CamTrapAsia: A dataset of tropical forest vertebrate communities from 239 camera trapping studies

Information on tropical Asian vertebrates has traditionally been sparse, particularly when it comes to cryptic species inhabiting the dense forests of the region. Vertebrate populations are declining globally due to land-use change and hunting, the latter frequently referred as "defaunation." This is especially true in tropical Asia where there is extensive land-use change and high human densities. Robust monitoring requires that large volumes of vertebrate population data be made available for use by the scientific and applied communities. Camera traps have emerged as an effective, non-invasive, widespread, and common approach to surveying vertebrates in their natural habitats. However, camera-derived datasets remain scattered across a wide array of sources, including published scientific literature, gray literature, and unpublished works, making it challenging for researchers to harness the full potential of cameras for ecology, conservation, and management. In response, we collated and standardized observations from 239 camera trap studies conducted in tropical Asia. There were 278,260 independent records of 371 distinct species, comprising 232 mammals, 132 birds, and seven reptiles. The total trapping effort accumulated in this data paper consisted of 876,606 trap nights, distributed among Indonesia, Singapore, Malaysia, Bhutan, Thailand, Myanmar, Cambodia, Laos, Vietnam, Nepal, and far eastern India. The relatively standardized deployment methods in the region provide a consistent, reliable, and rich count data set relative to other large-scale pressence-only data sets, such as the Global Biodiversity Information Facility (GBIF) or citizen science repositories (e.g., iNaturalist), and is thus most similar to eBird. To facilitate the use of these data, we also provide mammalian species trait information and 13 environmental covariates calculated at three spatial scales around the camera survey centroids (within 10-, 20-, and 30-km buffers). We will update the dataset to include broader coverage of temperate Asia and add newer surveys and covariates as they become available. This dataset unlocks immense opportunities for single-species ecological or conservation studies as well as applied ecology, community ecology, and macroecology investigations. The data are fully available to the public for utilization and research. Please cite this data paper when utilizing the data.

Using global remote camera data of a solitary species complex to evaluate the drivers of group formation

The social system of animals involves a complex interplay between physiology, natural history, and the environment. Long relied upon discrete categorizations of "social" and "solitary" inhibit our capacity to understand species and their interactions with the world around them. Here, we use a globally distributed camera trapping dataset to test the drivers of aggregating into groups in a species complex (martens and relatives, family Mustelidae, Order Carnivora) assumed to be obligately solitary. We use a simple quantification, the probability of being detected in a group, that was applied across our globally derived camera trap dataset. Using a series of binomial generalized mixed-effects models applied to a dataset of 16,483 independent detections across 17 countries on four continents we test explicit hypotheses about potential drivers of group formation. We observe a wide range of probabilities of being detected in groups within the solitary model system, with the probability of aggregating in groups varying by more than an order of magnitude. We demonstrate that a species' context-dependent proclivity toward aggregating in groups is underpinned by a range of resource-related factors, primarily the distribution of resources, with increasing patchiness of resources facilitating group formation, as well as interactions between environmental conditions (resource constancy/winter severity) and physiology (energy storage capabilities). The wide variation in propensities to aggregate with conspecifics observed here highlights how continued failure to recognize complexities in the social behaviors of apparently solitary species limits our understanding not only of the individual species but also the causes and consequences of group formation.

Environmental factors induced crop raiding by wild Asian elephant (Elephas maximus) in the Eastern Economic Corridor, Thailand

Crop raiding are an increasing concern in wildlife conservation. This study identified the environmental factors that cause wild Asian elephants (Elephas maximus) to enter sub-urban and rural areas and share resources with humans in the Eastern Economic Corridor (EEC) in the eastern part of Thailand. The snowball method was used to interview villagers that had crop raiding experienced in seven provinces of the EEC and adjacent provinces in the eastern part of Thailand in 2020, and data from 183 households indicated that crop raiding had increased continuously from 2000 to 2020, especially in Chonburi, Chachoengsao, and Prachinburi provinces, which have seen increases in damaged agricultural areas. MaxEnt analysis showed an increase in incidents of crop raiding, while the elephants distribution area decreased from 9534 km2 in 2000 to 5199 km2 in 2010 and 4850 km2 in 2020. The study area has had land use changes in the low elevations from croplands of cassava and sugar cane to eucalyptus, para rubber, and fruits. These mixed crop plantations provide a pseudo-habitat for wild Asian elephants. The results from this study provide evidence that changes in land use and reduction of suitable habitat are factors that influenced the movement of wild Asian elephants to the rural agricultural areas and increased the incidents of crop raiding.

Abundance and physical factors affecting the appearance of selected terrestrial birds in Khao Yai National Park using camera trapping

Abstract. Kanka P, Sukmasuang R, Duengkae P, Siripattaranugul K. 2023. Abundance and physical factors affecting the appearance of selected terrestrial birds in Khao Yai National Park using camera trapping. Biodiversitas 24: 222 232. This study used results from camera traps set for Dhole (Cuon alpinus) and their prey during 2017-2020 in Khao Yai National Park to assess the species richness of ground-dwelling birds and identify abundance and also temporal appearance of the species in the area. We selected only the Pheasant species that typically forage on the ground to investigate the physical factors affecting the appearance in Khao Yai National Park. Based on camera trapping data with a total of 4139 trap days, 115 camera locations showed 36 species of birds belonging to 21 families, and 13 orders of ground-dwelling bird species were recorded. Siamese Fireback (Lophura diardi), Red Junglefowl (Gallus gallus), and Silver Pheasant (Lophura nycthemera) were detected with an abundance index of 10.65%, 7.27%, and 1.84%, respectively. The ground-dwelling bird abundance index from the camera traps accounted for 26.85% of the total fauna. Although the Phasianidae were found to be diurnal species, this study also shows a statistically significant difference in the average time between Red Junglefowl and Siamese Fireback. Meanwhile, there was no statistically significant difference between Red Junglefowl and Silver Pheasant during their active time. The water sources showed a significant effect on the presence of the Siamese Fireback in data analysis; however, no physical environmental factors significantly affected the distribution of Red Junglefowl and Silver Pheasant. This study found that surrounding creeks and streams significantly impacted the appearance of the Siamese Fireback. As a result, area management needs to prevent and reduce disturbances along a creek in order to effectively manage the habitat of the Siamese Fireback and other wildlife.

Species diversity, abundance, and movement of small mammals in the dry evergreen forest at Khao Yai National Park, Thailand

Abstract. Chanachai Y, Nathalang A, Duengkae P, Sukmasuang R. 2022. Species diversity, abundance, and movement of small mammals in the dry evergreen forest at Khao Yai National Park, Thailand. Biodiversitas 23: 5892-5901. Small mammals play an integral role in the forest ecosystem. This research was conducted on The Mo Singto Forest Dynamics Plot, Khao Yai National Park. Trapping of small mammals was carried out in June-September 2019 and from January-April 2020 based on a total of 64 Tomahawk for small mammal live traps were systematically placed in an 8×8 grid of 20 m intervals, ripe bananas and palm oil as bait was used. Trap cages were opened for 3 consecutive months per season in each study period covering a total study period of 1 year. The result showed that a total of 4015 individuals from 9 species, 9 genera, 4 families and 3 orders were captured with a sampling effort of 32,555 trap nights. The most common species were Red Spiny Rat (Maxomys surifer), followed by Northern Tree Shrew (Tupaia belangeri), Long-tailed Giant Rat (Leopoldamys sabanus), Indochinese Ground Squirrel (Menetes berdmorei), Asian House Rat (Rattus tanezumi), Indomalayan Niviventer (Niviventer fulvescens), Savile's Bandicoot Rat (Bandicota savilei), (Tamiops mcclellandii), and Short-tailed Gymnure (Hylomys suillus) respectively. Considering the number of small mammals caught, Maxomys surifer was the most abundant, accounting for 61.69% of all mammals caught. The sex ratio was found to somewhat favor females in both seasons. This study indicated that the small mammal diversity was high in the primary dry evergreen forest. These results have important implications not only for conservation but are also useful for further investigation if there is any disturbance or change in the area or any potential disasters that may occur in the future.

Review: The status of the endangered Eld’s deer (Rucervus eldii) and conservation actions in Thailand

Abstract. Sukmasuang R, Bhumpakphan N, McShea WJ, Wajjwalku W, Siriaroonrat B, Kamolnoranart S, Yindee M, Nipanan T, Maleehuan B, Khanthathongsakuldee K, Pongcharoen C, Sutummawong N, Thomas W. 2022. Review: The status of the endangered Eld’s deer (Rucervus eldii) and conservation actions in Thailand. Biodiversitas 23: 5020-5034. The endangered Eld’s deer (Rucervus eldii) once roamed throughout the plains and dry forests of South and Southeast Asia. However, due to heavy poaching and habitat loss, the population has declined drastically and has disappeared from many of its historical ranges. They are presently found in some natural areas of India, Myanmar, Cambodia, Lao PDR, and Hainan Island, China. Thailand used to be the distribution center of the species, where two subspecies, the R.e. thamin and R.e. siamensis, were found. However, both subspecies have disappeared from the natural resources of Thailand since the early 1990s. Many conservation programs have been conducted to save this species in Thailand, such as captive breeding and reintroduction. Our literature review revealed that currently, more than a thousand R.e. thamin are housed in over 20 wildlife breeding facilities and 109 R.e. siamensis in 8 breeding facilities. Based on the workshops on conservation and restoration of the species, suitable genetic selection can create populations suitable for return to protected forest areas in Thailand. At present, more than 554 R.e. thamin have been released back into the wild in 8 wildlife sanctuaries, 3 national parks and 1 non-hunting area and 27 R.e. siamensis were released in 2 wildlife sanctuaries in Thailand. The follow-up of the deer in the release areas was flawed. Major knowledge gaps include recent trends in the population dynamics, habitat selection, diet items and threats. Identifying and restoring suitable dry forest habitats for reintroduction are also keys for species conservation.

Monetary evaluation of supporting ecosystem services as a habitat provider for birds in Thailand urban park

Abstract. Yarnvudhi A, Leksungnoen N, Siri S, Ponpithuk Y, Sukmasuang R, Duengkae P, Pongcharoen C, Sutummawong N, Marod D, Wachrinrat C, Premashthira A, Tor-ngern P, Poungcharean S, Hermuk S, Kachina P. 2022. Monetary evaluation of supporting ecosystem services as a habitat provider for birds in Thailand urban park. Biodiversitas 23: 4747-4758. Supporting services are important services to maintain ecosystems by providing habitats for organisms and genetic diversity. In this study, the monetary value of supporting services for bird habitats in urban parks was evaluated based on the price for nursing each bird species and market value. Bird diversity was conducted using point count observation. We found total of 53 bird species, 27 families and 8 orders in the park. Total monetary benefit for bird habitats in this park was estimated to be around USD60,354.12 per individual bird with an average value of USD1,138.76 per bird per species. The top three species with the highest monetary value were the Painted Stork (Mycteria leucocephala), Asian Openbill (Anastomus oscitans), and Chinese Pond Heron (Ardeola bacchus). The species diversity index of the bird community (H') was 2.73 and the most abundant bird species were Eastern Spotted Dove (Spilopelia chinensis), Eurasian tree sparrow (Passer montanus), Eastern jungle crow (Corvus levaillantii), Oriental magpie robin (Copsychus saularis), and Coppersmith Barbet (Psilopogon haemacephalus). Among 4 microhabitats, birds were found the most in the trees, followed by lawn, grassland, and wetland areas. The small urban parks should be designed with diverse microhabitats to provide various ecological functions to attract and ensure adequate resources for organisms.

Comparative sensitivity to environmental variation and human disturbance of Asian tapirs (Tapirus indicus) and other wild ungulates in Thailand

Southeast Asia's tropical forests suffer the highest rates of deforestation and disturbance of any on Earth, with poorly understood impacts on native fauna. Asian tapirs (Tapirus indicus) are among the least studied of the large mammals in these forests. Using records from 9 camera trap surveys in 7 of the largest (>1000 km(2) ) protected area complexes, we assessed the influence of environmental variation and human-induced disturbance on tapir occurrence. Tapirs were detected at 13% of locations sampled, significantly associated with evergreen forest (P < 0.001). A multiple logistic regression model predicted tapir presence 87% of the time. According to this model, tapir occurrence was positively influenced by annual rainfall and proximity to the forest edge. However, tapirs may not avoid edges but instead prefer wetter evergreen forest, a habitat type that tended to occur further from the forest edge at higher elevations in our particular study sites (P < 0.001). By comparison, 4 other wild ungulate species that share habitats with tapirs showed a range of differing responses. Tapirs are expected to be less sensitive to disturbance because they are not targets for hunting and trade, and are almost entirely active at night, so avoid peak traffic periods in parks. Tapir populations in Thailand may be more stable than in other parts of their global range because rates of forest loss have decreased >40% over the past 20 years. We recommend surveys to fill gaps in the understanding of the status in lesser-known protected areas, research to better understand the fine-scale environmental influences on behavior and habitats of tapirs, and other forest ungulates, and continued legal status for tapirs in the highest category of protection.