Wreathed Hornbill Research Articles

Changes in endangered hornbill populations over space and time and potential ecological impacts in peninsular Thailand

Hornbills are particularly important seed dispersers in tropical Asian forests, but most of the species in the region are declining. In addition, long-term data on the extent of the declines and how forest degradation impacts hornbills remain mostly unquantified. Here, we used multi-covariate distance sampling to estimate the densities of hornbills in 2021–2022 in Hala-Bala Wildlife Sanctuary and Budo Su-Ngai Padi National Park protected areas in southern Thailand. These two sites are particularly useful for comparison due to differences in protection levels, with Bala being relatively less disturbed than Budo Mountain and because Bala was surveyed 20 years prior (2001–2002). Fig tree watches were also conducted in 2021–2022 to assess the potential impact of forest disturbance on hornbill visitation rates. Results indicated significant differences in hornbill densities between the two sites. The mean density of the Rhinoceros (Buceros rhinoceros) and Wreathed Hornbill (Rhyticeros undulatus) was 3.2 and 5.1 times higher in Bala than in Budo, while the mean density of the Great Hornbill (Buceros bicornis) was 2.2 times higher in Budo than in Bala. The density of the Helmeted Hornbill (Rhinoplax vigil) was notably lower than other hornbill species. There were also significant changes over the past 20 years in large hornbill densities, with Great Hornbill and Wreathed Hornbill significantly increasing, while the Helmeted Hornbill declined more than 90 %. Also, the probability of hornbills visiting fruiting Ficus trees was higher in the less-disturbed Bala than the Budo Mountain, making hornbills more reliable visitors in the less-disturbed site. We demonstrate the applicability of the multi-covariate distance sampling approach to estimate densities of rare hornbills, the negative impacts of habitat degradation on hornbills and the ecological role they play as seed dispersers. Additional surveys are needed throughout tropical Asia to establish further sites for long-term monitoring, especially in the Sunda region, where the Helmeted Hornbill is under extreme threat.

Hornbill abundance and habitat relationships in a human-impacted protected area in the Indian Eastern Himalaya

Asian forest hornbills play an important functional role as seed dispersers. Three of the large-bodied hornbill species in the Eastern Himalaya are declining globally. To understand their global population status, it is important to obtain reliable abundance estimates across their range. Protected areas are the strongholds for hornbill species in the Eastern Himalaya but differ in degree of disturbances and human pressures. We estimated the abundances of four hornbill species (Great Hornbill, Wreathed Hornbill, Rufous-necked Hornbill, and Oriental Pied-Hornbill) in the human-impacted Buxa Tiger Reserve in northern West Bengal. This is the first study in Asia to obtain abundance estimates of the hornbill species through comprehensive spatial coverage of the reserve. The densities of the three large-bodied species were low (< 1 bird per km2), while that of the small-bodied Oriental Pied hornbill was around 11 birds per km2. Abundance estimates ranged from a mean of 27 birds for the Rufous-necked Hornbill that is confined to the hilly areas to 161 for the Great Hornbill, 375 for the Wreathed Hornbill and 8050 for the Oriental Pied-Hornbill. Habitat quality was poor in most of the reserve with low tree density and basal area with only a few patches with higher tree density. Oriental Pied-Hornbills were associated with lower elevations and higher fruiting tree density. Despite the relatively low abundance of the large-bodied hornbill species, Buxa is an important site for hornbill conservation due to the presence of breeding populations and nests. While past and ongoing human pressures have resulted in habitat degradation, poaching pressures are low and hornbills are able to persist and breed in this landscape. Ecologically meaningful forest restoration with diverse native tree species is urgently needed to improve the habitat quality for hornbills and other wildlife.

A preliminary global investigation into potential impacts on successful captive breeding for two species of Rhyticeros hornbill.

Asian hornbills have limited ex situ breeding success, yet these species are some of the most threatened of birds, in need of managed breeding programs. To optimize breeding and increase the sustainability of such populations, it is necessary to assess and improve their husbandry and welfare. Evidence to improve reproduction can be gathered through global husbandry surveys. A survey was sent out to all European Association of Zoos and Aquaria and Association of Zoos and Aquarium holders of the wreathed hornbill (Rhyticeros undulatus) and Papuan hornbill (R. plicatus) to determine predictors for ex situ breeding success. This research found that pairs that have spent more years together (p = .016) and that adding additional proteins to the diet (p = .006) are two significant predictors of breeding success for wreathed- and Papuan hornbill pairs. This paper found a general trend that successful hornbill pairs prefer nest boxes that are situated outside (p = .054). The behaviors of calling to each other and sitting in close proximity showed a general trend and were observed more frequently in successful pairs and, therefore, could be good indicators of bonded pairs. We recommend that ex situ institutions allow their hornbill pairs time to form strong bonds, and that pair compatibility is monitored regularly to ensure that such interactions are positive and not consistently negative. An increase in the percentage of dietary proteins, priorand during the breeding season appears to stimulate pairs to breed. If the management and husbandry alterations presented in this study are implemented, the sustainability of Rhyticeros hornbill populations may be enhanced.

The Diversity of Avifauna and Potency for Development of Ecoturism in Minangkabau Village, Padang Panjang City

Padang Panjang has several tourist attractions surrounded by secondary forests with natural vegetation, one of them is the Minangkabau Village. The Minangkabau village has potencies to be an ecotourism object. This study aims to analyze the potential of avifauna that have an attraction for ecotourism development, determine the role of stakeholders in supporting ecotourism development in Padang Panjang, and analyze development priorities as its potencies and objects of ecotourism attraction in Padang Panjang. We used The MacKinnon method by conducting direct surveys in the field when the birds are active in the morning and evening. Deep interviews were conducted with Dinas Pemuda Olahraga dan Pariwisata (Disporapar) Kota Padang Panjang to determine stakeholders' role in tourism activities in Padang Panjang. SWOT analysis is carried out to see the priority of ecotourism development so that it is more focused and able to contribute to ecotourism areas and the community. The data obtained were analyzed to calculate the Diversity Index, Species Richness, and Species Evenness. The research results show that the Minangkabau Village areas have high diversity, richness, and evenness of bird species, namely H' 3.21, DM 7.50, and ED 0.85. There were 43 bird species from 23 families. Species that has high conservation status are Serindit Melayu (Loriculus galgulus) protected species, Jalak Kerbau (Acridotheres javanicus) with Vulnerable IUCN status, Julang Emas (Rhyticeros undulatus) Vulnerable IUCN status also protected and 2 species of Eagle (Ictinaetus malayensis and Spilornis cheela). These species have potencies to be developed as an ecotourism attraction object that stakeholders support as coaches and companions. The strategy for developing ecotourism in Padang Panjang under its potencies for biodiversity is to increase public knowledge about animal conservation (especially avifauna), biodiversity, and the adverse effects of hunting and collaborate to manage ecotourism by hiking/jungle tracking and birdwatching.

Gardeners of the forest: hornbills govern the spatial distribution of large seeds

Seed dispersal by frugivores is vital to the maintenance of tree diversity in tropical forests. However, determining the influence of different frugivores over the distribution of their food plants is difficult, given the complexity of these interactions in the tropics. Consequently, most studies have been restricted to small scales, examining seed dispersal and establishment associated with nests, roosts or fruiting trees. Here, we evaluate the role of frugivorous hornbills in dispersing seeds at spatial scales of 1 ha. We monitored hornbills and seed rain at a tropical forest site in north‐east India. We quantified the abundance of hornbill food plants and recruits of large‐seeded plants. We estimated removal rates of dispersed, large seeds to determine post‐dispersal seed fate. We found that the distribution of large‐seeded canopy food plants influenced the distribution of the relatively abundant Rhyticeros undulatus. The overall distribution of hornbills resulted in spatially contagious seed rain patterns for the large‐seeded plant species. Patches with canopy food plants had a higher recruit diversity. Our results show positive feedback between distribution of rare but important hornbill food plants, hornbills and distribution of seeds and saplings of large‐seeded plants in the landscape. Widespread loss of hornbills due to hunting and habitat loss in the region have likely disrupted these feedback mechanisms that are critical for tree species regeneration.

KEANEKARAGAMAN JENIS BURUNG RANGKONG (Bucerotidae) DI STASIUN PENELITIAN WAY CANGUK TAMAN NASIONAL BUKIT BARISAN SELATAN

The rise of hornbill hunting and deforestation that occurred in Indonesia, especially the island of Sumatra lately, threatening the preservation of these birds in nature. The purpose of this study was to determine thediversity of hornbill species in the Way Canguk Research Station, Bukit Barisan Selatan National Park. The method used in this study is a transect line with a total of 18 line transects. The data obtained was processed using the Shanon wienners diversity index formula, then translated with descriptive analysis. A total of 5 types of hornbills found in these locations are rhinoceros hornbills (Buceros rhinoceros), helmeted hornbills (Rhinoplax vigil), wreathed hornbill (Rhyticeros undulatus), bushy crested hornbill (Anorrhinus galeritus) and white crowned hornbill (Berenicornis comatus), with a species diversity index value of 1.00 included in the low category and the evenness of the species is a stable with an evenness index value of 0.62. The highest abundance of hornbills is (Anorrhinus galeritus) a beside that hornbills can be found in almost all transect lines.

Spesies Burung Famili Bucerotidae Pada Ekosistem Tahura Pocut Meurah Intan Sebagai Materi Pendukung Matakuliah Ekologi

Pocut Meurah Intan Forest Park is a natural conservation area and a place of learning, however this condition has changed in line with the high activity of local residents such as illegal logging, forest conversion, wildlife hunting and forest burning. This study aims to determine the types of birds of the Bucerotidae family in the Pocut Meurah Intan Forest Park Ecosystem as a support material for Ecology courses. The method used in this study is the explorative survey method. As the result, this study found 4 (four) bird species from the family Bucerotidae, namely Buceros rhinoceros, Buceros bicornis, Anthrococeros albirostris and Aceros undulatus. The results of this study will be utilized and developed theoretically in Ecology courses in the form of reference books.

How far do Asian forest hornbills disperse seeds?

Biotic seed dispersal of plants is a complex phenomenon that is influenced by multiple seed disperser species with implications for plant fitness and range expansions. While inter-species variation has been well-studied, the importance of incorporating intraspecific variation in seed dispersal is increasingly being acknowledged. We compared seed dispersal patterns of breeding and non-breeding great hornbills Buceros bicornis and a breeding wreathed hornbill Rhyticeros undulatus by combining data on fruiting tree visitations, gut passage time and movement data from tagged hornbills. Seed dispersal probability at nest trees (by breeding males) was low (<12%) suggesting that males scatter-disperse seeds, unlike breeding females that deposit seeds below nest trees. Median seed dispersal distance of great hornbills was 294 m and 254 m in the breeding and non-breeding season respectively, and, the distribution tail was shorter for breeding birds (2.5 km) than non-breeding birds (13 km). The median and maximum seed dispersal distance by the wreathed hornbill was 1.35 km and 11 km respectively. This study highlights intraspecific variation in seed dispersal patterns across sexes and breeding and non-breeding male hornbills and potential variation between two hornbill species. This is the first study that estimates long-distance seed dispersal by Asian hornbills.

VARIASI INTERSPESIFIK JULANG (AVES: BUCEROTIDAE) INDONESIA BERDASARKAN GEN CYTOCHROME-B DNA MITOKONDRIA

Genetic information of Indonesian hornbills (Julang) is still limited. We sequenced the cytochrome b gene of three hornbill species (Rhyticeros undulatus, R. plicatus, and Aceros cassidix) to explore their genetic variation, distance, and phylogenetic. Nine blood samples for Cyt b from three hornbill species were isolated with Dneasy® Blood and Tissue Kit base on Spin-Column Protocol, Qiagen. SNP, genetic distance, and phylogeny were calculated by MEGA 6.0 software. This study was found variations in the Cyt b gene sequence (849 bp) between three species Indonesian Julang. Rhyticeros undulatus had the most SNP compared to R. plicatus and Aceros cassidix. Substitution of synonyms is more common than substitution of synonyms and transition substitution frequency tends to be much higher than transversion substitution. The three species of Indonesian Julang were markedly separate with an average genetic distance of 5.25%. and separated with the outgroup species at a genetic distance of 9.43%. Cytochrome b sequence genes from these three hornbill species are novel for identifying and classifying hornbills, and could be applied to prevent illegal poaching and conservation management in Indonesia.

Comparative analysis of the gut microbiota of hornbill and toucan in captivity.

Gut microbiota plays an important role in animals and are considered microbial organs. Hornbill and toucan are birds of the same ecotypes with high appreciative value. In this study, we characterized and compared the gut microbiota of toco toucan (Ramphastos toco), great hornbill (Buceros bicornis) and wreathed hornbill (Rhyticeros undulatus) using 16S rRNA high‐throughput sequencing technology, and further discussed the influence of host bird genetics on its gut microbiota. We identified 10,847 operational taxonomic units (OTUs) from the hyper‐variable V4–V5 region, representing 14 phyla that were dominated by the Firmicutes, Proteobacteria, Cyanobacteria, Fusobacteria, Actinobacteria, and Bacteroidetes. Alpha diversity indices showed no significant difference among the three species (p > 0.1). However, great hornbill and toco toucan shared a high number of OTUs. Principal component analysis also revealed highly similar gut microbiotas between the two distant species. Therefore, environmental factors might dominate over host genetics in shaping the gut microbiotas of hornbill and toucan. Our study would contribute in elucidating adaptation of the hornbill and toucan to environmental change.

Wreathed Hornbill (Rhyticeros undulatus) in Mount Ungaran Central Java: Status and Factors that Threaten Its Existence

Mount Ungaran in Central Java is one of the Important Birds Areas (IBA) in Indonesia where one of the Hornbill species, Wreathed Hornbill (Rhyticeros undulatus) is found. Based on the IUCN 2016, Wreathed Hornbill has been listed as Least Concern (LC) and listed in Appendix II of the CITES. In order to conduct preservation and in-situ conservation planning of Wreathed Hornbill scientific data on ecology is needed. Therefore, the research on the Wreathed Hornbill in Mount Ungaran has been planned since 2010‒2016. The results include species identification, early population and distribution, daily behaviour, habitat profile, nest-site characteristics, feeding behaviour, food consumed, habitat suitability and threats. While study on the dynamics of the home range of Wreathed Hornbill in Mount Ungaran is still ongoing. The implementation of this research is jointly pursued with the Forest Department, Natural Resources Conservation Center (BKSDA), Perhutani Central Java, Indonesia Hornbill, and LIPI (Indonesian Institute of Sciences), and IBBS (Indonesian Bird Banding Scheme).

Cavity Management Enhanced the Allelic Distribution of Great Hornbills in Eastern Khao Yai National Park

Khao Yai National Park, covering an area of 2,168 km2, is very rich in wildlife. The park includes mainly monsoon evergreen forests inhabited by four species of hornbills, namely Anthracoceros albirostris, Buceros bicornis, Ptilolaemus austeni and Rhyticeros undulatus. Among these species, Great Hornbills, B. bicornis, are the largest birds and require the most in terms of quantity and quality of natural resources. They require very large cavity which is in short supply in the wild. The western part of the park supports a high population of Great Hornbills while in the eastern part has low density. From 2009, the study has been expanded to cover the eastern part. Following seven consecutive years (2009‒2015) of nest management, we studied the uses of nests with 4 microsatellites DNA markers specific for each allele of Great Hornbills. This study is to examine non-invasively the 49 DNA samples from mainly tailed feathers. We collected DNA from the shed feathers at or near the nests from Eastern and Western Khao Yai. The population structure analysis revealed by microsatellites markers, showed the inbreeding coefficient (Fis) of the local hornbills of Western Khao Yai improved from 0.45 in 2009 to -0.028 in 2015 with great genetic diversity. In 2014, these hornbills introduced 6 of 9 alleles into the Eastern Khao Yai (locus Bbi 3). Data showed the population connectivity between the two subpopulations. The gene flows potentially increase between the west and the east. Nonetheless, heterozygosity of Great Hornbills in the Eastern Khao Yai significantly improved from HObs = 0.615 to 0.750. Results also showed the availability of suitable nest cavities attracted hornbills from the western to eastern Khao Yai. This molecular approach indicates that the nest cavity management is one of the important strategies to secure the longterm survival of hornbills.

Sumatran Hornbills in Fragmented Forest Areas in Oil Pam Plantation in South Solok, West Sumatra

A study on hornbill populations in fragmented forest areas within oil palm plantations in Tidar Kerinci Agung (TKA) Company, West Sumatra was carried out from July to August 2015 in 60 Hectare fragmented forest areas. The objective of this study was to document hornbill species richness using the transect method on three main lines along two km and using call recognition for population census of hornbill. During the study, we recorded 82 individuals of eight species after 60 km walk. We encountered using two methods (Sighting and Calls Methods); Anorrhinus galeritus twenty-one encounters, Berenicornis comatus single encounter, Rhabdotorrhinus corrugatus two encounters, Rhyticeros undulatus two encounters, Anthracoceros malayanus sixteen encounters, Anthracoceros albirostris seven encounters, Buceros rhinoceros thirty-one encounters and two encounters of Rhinoplax vigil.

Community Structure of Hornbills in an Oil Palm Landscape in East Kalimantan, Indonesia

Conserved land in human dominated landscapes such as oil palm plantations provide habitat for many animal taxa including hornbills. The aim of the study is to quantify species richness, distribution, population size and sex ratio of hornbill community in oil palm landscapes with retained native forest patches. Ecological sampling was conducted in an oil palm plantation in East Kalimantan, Indonesia. Birds were observed using fixed radius point count method. We found that there were six hornbill species belonging to four genera of Bucerotidae including Helmeted Hornbill, Rhinoceros Hornbill, Wreathed Hornbill, Wrinkled Hornbill, Black Hornbill and Oriental Pied Hornbill that occurred in the study site. Population density varied among species ranging from 0.17 to 4.72 individual per km2 in 2012 and 0.34 to 3.35 individual per km2 in 2013. Rhinoceros Hornbill was the most abundant species observed in one location with highest number of individual per group of about 21 individuals during flocking. Sex ratio (M:F) was ranged from 0.31 to 0.95. The dispersion of hornbill species was generally random. Our results show that retention of forest patches on oil palm plantations can help to maintain the diversity and abundance of hornbills in the region.

Characterization and phylogenetic analysis of the complete mitochondrial genome sequence of Rhyticeros undulatus (Bucerotiformes: Bucerotidae)

The wreathed hornbill (Rhyticeros undulatus) has been listed in the IUCN Red List of Threatened Species, because of decreasing population trend. There is a lack of genomic information on this species, which can provide valuable resource for conservation biology and phylogenetic studies on hornbill birds. Here we first characterized the complete mitochondrial genome (mitogenome) sequence of R. undulatus by next-generation sequencing and conducted phylogenomic analysis of hornbill species with mitogenome sequences available. The complete mitogenome of R. undulatus was 17,842 bp in length and incorporated 13 protein-coding genes (PCGs), 2 ribosomal RNA (rRNA) genes, 22 transfer RNA genes, and 1 control region (D-loop). The overall nucleotide composition of this mitogenome was 30.3% A, 22.4% T, 32.6% C, and 14.7% G, with AT content of 52.7%. Phylogenomic analysis using mitogenomes of eight hornbill birds showed that R. undulatus was more closely related to Penelopides panini and two Aceros species.

Short Communication: The nest characteristics of Wreathed Hornbill (Rhyticeros undulatus) in Mount Ungaran, Central Java, Indonesia

Rahayuningsih M, Kartijono NE, Retnoningsih A. 2017. Short Communication: The nest characteristics of Wreathed Hornbill (Rhyticeros undulatus) in Mount Ungaran, Central Java, Indonesia. Biodiversitas 18: 1130-1134. Java has three species of hornbills, one of them is the Wreathed Hornbill (Rhyticeros undulates Shaw, 1811) that can be found mainly throughout on Mount Ungaran, Central Java, Indonesia. The main threats to Wreathed Hornbill population are habitat fragmentation and forest clearing. The large trees used for nesting by the Wreathed Hornbill are usually located in areas of illegal logging. Therefore, it is necessary to study the characteristics of Wreathed Hornbill nests, especially in Mount Ungaran. Eight nests were discovered, six of which were active. The nests were found at 900-1200 m above sea level. Trees that were used as nest sites were between 24-35 m high, and had a diameter of 0.83-1.75 m. Nests were located at heights of 1-27 m, and had a hole diameter of 33-38 cm, hole length of 170-211 cm, entrance width of 4-11 cm, entrance length of 14-39 cm, nest thickness 6-18 cm, and a temperature of 20-21°C. The nest shapes were oval, ellipse, and irregular oval. Commonly, the Wreathed Hornbills used Syzygium glabratum, Syzygium antisepticum, and Cratoxylum formosum for nesting.

Nest Records of Wreathed Hornbill (Rhyticeros undulates) in Gunung Gentong Station, Mount Ungaran Central Java

The remaining forest of Mount Ungaran, Central Javais the suitable habitat of Wreathed Hornbill (Rhyticeros undulatus), especially for a nesting site. The objective of the study was to analyse the nest record and characteristics of habitat around the nest, especially in Gunung Gentong station. The research was conducted from 2010-2016 using exploration method. The methodhabitat profile of the vertical structure tree canopy was taken by plot size 60 × 20 m. Measurements were taken to the standing of vegetation, canopy closure, the direction of the canopy, height canopy, a former branch of the vegetation height, and stem diameter. The Result of the study showed that Gunung Gentong is one of the research station that we have been recorded for nesting site on 2010-2015. Atotal of the nest record on Gunung Genting station was 10 nests. Estimate the elevation of nest location between 939-1240 AMSL. The tree species that used for nesting was Syzygium glabatrum, Syzygium antisepticum, Ceratoxylon formosum, and Ficus sp

Fruit resource tracking by hornbill species at multiple scales in a tropical forest in India

Abstract:The fruit-tracking hypothesis predicts a positive association between frugivores and fruit abundance over space and time. We documented hornbill diets and examined the relationship between fruit abundance and abundance of three hornbill species (Buceros bicornis, Rhyticeros undulatus and Aceros nipalensis) in the Eastern Himalaya from 2009–2012. The study was carried out at three scales: at the largest scale of the study area (15 km2), at the intermediate scale – eight 3-ha patches within the study area and at the smallest scale of individual fruiting trees. Ninety-one per cent of the 64 foraging sightings of the great hornbill were on figs while more than 50% of the foraging sightings of the wreathed (83) and rufous-necked hornbills (87) were on non-fig fruits. At the largest scale, wreathed hornbill abundance and ripe fruit abundance peaked in the non-breeding season. At the intermediate scale, wreathed hornbill abundance was positively associated with non-fig fruit availability while rufous-necked hornbill abundance was negatively associated with non-fig fruit availability. At the smallest scale, great and rufous-necked hornbill abundances were correlated with fig and non-fig fruit crop sizes, respectively. The three hornbill species track fruit availability at different scales based on diet, which has implications for their role in seed dispersal.

Looking beyond parks: the conservation value of unprotected areas for hornbills in Arunachal Pradesh, Eastern Himalaya

AbstractThe loss of tropical forests and associated biodiversity is a global concern. Conservation efforts in tropical countries such as India have mostly focused on state-administered protected areas despite the existence of vast tracts of forest outside these areas. We studied hornbills (Bucerotidae), an ecologically important vertebrate group and a flagship for tropical forest conservation, to assess the importance of forests outside protected areas in Arunachal Pradesh, north-east India. We conducted a state-wide survey to record encounters with hornbills in seven protected areas, six state-managed reserved forests and six community-managed unclassed forests. We estimated the density of hornbills in one protected area, four reserved forests and two unclassed forests in eastern Arunachal Pradesh. The state-wide survey showed that the mean rate of encounter of rufous-necked hornbills Aceros nipalensis was four times higher in protected areas than in reserved forests and 22 times higher in protected areas than in unclassed forests. The mean rate of encounter of wreathed hornbills Rhyticeros undulatus was twice as high in protected areas as in reserved forests and eight times higher in protected areas than in unclassed forests. The densities of rufous-necked hornbill were higher inside protected areas, whereas the densities of great hornbill Buceros bicornis and wreathed hornbill were similar inside and outside protected areas. Key informant surveys revealed possible extirpation of some hornbill species at sites in two protected areas and three unclassed forests. These results highlight a paradoxical situation where individual populations of hornbills are being lost even in some legally protected habitat, whereas they continue to persist over most of the landscape. Better protection within protected areas and creative community-based conservation efforts elsewhere are necessary to maintain hornbill populations in this biodiversity-rich region.

Rapid assessment of Wreathed Hornbill Aceros undulatus (Aves: Bucerotidae) populations and conservation issues in fragmented lowland tropical forests of Arunachal Pradesh, India

A rapid assessment of Wreathed Hornbills, their distribution and abundance was carried out in fragmented lowland tropical forests of Lower Dibang Valley District, Arunachal Pradesh, northeastern India from October 2010 to April 2011 using the total count method. A total of 62km distance was covered on foot to survey four study sites: Horupahar, Delo, Koronu and Injunu. Nine flocks of 172 hornbills were sighted. Aceros undulatus flock size ranged from 8-38 individuals with a mean of about 19.1 plus or minus 2.6. Illegal logging, hunting for bushmeat and other body parts (feathers, beak etc.) for decorating the head gear and house interiors by the local tribals were observed as the major threats to the species in the study areas.