The conservation status of the Blue-backed Parrot Tanygnathus everetti, a species endemic to the Philippines, has long been obscured by its former taxonomic status as a subspecies of the Azure-rumped Parrot T. sumatranus of Sulawesi, Indonesia. A detailed review of evidence from museum material and birdwatchers' records indicates it is known from Luzon, Polillo Islands, Panay, Negros, Samar, Leyte, Mindanao and the Sulu archipelago. There is no evidence it survives on Luzon, Polillo Islands, Panay, Negros and Leyte. On Samar its numbers have dwindled towards extinction but it is likely to survive in tiny numbers (total <100) in the illegally logged Samar Island Natural Park (SINP). On Mindanao it has virtually disappeared from the only known predictable site, the PICOP logging concession at Bislig, and the few records elsewhere suggest <100 persist on the island. In the Sulu archipelago, it may survive in tiny numbers (<50) on Jolo (Bud Dajo National Park) and Tawi-Tawi in the Malum watershed. Records are mainly from primary lowland forest below 450 m, and it appears much less adapted to more open forest formations than its relative, the Blue-naped Parrot T. lucionensis. The almost total clearance of lowland forest in the Philippines, especially primary formations, is assumed to have greatly constrained its distribution and numbers. However, this has been compounded by a barely documented but evidently relentless trade in wild-caught birds. Legal protection for the last vestiges of forests holding this species is called for. SINP needs immediate protection from rampant logging and any poaching. An intensive survey of anticipated and known key sites is urgent, along with a broadscale community campaign to discourage the catching and keeping of parrots, plus an active search for captive birds to form an ex situ conservation breeding initiative. Any such initiative should keep the population on the Sulu archipelago (subspecies burbidgii) separate from T. everetti found in the rest of the Philippine islands, as they are so different.
The Sulawesi Subregion was traditionally thought to be home to a single, resident Phylloscopus leaf warbler. However, recent exploration has revealed an additional three species, two of which have only very recently been described: Taliabu Leaf Warbler Phylloscopus emilsalimi and Peleng Leaf Warbler P. suaramerdu from the outlying islands of Taliabu and Peleng, respectively. The third, 'Selayar Leaf Warbler', remains undescribed, but here we provide the first bioacoustical documentation of its unique song, along with recommending that Sulawesi Leaf Warbler P. sarasinorum sensu lato should be regarded as two species: Lompobattang Leaf Warbler P. sarasinorum and Sulawesi Leaf Warbler P. nesophilus, based on distinct bioacoustics and morphology.
A Chinese Leaf Warbler Phylloscopus yunnanensis was sound-recorded on Baekryeong Island, Incheon, South Korea, on 1 and 2 May 2020. This is the first adequately-documented national record of the species. The calls and song of this species are diagnostic, and identification in the field based on these vocalisations was straightforward and immediate. However, there is a strong prevalence in East Asia to place much higher value on records confirmed by photographs, specimens or in-the-hand measurements than on records documented only with sound-recordings. We therefore analysed the recordings to confirm the bird's identity. While the origins of a preference for visual documentation are understandable, a wider acceptance of the value of sound-recordings in documenting the presence or absence of species will likely prove immensely helpful in improving the understanding of the distribution, abundance and conservation status of many taxa which are morphologically extremely similar.
The Masked Finfoot Heliopais personatus is among Asia's most threatened waterbirds. The species formerly ranged widely across north-east India, Bangladesh and South-East Asia, but recent records are few. In this review, we aim to address the gaps in knowledge on the conservation status and ecology of the Masked Finfoot by (1) synthesizing recent information on its occurrence in all range states, (2) re-estimating the global population based on best guesses of national populations, and (3) identifying priority conservation actions. Based on a combination of our survey data (Bangladesh) and best-guess estimates from key sites, we estimate the current population at 108-304 individuals, far lower than the last estimate of 600-1,700 individuals in 2009. Our estimate of population size and rate of decline indicates that Masked Finfoot should be uplisted to Critically Endangered. Masked Finfoot may now breed only in Bangladesh and Cambodia, and there have been no records within the past five years in Malaysia and Thailand, where it once occurred regularly, despite a marked increase in observer effort. Habitat loss and disturbance is the single most important threat to the Masked Finfoot (and many riverine waterbird species), given that low-lying, forested wetlands across South-East Asia are increasingly encroached upon by human activities, or are cleared. There is an urgent need to re-survey areas where it was formerly known, especially in Myanmar. All remaining known breeding populations must be adequately protected or it may become Asia's next avian extinction.
The Ayeyarwady River, Myanmar, is exceptionally important for waterbirds and other riverine species. Results from mid-winter boat-based surveys in 2017-2019 demonstrated the high conservation value of the river's avifauna. We recorded a total of 83 waterbird species and 18 species listed as Globally Threatened (7) or Near Threatened (11) under IUCN criteria, 16 of which were waterbirds. Counts of many waterbird species were in numbers high enough for the designation of seven river sections as Wetlands of International Importance under the Ramsar Convention on Wetlands. The middle reaches of the Ayeyarwady River between Myitkyina and Bagan hosted more than 40,000 waterbirds in 2019, qualifying this stretch for Ramsar designation under Criterion 5. However, these numbers were already considerably reduced compared to those regularly observed in similar surveys between 2000 and 2007. Species present in this earlier period, such as Masked Finfoot Heliopais personatus, Spot-billed Pelican Pelecanus philippensis and Black-necked Stork Ephippiorhynchus asiaticus, were not recorded during the more recent surveys, and appear to have declined or disappeared. The waterbird species with the highest counts were Ruddy Shelduck Tadorna ferruginea, Cattle Egret Bubulcus ibis and Little Pratincole Glareola lactea, but counts of the shelduck and the pratincole have declined in recent years. Some nesting species, such as the Globally Threatened Black-bellied Tern Sterna acuticauda and River Tern S. aurantia, appear to be on the brink of extinction on this river, and Indian Skimmer Rynchops albicollis may have already been lost as a breeder. The river is subject to a wide range of increasing pressures from a growing human population, including agriculture, gold mining, sand and pebble abstraction and poaching, and high levels of disturbance associated with these activities, contributing to apparent declines of several species. Recommendations for urgent conservation action include the designation of Ramsar sites, and establishment of community-based conservation areas.
The extensive coastline of Sumatra, Indonesia, is known to support internationally significant congregations of migratory waterbirds along the East Asian-Australasian Flyway (EAAF), including multiple globally threatened species such as Nordmann's Greenshank Tringa guttifer and Great Knot Calidris tenuirostris. Yet, many gaps remain in our knowledge about key shorebird sites on Sumatra's coastline and the precise conservation status of shorebird species, with Aceh in northern Sumatra being among the most poorly surveyed regions. From October 2019-January 2020, we undertook large-scale exploratory surveys covering the entire eastern (Malacca Straits) coast of Aceh (c.450 km) to determine the occurrence of congregations of migratory shorebirds at potential areas of coastal wetlands identified a priori, and to identify priority sites for future conservation action. Our surveys revealed large, previously unknown, congregations of shorebirds, with over 10,000 individuals across 34 species detected. Of these, three species, Lesser Sand Plover Charadrius mongolus, Long-toed Stint Ca. subminuta and Broad-billed Sandpiper Ca. falcinellus, exceeded the 1% threshold of their EAAF population estimates. We also found important populations of several globally threatened waterbirds (e.g. Milky Stork Mycteria cinerea) and near threatened species (various shorebirds). Our study provides a new baseline for shorebird monitoring in Aceh province, and we call for stronger conservation action to protect coastal wetlands, particularly the natural and artificial wetlands in Kuala Parek and Ulee Matang.
Hunting of wildlife for subsistence and both local and domestic trade is widespread across Laos. Market surveys with a focus on wild birds were conducted from February 2015 to February 2016. A total of 1,020 individual birds were detected in the trade in local markets. 718 individuals were identified to 13 orders, 30 families and 84 species, while 302 individuals could not be identified to the species-level. Black-crested Bulbul Pycnonotus melanicterus (183 individuals), Red Junglefowl Gallus gallus (85 individuals) and Eastern Spotted Dove Spilopelia chinensis (81 individuals) were found to be the most abundant species sold in markets. The highest species richness and abundances were found at Ban Kok and Ban Chout Song markets. Species richness and abundance of birds traded were highest during the dry season. The most expensive and the cheapest species per individual were Common Hill Myna Gracula religiosa (US$61.30) and Black-headed Bulbul Pycnonotus atriceps (US$0.25-1.23) respectively. Observations of bird populations in surrounding areas are needed to relate their population trends with hunting effort for further conservation actions.
Habitat use and requirements of waterbird assemblages are often spatiotemporally variable. Conservation management needs to be planned to consider seasonally- occurring waterbird communities. The Yunnan-Guizhou Plateau is an important wintering region for waterbirds in China. It is unclear how wetlands on the plateau are consistently utilised as habitat by waterbirds across different seasons. We conducted three surveys per month over two years from March 2013 to February 2015 at Lake Dianchi, the largest lake on the Yunnan-Guizhou Plateau, to determine multi-year waterbird species composition, annual similarity in species composition, and migratory consistency of species to better inform waterbird conservation. We detected approximately 60,000 individuals of 93 waterbird species at Dianchi. Annual species richness exhibited three peaks representing spring, autumn and winter migratory seasons. Year-on-year similarity in species composition was high for different groups, especially residents and summer visitors. The annual variation in waterbirds abundance exhibited a single peak in winter because of the high abundance of Anatidae and Laridae. Charadriiformes, such as shorebirds and plovers, had relatively low numbers of individuals, but exhibited high (R = 0.95, P < 0.01) to modest (R = 0.57, P < 0.01) migration consistency during the northward (spring) and southward (autumn) migrations. We highlight the importance of Dianchi for waterbird conservation. We suggest that waterbird conservation activities such as monitoring schemes should consider seasonal variation, especially for waders during the migratory seasons.
Although camera-trapping is one of the most non-invasive and efficient survey tools for studying wildlife distribution and ecology, it does not seem to be widely established as a survey tool for bird species. We examined the practicality of using camera traps in detecting scansorial birds in central Japan. We chose 221 camera-trapping sites on two mountains in central Japan, during two spring-autumn periods. The sensor cameras were placed at 2-3 m above the ground and facing tree trunks. We recorded all six possible species of scansorial birds with the exception of one species which is a winter visitor. Four of these species were endangered and/or semi-endangered species in the regions. Our results suggest that tree trunk camera-trapping has potential for detecting scansorial birds and providing new information on the ecology of such species.
Eight species of hornbill occur in the Lower Kinabatangan Wildlife Sanctuary, Sabah. Hornbills are secondary cavity-nesting birds and one of the limiting factors to sustain their numbers is the availability of naturally-formed tree cavities. Past timber extraction has left behind highly degraded forest patches without large emergent trees that usually provide suitable cavities for nesting hornbill pairs. Therefore, we conducted a study to assess how widespread this key resource is and to estimate the proportion of a forest patch currently occupied by potential nest trees, i.e. trees with cavities. In a 10 km(2) study site, eight trained observers systematically visited 30 250 m x 250 m plots and recorded tree cavities that appeared suitable for hornbills based on a pre-established list of criteria. Nineteen trees with cavities were located, measured and identified. We anticipated that cavities could go undetected by the observers; we therefore used a zero-inflated process occupancy model to address this measurement error and to analyse data obtained along transects. The observers detected trees with cavities in 10 out of 30 plots, translating into an observed proportion of roughly 33%. However, our model indicated that trees with cavities might actually occupy 25 out of 30 plots, i.e. 82% of the forest patch area. Our modelling approach incorporates imperfect detection through hierarchical modelling and constitutes a quick and cost-effective assessment tool that can be used to investigate the spatial presence of potential nest trees, an important resource for hornbills.
We conducted annual surveys on wintering waterbirds at a total of 81 wetland sites on China's Hainan Island from 2008 to 2020. These surveys recorded 82 waterbird species. Little Egret Egretta garzetta, Lesser Sand Plover Charadrius mongolus and Kentish Plover C. alexandrinus were the most abundant species, while Little Egret, Chinese Pond Heron Ardeola bacchus and Common Sandpiper Actitis hypoleucos were the most widespread. We discovered a new and important wintering site for the endangered Black-faced Spoonbill Platalea minor in Danzhou Bay. Our data also suggest that Hainan may be a regular wintering site for a small number of Great Knot Calidris tenuirostris and Nordmann's Greenshank Tringa guttifer. Sites of particular importance included Dongzhaigang, Houshui Bay, Danzhou Bay, Beili Bay, Changhuajiang River Estuary and Yinggehai Saltpans, but not all of them are formally protected at present. Our longitudinal data suggest an increasing trend in the total number of waterbirds counted, but this most likely reflects increased survey effort over the years, improving field skills of surveyors and a growing knowledge of important waterbird sites. The average annual count of waterbirds recorded during our 13-year survey period was relatively low compared with some nearby wetlands of importance on the mainland. Our surveys also detected continuous declines of waterbirds at some sites. To safeguard the future of Hainan's waterbirds and their habitats, we recommend establishing new or expanding existing protected areas at key sites, and enhancing management and enforcement efforts throughout the island.
The Rufous-fronted Laughingthrush Garrulax rufifrons shares the western part of the island of Java, Indonesia, with close to 100 million people. Historically it has been recorded from 15 mountains but post-2000 records all come from two of them (Gn Gede-Pangrango and Gn Slamet). Illegal trade for the cage-bird market is considered to be the main threat to the species; it is currently listed as Critically Endangered. Despite trade being the main threat, well-documented records of birds for sale and associated price data are scarce. Based on 174 surveys of 11 Javan bird markets (August 2016 to February 2020), we here report on the trade (volume, price developments and temporal patterns) in Rufous-fronted Laughingthrush. The species was recorded in 21% of the surveys, with a total of 61 birds (all adult-sized); in addition, we found seven birds offered for sale on online platforms. Prices were relatively low at similar to US$69 and these prices differed geographically. We found no temporal changes in numbers or prices. We assessed that birds were sold on average within two weeks after arriving at the bird market and based on this we estimate that overall some 90 Rufous-fronted Laughingthrushes are sold in these markets annually. Our surveys raise the possibility that the species persists on other mountains in western Java and underscores the value of bird market surveys in gaining insight into how trade affects the conservation of imperilled bird species.
The Bangladesh Sundarbans (6,017 km(2)) is part of the largest single block of halophytic mangrove forest in the world, and parts of it are listed as a Ramsar and UNESCO World Heritage Site. The Sundarbans supports globally important populations of threatened species such as the White-rumped Vulture Gyps bengalensis, Masked Finfoot Heliopais personatus, Brown-winged Kingfisher Pelargopsis amauroptera and Mangrove Pitta megarhyncha. Despite its global significance, little information is available on its avifauna. Published checklists and accounts on the relative abundance of birds have been fragmentary or only covered a small part of the forest. Most ornithological studies carried out in the Sundarbans were on specific species or groups (e.g. waterbirds). Considering the global importance of this vast mangrove forest and our gaps in ornithological knowledge, the status and relative abundance of birds in the Bangladesh Sundarbans were assessed based on 33 visits by the author between 2005 and 2019, covering major habitat types. To generate a comprehensive, evidence-based and updated checklist of the birds of the Bangladesh Sundarbans, in addition to the author's own observations, published and unpublished materials were extensively reviewed. A total of 299 species are documented from the Bangladesh Sundarbans, comprising 160 resident and 139 migratory species. Current or historical status and distributions of three Critically Endangered, four Endangered, three Vulnerable and 19 Near Threatened species are discussed in detail. In addition, threats to the avian communities, key knowledge gaps and the need for long-term monitoring are also presented.
Unsustainable wildlife trade across South-East Asia has contributed significantly to the extinction threats faced by many songbirds. The Barusan Shama Copsychus (malabaricus) melanurus, a highly-prized songster from the West Sumatran Archipelago, is one of the most threatened taxa in Asia's songbird trade crisis, yet its predicament is often overlooked because some taxonomists treat it as a mere subspecies of the widespread White-rumped Shama C. malabaricus. Here, we provide the first modern comprehensive assessment of the on-the-ground status of Barusan Shamas across all major islands of the West Sumatran Archipelago based on visual and bioacoustic surveys, mist-netting activity, as well as community interviews covering approximately the last five years. A lack of ornithological field records across many years as well as documented drops in local capture rates indicate that increasing poaching pressure and market value have likely driven the Barusan Shama to extinction in the wild on all islands except Siberut. Even on Siberut, we document a drastic population crash and estimate impending extinction in the wild within perhaps five years in the absence of considerable changes in human behaviour. The decline and presumed extermination of some Barusan Shama island populations was so precipitous that it became evident even within our five-year monitoring period. Although our field efforts and those of others must continue, this bird's future now likely hinges on ex situ conservation efforts. The Barusan Shama occurs in four described subspecies, each endemic to its own island group, further complicating conservation efforts. Although the nominate subspecies melanurus remains relatively common in captivity on Nias and Mentawai, the other three subspecies are currently known from captive populations of a magnitude of about 100 for hypolizus, a handful for opisthochrus and zero for mirabilis, casting doubt on whether ex situ efforts can be initiated fast enough to assure the survival of individual subspecies.
There is controversy about bird mortality at tailings ponds. Tailings ponds are known to directly cause deaths of birds and other animals in three ways, including oiling, poisoning and suffocation or dehydration/exhaustion. Tailings ponds are part of the industrial process and are used to store mine tailings, which are end-of-the-pipe waste sand products of mining operations. However, these ponds sometimes resemble lakes or wetlands. Their similarity to natural lakes attracts birds seeking roosting sites and foraging opportunities. The inability to differentiate between a natural lake and a tailings pond affects bird survival. Here we review reports on incidents, relevant findings and quantitative estimates of bird mortality from oiling and poisoning at tailings ponds across the world, and add a special focus on two White-naped Cranes Antigone vipio that we tracked. Effects of tailings ponds on bird populations, specifically on endangered or declining species and juveniles/subadults, are discussed, with a particular focus on China. Finally, some suggestions are given on the prevention of bird mortality at tailings ponds, such as light and sound deterrence, and a minimum safe distance between tailings ponds and places where birds congregate, such as migration corridors like rivers or lakes.
Aerodramus fuciphagus (Thunberg 1812), with the type locality 'Java', is widely used as the species name of swiftlets that produce the best quality 'white' edible nests. The author of this name, Carl Peter Thunberg, made a short diversion from the route from Buitenzorg (Bogor) to Batavia (Jakarta) in June 1777 to visit caves at Mount Tjerreton. Here he was presented with examples of the swiftlets and the edible nests made by them, as described and illustrated in a subsequent publication. The later nomenclatural vagaries of the Edible-nest Swiftlet of Java were resolved by demonstration that the type of nest built is species-specific, and therefore that Thunberg's name has undoubted validity and priority. In an attempt to find the type locality, a field visit in 2018 compared Thunberg's description of 'Tjerreton' ('Cherreton' in the English translation) with a hill and cave currently known as Keraton. Although the outcome was not conclusive, we are convinced that Thunberg's edible-nest swiftlets were from a cave in the Tajur-Klapanunggal karst area. One cave (Gajah) has been an important source of edible birds' nests from the 17th century to the present time. In the year 1948 the harvest from Gajah cave was 106,671 nests (approximately 1,000 kg). In 2017-2018, single harvests from Gajah cave were just over 2 kg, denoting a huge decline now threatening the topotypical population of this important species.
Loop migration, i.e. the use of different routes during spring and autumn migration, is a common migratory strategy among many long-distance migratory species. This migration strategy is most likely driven by the variation in food availability and/or prevailing winds en route between the spring and autumn seasons. Tracking studies and long-distance ring recoveries have revealed that many of the species that migrate along the American and Eurasian-African migratory flyways use different stopover sites in spring and in autumn. However, very little information is available on songbirds migrating along the East Asian flyway. In this study, we compared the wing lengths of six East Asian long-distance migratory passerines (Red-flanked Bluetail Tarsiger cyanurus, Siberian Rubythroat Calliope calliope, Taiga Flycatcher Ficedula albicilla, Arctic Warbler Phylloscopus borealis, Thick-billed Warbler Arundinax aedon and Black-faced Bunting Emberiza spodocephala) migrating through two different study sites in Russia. We examined whether these species show morphological differences between spring and autumn migration which could indicate the occurrence of different populations at different parts of the migratory cycle. Based on a dataset of 2,368 adult individuals, we found no differences in wing length between the two seasons for four studied species, suggesting the absence of loop migration. This might be explained by adequate food supply and similar prevailing wind directions for birds in both spring and autumn, or the lack of obvious ecological barriers along the East Asian flyway which have to be crossed during migration. However, the differing wing lengths of individuals captured in spring and autumn for two species, Black-faced Bunting and Red-flanked Bluetail, provide evidence for the possible use of different seasonal migratory routes. Further field studies are needed to better understand the migration ecology of passerine birds in the East Asian flyway.
