Population and distribution of wild Asian elephants (Elephas maximus) in Phu Khieo Wildlife Sanctuary, Thailand

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.

The Preferred Habitat of Reintroduced Banteng (Bos javanicus) at the Core and the Edge of Salakphra Wildlife Sanctuary, Thailand

Monitoring of banteng (Bos javanicus) after reintroduction is important for their management. This study aimed to monitor the preferred habitat and area of use of reintroduced banteng at the core (13 banteng) and the edge (three banteng) of Salakphra Wildlife Sanctuary between 2019 and 2021 and compared the finding with previous studies conducted from 2014 to 2019. The Binary Logistic Regression (BLR) showed the most preferred, moderately preferred, and least preferred areas were 44.7 km², 1.2 km², and 54.1 km² in the dry season, and 25.9 km², 1.0 km², and 9.3 km² in the wet season, respectively. Maximum Entropy (MaxEnt) showed the most preferred, moderately preferred, and least preferred areas as 12.1 km², 17.3 km², and 65.9 km², respectively. Banteng have previously been found close to ponds and salt licks. The area of use size, as determined by Minimum Convex Polygon (MCP) and Kernel Density Estimation (KDE), was 20.3 km² and 6.5 km², respectively. Three banteng were reintroduced to the edge area in 2020. The edge area was temporarily utilized by these individuals. In the core area, the area of use in this study decreased compared to the previous studies from 2014 to 2019, indicating they were able to find their preferred habitat. This study suggested that, if the area is managed appropriately, banteng will be able to live in a smaller habitat, and we will be able to restore the banteng population in the future.

Young elephants in a large herd maintain high levels of elephant endotheliotropic herpesvirus-specific antibodies and do not succumb to fatal haemorrhagic disease

Elephant endotheliotropic herpesviruses (EEHVs) have co-existed with elephants for millions of years, yet may cause fatal haemorrhagic disease (EEHV-HD), typically in elephants between 1 and 10 years of age. EEHV is omnipresent in (sub)adult elephants, and young elephants with low EEHV-specific antibody levels are at risk for EEHV-HD, suggesting that fatal disease may occur due to an insufficiently controlled primary infection. To further address this hypothesis, sera of three large elephant cohorts were subjected to a multiple EEHV species ELISA: (I) 96 Asian elephants between 0 and 57 years, including 13 EEHV-HD fatalities, from European zoo herds typically sized five to six elephants, (II) a herd of 64 orphaned elephants aged 0-15 years at the Elephant Transit Home in Sri Lanka and (III) 31 elephants aged 8-63 years, part of a large herd of 93 elephants at Pinnawala Elephant Orphanage, Sri Lanka. All Sri Lankan elephants showed high EEHV-specific antibody levels regardless of their age. While antibody levels of most European zoo elephants were comparable to those of Sri Lankan elephants, the average antibody level of the European juveniles (1-5 years of age) was significantly lower than those of age-matched Sri Lankan individuals. Moreover, the European juveniles showed a gradual decrease between 1 and 4 years of age, to be attributed to waning maternal antibodies. Maintenance of high levels of antibodies in spite of waning maternal antibodies in young Sri Lankan elephants is likely due to the larger herd size that increases the likelihood of contact with EEHV-shedding elephants. Together with the observation that low levels of EEHV-specific antibodies correlate with increased numbers of EEHV-HD fatalities, these results suggest that infection in presence of high maternal antibody levels may protect calves from developing EEHV-HD, while at the same time activating an immune response protective in future encounters with this virus.

Human-elephant conflict risk assessment under coupled climatic and anthropogenic changes in Thailand

As natural resources decrease, competition between humans and large endangered wildlife increases, hindering the sustainability of animal conservation and human development. Despite the multi-dimensional nature of such interactions, proactive assessments that consider both the biosphere and anthroposphere remain limited. In this study, we proposed a human elephant conflict risk assessment framework and analyzed the spatial distribution of risk at the baseline (2000-2019) and in the near future (2025-2044) for Thailand, so that it may address the multifaceted characteristics and impending effects of climate change. Future scenarios were based on the combination of RCP45/SSP2 or RCP85/SSP5 and spatial policy, with or without elephant buffer zones. The composite risk index, comprised of hazard, exposure, and vulnerability, was constructed using the geometric mean, and validation was performed with the area under the curve (AUC). Our results projected a shift with increasing future risk toward higher latitudes and altitudes. Increasing future risk (average +1.7% to +7.4%) in the four forest complexes (FCs) in northwestern regions was a result of higher hazard and vulnerability from more favorable habitat conditions and increasing drought probability, respectively. Reduction in future risk (average -3.1% to -57.9%) in other FCs in lower regions was mainly due to decreasing hazard because of decreasing habitat suitability. Our results also highlight geographically explicit strategies to support long-term planning of conservation resources. Areas with increasing future risk are currently facing low conflict; hence it is recommended that future strategies should enhance adaptive capacity and coexistence awareness. Conversely, areas with lowering future risk from a decrease in habitat quality are recommended to identify buffer strategies around protected areas to support existing large elephant populations.

Preference Heterogeneity of Local Participation in Coupling Conservation and Community-Based Entrepreneurship Development

The aims of conservation and economic prosperity for people living near protected areas have rapidly acquired prominence as a viable strategy for global biodiversity protection. To identify potential local enterprise improvement, we examine how rural communities adopt integrated conservation and development programs. Choice experiments are used to establish villagers’ preferences for conservation incentives. The incentive structure as well as attitudes regarding ecosystem services are being investigated. The latent class technique was used to estimate preference parameters, which resulted in two segments that accounted for villager heterogeneity. These segments were discovered through program restrictions, each with different resource usage, time spent, and compensation. Members of the more restrictive program desire a higher reward for participation in one program over another. Attitudes toward provisioning and regulating ecosystem services influence their engagement. The findings show that the younger generation is open to less restrictive programs and sharing resources to boost community enterprises. They are prepared to forego a few hours of farming in exchange for conservation actions. Programs that allow for flexibility in conservation regulations and other program features may be the most effective way to encourage more people to participate in conservation programs while also satisfying community goals.

Differential Impacts of Climatic and Land Use Changes on Habitat Suitability and Protected Area Adequacy across the Asian Elephant’s Range

Climate change and human activities have caused dramatic impacts on biodiversity. Although a number of international agreements or initiatives have been launched to mitigate the biodiversity loss, the erosion of terrestrial biome habitats is inevitable. Consequently, the identification of potential suitable habitats under climate change and human disturbance has become an urgent task of biodiversity conservation. In this study, we used the maximum entropy model (MaxEnt) to identify the current and potential future habitats of Asian elephants in South and Southeast Asia. We performed analyses for future projections with 17 scenarios using the present results as baseline. To optimize the modelling results, we delineated the core habitats by using the Core Mapper Tool and compared them with existing protected areas (PAs) through gap analysis. The results showed that the current total area of core habitats is 491,455 km2 in size and will be reduced to 332,544 km2 by 2090 under SSP585 (the shared socioeconomic pathway). The projection analysis under differential scenarios suggested that most of the core habitats in the current protected areas would remain stable and suitable for elephants in the future. However, the remaining 75.17% of the core habitats lay outside the current PAs, and finally we mapped approximately 219,545 km2 of suitable habitats as priority protected areas in the future. Although our model did not perform well in some regions, our analyses and findings still could provide useful references to the planning of protected areas and conservation of Asian elephant.