamas were provided two boxes per territory, one with high and the other with low vegetation cover in front of the box entrance. Boxes were reset in new locations after a nest fledged or failed, providing 170 ‘choice' trials. We also compared vegetation characteristics of natural nest cavities with available natural nest cavities. Contrary to predictions, shamas placed nest material in the less concealed boxes significantly more often (89 boxes vs. 48), were significantly more likely to lay eggs in less concealed...

Background Roost-site quality can significantly affect the individual fitness of shorebirds, but roost sites remain poorly described for many threatened species on the East Asian–Australasian Flyway. We studied roost-site selection of the globally endangered Spotted Greenshank (Tringa guttifer) in the Inner Gulf of Thailand, an area which supports approximately 24% of their global wintering population, during two non-breeding seasons (October 2014–May 2015 and December 2015–February 2016). Methods We measured nine variables associated with roost site characteristics including water depth, indicators of disturbance/predation risk, and associations with other shorebird species. We predicted that roost ponds with shallow water in proximity to foraging sites would receive higher usage than those further away. Results A total of 94 sites were measured of which 46 were used for roosts with 23 used repeatedly. All used sites were human-modified ponds, of which 44 were used for salt farming and two used for aquaculture. Roosts were on average 1.10 ± 0.78 (SE) km from foraging sites and 5.8 ± 2.4 cm deep. The most supported model indicated that roost sites were negatively associated with distance to foraging sites and positively associated with the presence of Grey Plover (Pluvialis squatarola) and water depth. Conclusions Traditional saltpans and other artificial wetlands near (

The Spotted Greenshank (Tringa guttifer) is one of the most threated shorebird species in the world, but key environmental characteristics associated with its presence are still not well understood. Here we summarised historical records and recent survey results of wintering Spotted Greenshanks in Thailand, a country of particular importance for overwintering populations of the species, and constructed a species distribution model to examine four environmental variables associated with occupied sites in Thailand, including coastal type (rocky, sandy, muddy or mixed sandy beach), distance to estuary, distance to mangrove forest, and tide range, to identify suitable habitat for wintering Spotted Greenshanks. The results indicated that distance to estuary and coastal type had the largest effects suggesting that Spotted Greenshanks preferred muddy or mixed sandy coast and estuarine habitats. A few new potential areas were predicted along the coasts of Chantaburi-Trat, in the extreme eastern Thai Gulf, and Ranong and Phang Nga Provinces, on the Andaman Coast of Southern Thailand, which have not been previously surveyed for Spotted Greenshank. We suggest that rapid establishment of comprehensive surveys, especially boat surveys, in the predicted areas could help to discover previously unknown sites for wintering Spotted Greenshanks and assist our understanding of patterns of their habitat selection.

The Japanese sparrowhawk Accipiter gularis is a small raptor that breeds in Northeast Asia. The species consists of the widespread and mostly migratory subspecies A. g. gularis that is common in East Asia, including Japan, and the resident and endangered subspecies A. g. iwasakii which inhabits the Ryukyu and Yaeyama Islands in Okinawa, southern Japan. Given the minimal knowledge about the migration of the species, in this study we sought to compare the genetic variation of the populations breeding in Japan with those migrating through Southeast Asia. We sequenced 761 bp of mitochondrial DNA Control Region from each of 21 A. gularis collected during the breeding season in Japan and from 20 individuals intercepted on migration in Thailand. We detected 26 haplotypes among the 41 individuals which differed significantly between Japan and Thailand. Migrants in Thailand were presumed to have originated from a wide area in Eastern Eurasia. The phylogenetic and network analyses demonstrated that the haplotypes of all A. g. gularis detected in Japan were genetically close. Moreover, the Okinawa haplotypes of A. g. iwasakii were clustered with moderate genetic variation. The information presented here can be used towards implementing future conservation actions.

Seasonal variation in food supply may not adequately explain avian breeding phenology in tropical areas with relatively stable climates. In northeastern Thailand the Red-headed Trogon (Harpactes erythrocephalus) and Orange-breasted Trogon (H. oreskios) share similar nest sites, diets, foraging habitats, and foraging techniques but differ in timing of reproduction even though their food supply of insects varies in a similar seasonal pattern, peaking in June for both species. For the Red-headed Trogon, egg laying lasts 5–6 months and peaks in May; nestling provisioning coincides with peak food availability. For the Orange-breasted Trogon, by contrast, egg laying lasts 2–3 months and peaks in February. This nesting period is shorter and earlier than that of most other species of birds at our study site, and nestling provisioning preceded the period of peak food by 4 months. Timing of breeding by the Orange-breasted Trogon may represent a compromise between breeding at the optimal time based on food...

Adult Long-toed Stints Calidris subminuta, spending the non-breeding season at a coastal fresh to brackish water site in central Thailand, commenced moult of primaries soon after their arrival from their breeding grounds. The estimated duration of primary moult was 70 days, with starting and completion dates 14 August (standard deviation ± 13.3 days) and 23 October. Juvenile/first-year birds did not moult any flight feathers during the 1 July to 31 December study period. The adaptive significance of this rapid moult of flight feathers is probably linked to the influence of monsoon upon food abundance. Birds underwent a rapid moult of flight feathers towards the end of the southwest monsoon (wet season), when food was most abundant, and completed their moult before the onset of the dry season caused many wetland habitats to dry up.

The Brown Hawk Owl complex is said to consist of three species, the Brown Boobook (Ninox scutulata), the Chocolate Boobook (Ninox randi) and the Northern Boobook (Ninox japonica), which includes the nominate migratory lineage Ninox japonica japonica and a mitochondrially distinct lineage of taxonomically uncertain status that has been recorded year-round at least in Taiwan. Overlap in ranges during migration and morphological similarity have led to difficulties in distinguishing the Brown Boobook from the Northern Boobook. PCR of cytochrome-b and Sanger sequencing of Ninox samples from Singapore and Brunei were used to determine sample identity. Two out of four Singaporean samples and the Brunei sample were identified as Northern Boobooks. This is the first official record of this species in Singapore and represents a considerable range extension for the species. Further, the samples belong to the mitochondrially distinct lineage previously characterized in resident Taiwanese populations rather than to the well-known nominate migratory lineage. Our data show that the mitochondrial signature previously documented in resident Taiwanese populations of the Northern Boobook extends to migratory populations. This cryptic lineage may be more widespread in its breeding quarters, extending to the Chinese and Russian mainland, in which case the name florensis would apply to it. Further genetic and bioacoustic investigation is required to resolve the taxonomic status of this lineage.

The Giant Nuthatch Sitta magna is restricted to southwestern China, eastern Myanmar, and northern Thailand. Although globally endangered, most aspects of its ecology remain as yet unquantified. To ...

Distance sampling is usually preferred over uncorrected point counts for surveys of forest birds, but rarely has its accuracy been assessed against known numbers, particularly in tropical forests. We compared density estimates of eight species of breeding bird—Black-naped Monarch (Hypothymis azurea), Hill Blue Flycatcher (Cyornis banyumas), White-rumped Shama (Copsychus malabaricus), Puff-throated Bulbul (Alophoixus pallidus), Abbott's Babbler (Malacocincla abbotti), Puff-throated Babbler (Pellorneum ruficeps), White-browed Scimitar Babbler (Pomatorhinus schisticeps), and White-bellied Yuhina (Yuhina zantholeuca)—obtained through color-banding, nest finding, and territory mapping with those derived from distance methods in evergreen forest in northeastern Thailand. We also assessed the availability of birds to be detected using a closed-capture model and incorporated this with point-transect distance sampling. Abundance estimates from territory mapping and distance sampling were highly correlate...

The Asian Golden Weaver (Ploceus hypoxanthus) occurs in Myanmar, Thailand, Laos, Vietnam, Cambodia, and Indonesia and inhabits marshes, grasslands, reeds and rice fields close to water in the lowlands (Robson 2000) and natural waterholes in lowland dry dipterocarp forest (Round 1998). It is globally ‘Near-threatened’ due to habitat loss through the conversion of wetlands to agricultural and settlement areas (BirdLife International 2007). In Thailand it is local and uncommon in the north, north-east and central regions (Lekagul and Round 1991, Robson 2000). However, no quantitative data are available regarding its ecological requirements. Our objectives were to collect basic ecological data on: i) population structure, ii) nesting habitat characteristics, iii) food selection and foraging behaviour, and iv) parental care at the nest.

Long-term bird population changes in response to natural or anthropogenic factors have been relatively well documented in the temperate zone, but rarely in the tropics, where there are few long-term data sets. Here, we analyze a 25-yr sequence of records of two species of Lophura pheasants, Siamese Fireback L. diardi and Silver Pheasant L. nycthemera in Khao Yai, Thailand's oldest national park. These data suggest that the number and proportion of detections of the lowlands-inhabiting L. diardi have increased significantly in relation to those of the higher elevation inhabitant L. nycthemera. Environmental factors mediated by changing climate are the most plausible explanation for the changing proportions of sightings of the two species. Further work is needed to explore in detail microhabitat selection of these birds and whether changes in microsite conditions on the forest floor or other factors are driving the observed distribution. Long-term monitoring of the avifauna along an elevational gradient is also recommended in tandem with increased monitoring of local climatic conditions.

We present compelling evidence of the continued existence of the large-billed reed warbler Acrocephalus orinus, hitherto known only from the unique type specimen collected in NW India 139 years ago. Morphological and genetic analyses of an unusual Acrocephalus warbler mist-netted south-west of Bangkok, Thailand, on 27 March 2006, confirmed its identity as A. orinus, and revealed that it was heterozygous at four out of eight microsatellite markers, indicating the continued existence of a viable population whose breeding and wintering areas are still unknown.

The numbers and pattern of distribution of dark-bellied brent geese Branta b. bernicla feeding inland around Chichester and Pagham Harbours, West Sussex in winter 1979/80 are described. A maximum of 11,000 birds fed inland. Taking the winter as a whole, 70% fed within 200 m of the coast. 68% of inland-feeding birds occurred on grass. This was partly influenced by deliberate scaring of the geese from cereals. 14% of the available area of grass around Chichester was used by geese but only 6% was heavily grazed. Of the area of cereals, 13% was used with 4% heavily grazed. Unless disturbed, the brent geese usually remained inland for most of the day, regardless of the state of the tide, returning to roost overnight on intertidal areas. The more uniformly distributed food supply in fields enabled the geese to feed in larger, more compact flocks than they could do on the estuary. The provision of grassland refuges is suggested as a means of alleviating conflict with agriculture. For Chichester Harbour up to five refuge areas may be required where the geese can feed undisturbed. Each refuge should not only provide the food requirements of the geese but be large enough to provide a buffer against human disturbance on surrounding land. The total refuge area should probably be not less than about 400 ha, on which many of the normal farming practices can continue. Refuges should be situated adjacent to the coast and the grass sward needs to be closely grazed by livestock or mown in the summer to provide a suitable short sward for the wintering geese.