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The Endangered proboscis monkey Nasalis larvatus is endemic to the island of Borneo. Habitat loss is a major threat to this species, and an understanding of long-term demographic trends is crucial for its conservation. We assessed the population trends and group sizes of proboscis monkeys over 10 years in the Lower Kinabatangan floodplain in Sabah, Malaysian Borneo. Comparisons of observed populations between 2004 and 2014 revealed significantly reduced group sizes, which is probably a result of forest fragmentation. Three long-term studies over 34–73 months in specific areas showed fluctuating estimated densities in each area, but no overall population increase or decrease. Riparian forests are the most important habitat for these monkeys, and one reason for the relatively stable population could be that there were only minor losses of forest along rivers during 2004–2014 because protected areas have been established in the region in 2005. However, proboscis monkey habitat remains under threat in areas allocated for oil palm, and protection of these areas is paramount to maintaining this population.

With three species of orangutan now listed as Critically Endangered by the International Union for Conservation of Nature, orangutan conservation needs some critical rethinking. Habitat loss, degradation and fragmentation, and hunting are continuing to push orangutan populations towards further decline. Conservation efforts focusing on rehabilitation and habitat protection are in place but are insufficient unless we move towards a landscape approach that will aim at protecting and connecting areas rather than retaining isolated patches of forest. Conservationists need to engage with communities and industry to protect the species at a truly landscape level. This paper explores the current efforts in orangutan conservation on the ground and from the zoo community, and describes new areas emerging to contribute to these new approaches needed to impact positively wild orangutan populations.

In conservation, Collaboration is thought to improve returns from investment and is frequently encouraged, however not all collaborations are equal and may therefore lack characteristics important for addressing collective action problems. Furthermore, partnerships that are advantageous for a collective may not necessarily be advantageous for an individual. This study investigated collaboration within the Bornean orangutan (Pongo pygmaeus) conservation sector - a system with reported inefficiencies and for which there has been a renewed call for collaborative partnerships. Collaborative partnerships were conceptualised as a social network and analysed using exponential random graph modelling. The prevalence of structural attributes associated with social processes considered to be important for solving collective action problems such as trust and innovation were investigated. Qualitative surveying techniques were used to measure the perceptions of collaboration held by individual actors within the network and the impact of organizational attributes on network formation and perceptions was assessed. Collaboration was found to be occurring within the conservation network and was positively perceived at the individual organisational level. At the collective level, the current collaborative network contains some structural characteristics important for addressing the collective-action problem of orangutan conservation, particularly through innovation and knowledge sharing. However efforts to develop trust between organisations may be needed. To improve returns on investment, future collaborative partnerships must be strategically implemented with individual roles and desired overall outcomes explicitly articulated. Increased operational transparency and improved performance evaluation will be critical for achieving improved collaborative efficiency. © 2017 The Authors

Conflict between large-scale oil-palm producers and local communities is widespread in palm-oil producer nations. With a potential doubling of oil-palm cultivation in Indonesia in the next ten years it is likely that conflicts between the palm-oil industry and communities will increase. We develop and apply a novel method for understanding spatial patterns of oil-palm related conflicts. We use a unique set of conflict data derived through systematic searches of online data sources and local newspaper reports describing recent oil-palm land-use related conflicts for Indonesian Borneo, and combine these data with 43 spatial environmental and social variables using boosted regression tree modelling. Reports identified 187 villages had reported conflict with oil-palm companies. Spatial patterns varied with different types of conflict. Forest-dependent communities were more likely to strongly oppose oil-palm establishment because of their negative perception of oil-palm development on the environment and their own livelihoods. Conflicts regarding land boundary disputes, illegal operations by companies, perceived lack of consultation, compensation and broken promises by companies were more associated with communities that have lower reliance on forests for livelihoods, or are located in regions that have undergone or are undergoing forest transformation to oil-palm or industrial-tree-plantations. A better understanding of the characteristics of communities and areas where different types of conflicts have occurred is a fundamental step in generating hypotheses about why certain types of conflict occur in certain locations. Insights from such research can help inform land use policy, planning and management to achieve more sustainable and equitable development. Our results can also assist certification bodies (e.g. the Roundtable for Sustainable Palm Oil-RSPO, and the Indonesian and Malaysian versions, ISPO and MSPO), non-government-organisations, government agencies and other stakeholders to more effectively target mediation efforts to reduce the potential for conflict arising in the future.

For many threatened species, it is difficult to assess precisely for large areas the change in their abundances over time and the relative impacts of climate and anthropogenic land use. This is because surveys of such species are typically restricted to small geographic areas, are conducted during short time periods, and use different survey protocols. We assessed the change in the abundance of Bornean orangutanPongo pygmaeus morioin Sabah, Malaysia, and to identify environmental drivers affecting the change by integrating different types of survey data. We used nest count data obtained from aerial and ground transect surveys and occurrence data obtained from reconnaissance walks and interview survey over the past decade. We built a spatially-explicit dynamic population model within the Bayesian framework allowing these varying survey data to be analyzed jointly by explicitly accounting for each survey’s sampling rate. We found that sampling rates vary across survey types, reflecting each survey’s associated effort. Orangutan survival rates were strongly determined by natural forest extent and moderately by temperature. Orangutan migration rates across more than 1 km distance between forest patches were low, which underlines the importance of maintaining ecological connectivity. The paucity of species abundance data collected in a consistent manner over many years across broad extents often hinders the assessment of species population trend and their persistence across regional scales. We demonstrate that this can be addressed by integrating multiple survey data across different localities, provided that sampling rate inherent to each survey is accounted for.

We investigated the efficacy of a drone equipped with a thermal camera as a potential survey tool to detect wild Bornean orangutans (Pongo pygmaeus) and other tropical primates. Using the thermal camera we successfully detected 41 orangutans and a troop of proboscis monkeys, all of which were confirmed by ground observers. We discuss the potential advantages and limitations of thermal-equipped drones as a tool to complement other methods, and the potential of this technology for use as a future survey tool.

This work was supported by a research grant to K.J.H. from FCT, Portugal (PTDC/CS-ANT/121124/2010) and from MEXT, Japan (CCSN/PWS-U04). We are in a new epoch, the Anthropocene, and research into our closest living relatives, the great apes, must keep pace with the rate that our species is driving change. While a goal of many studies is to understand how great apes behave in natural contexts, the impact of human activities must increasingly be taken into account. This is both a challenge and an opportunity, which can importantly inform research in three diverse fields: cognition, human evolution, and conservation. No long-term great ape research site is wholly unaffected by human influence, but research at those that are especially affected by human activity is particularly important for ensuring that our great ape kin survive the Anthropocene. Postprint

The conversion of forest to agriculture continues to contribute to the loss and fragmentation of remaining orang‐utan habitat. There are still few published estimates of orang‐utan densities in these heavily modified agricultural areas to inform range‐wide population assessments and conservation strategies. In addition, little is known about what landscape features promote orang‐utan habitat use. Using indirect nest count methods, we implemented surveys and estimated population densities of the Northeast Bornean orang‐utan (Pongo pygmaeus morio) across the continuous logged forest and forest remnants in a recently salvage‐logged area and oil palm plantations in Sabah, Malaysian Borneo. We then assessed the influence of landscape features and forest structural metrics obtained from LiDAR data on estimates of orang‐utan density. Recent salvage logging appeared to have a little short‐term effect on orang‐utan density (2.35 ind/km 2), which remained similar to recovering logged forest nearby (2.32 ind/km 2). Orang‐utans were also present in remnant forest patches in oil palm plantations, but at significantly lower numbers (0.82 ind/km 2) than nearby logged forest and salvage‐logged areas. Densities were strongly influenced by variation in canopy height but were not associated with other potential covariates. Our findings suggest that orang‐utans currently exist, at least in the short‐term, within human‐modified landscapes, providing that remnant forest patches remain. We urge greater recognition of the role that these degraded habitats can have in supporting orang‐utan populations, and that future range‐wide analyses and conservation strategies better incorporate data from human‐modified landscapes., Research Highlights Forest remnants within oil palm estates can support substantial orang‐utan numbers, although at reduced density.Orang‐utan density is more influenced by forest structure than isolation from large forested areas in human‐modified landscapes of Borneo.

Tropical forests are globally important for both biodiversity conservation and the production of economically valuable wood products. To deliver both simultaneously, two contrasting approaches have been suggested: one partitions forests (sparing); the other integrates both objectives in the same location (sharing). To date, the ‘sparing or sharing’ debate has focused on agricultural landscapes, with scant attention paid to forest management. We explore the delivery of biodiversity and wood products in a continuum of sparing-to-sharing scenarios, using spatial optimization with set economic returns in East Kalimantan, Indonesia—a biodiversity hotspot. We found that neither sparing nor sharing extremes are optimal, although the greatest conservation value was attained towards the sparing end of the continuum. Critically, improved management strategies, such as reduced-impact logging, provided larger conservation gains than altering the balance between sparing and sharing, particularly for endangered species. Ultimately, debating sparing versus sharing has limited value while larger gains remain from improving forest management. To achieve both biodiversity conservation and timber production in tropical forests, this modelling study finds that improved management has much more impact than the choice between sparing forests or sharing forest land for both purposes.

The Bornean elephant population in Sabah, with only 2000 individuals, is currently mainly restricted to a limited number of forest reserves. The main threats to the species' survival are population fragmentation and isolation of the existing herds. To support and help monitor future conservation and management measures, we assessed the genetic diversity and population structure of Bornean elephants using mitochondrial DNA, microsatellites and single nucleotide polymorphisms. Our results confirmed a previously reported lack of mitochondrial control region diversity, characterized by a single widespread haplotype. However, we found low but significant degree of genetic differentiation among populations and marked variation in genetic diversity with the other two types of markers among Bornean elephants. Microsatellite data showed that Bornean elephants from the Lower Kinabatangan and North Kinabatangan ranges are differentiated and perhaps isolated from the main elephant populations located in the Central Forest and Tabin Wildlife Reserve. The pairwise FST values between these sites ranged from 0.08 to 0.14 (p

For more than 50 years, Critically Endangered Bornean orangutans (Pongo pygmaeus) have been rescued from poachers or captors, rehabilitated, and released into natural habitats. Wild orangutans are also translocated—intentionally captured from habitat patches and insecure situations for the purpose of releasing them into areas considered to be safer. Although these activities are widely applied, data on orangutan conservation and welfare effects are lacking. Our study improves understanding of these outcomes through analysis of Bornean orangutan rescues and releases conducted in Kalimantan, Indonesia between 2007 and 2017. We collected data on orangutan rescues (n = 1517) and releases (n = 1219) from rescue facility reports, newspaper articles, and scientific publications, and assessed outcomes in relation to action plans, international standards for wildlife releases, law enforcement, and wild orangutan population and habitat conservation. High levels of orangutan killing and illegal possession drove rescue facility intake, while deforestation, actual or potential human-orangutan interactions, and fires drove large-scale wild orangutan translocations. We found rescue facilities held 1112 orangutans in 2017, a number largely unchanged since 2007 despite 1219 reported releases including 605 ex-captive orangutans and a minimum of 523 translocated wild orangutans. Rescue has not facilitated notable changes in law enforcement, nor forestalled wild orangutan losses. Translocations in particular pose serious risks to conservation of orangutan metapopulations and individual welfare. Substantial changes in law enforcement, human attitudes and behaviors toward orangutans, and improved management of human-orangutan coexistence are needed to disrupt the current cycle of orangutan killing and illegal possession followed by rescue and release. These changes would enable a much-needed renewed focus on protecting wild orangutans in their natural habitats.

Examining how 70,000 years of human interaction shaped orangutans provides insights into conservation in the Anthropocene., Conservation benefits from understanding how adaptability and threat interact to determine a taxon’s vulnerability. Recognizing how interactions with humans have shaped taxa such as the critically endangered orangutan (Pongo spp.) offers insights into this relationship. Orangutans are viewed as icons of wild nature, and most efforts to prevent their extinction have focused on protecting minimally disturbed habitat, with limited success. We synthesize fossil, archeological, genetic, and behavioral evidence to demonstrate that at least 70,000 years of human influence have shaped orangutan distribution, abundance, and ecology and will likely continue to do so in the future. Our findings indicate that orangutans are vulnerable to hunting but appear flexible in response to some other human activities. This highlights the need for a multifaceted, landscape-level approach to orangutan conservation that leverages sound policy and cooperation among government, private sector, and community stakeholders to prevent hunting, mitigate human-orangutan conflict, and preserve and reconnect remaining natural forests. Broad cooperation can be encouraged through incentives and strategies that focus on the common interests and concerns of different stakeholders. Orangutans provide an illustrative example of how acknowledging the long and pervasive influence of humans can improve strategies to preserve biodiversity in the Anthropocene.

Unsustainable exploitation of natural resources is increasingly affecting the highly biodiverse tropics [1, 2]. Although rapid developments in remote sensing technology have permitted more precise estimates of land-cover change over large spatial scales [3–5], our knowledge about the effects of these changes on wildlife is much more sparse [6, 7]. Here we use field survey data, predictive density distribution modeling, and remote sensing to investigate the impact of resource use and land-use changes on the density distribution of Bornean orangutans (Pongo pygmaeus). Our models indicate that between 1999 and 2015, half of the orangutan population was affected by logging, deforestation, or industrialized plantations. Although land clearance caused the most dramatic rates of decline, it accounted for only a small proportion of the total loss. A much larger number of orangutans were lost in selectively logged and primary forests, where rates of decline were less precipitous, but where far more orangutans are found. This suggests that further drivers, independent of land-use change, contribute to orangutan loss. This finding is consistent with studies reporting hunting as a major cause in orangutan decline [8–10]. Our predictions of orangutan abundance loss across Borneo suggest that the population decreased by more than 100,000 individuals, corroborating recent estimates of decline [11]. Practical solutions to prevent future orangutan decline can only be realized by addressing its complex causes in a holistic manner across political and societal sectors, such as in land-use planning, resource exploitation, infrastructure development, and education, and by increasing long-term sustainability [12]. Video Abstract: [Figure presented] Voigt et al. show the negative impact of natural resource use on the density distribution of Bornean orangutans. The habitat of half of the population was affected. Over 16 years, more than 100,000 individuals were lost. Decline rates were highest when habitat was removed. Absolute losses were largest in selectively logged and primary forests.

Aim: We demonstrate a robust approach for predicting and mapping threats and population trends of wildlife species, invaluable for understanding where to target conservation resources. We used the endangered Bornean orangutan (Pongo pygmaeus) as our case study to facilitate and strengthen conservation efforts by the Indonesian government to stabilize populations by 2017. Location: Kalimantan, Indonesian Borneo. Methods: Local knowledge of threats to orangutan populations was gathered through questionnaire interviews in 531 villages (512 in Kalimantan) within known orangutan range. These data were integrated with 39 environmental/socio-economic spatial variables using boosted regression tree modelling to predict threat levels and population trends across Kalimantan and to identify key combinations of threats and trends that can help to direct appropriate conservation actions. Results: Nineteen percentage of villages surveyed in Kalimantan reported human-orangutan conflicts. High-predicted conflict likelihood was extensive, strongly associated with road density (very low or high) and temperature seasonality. Recent orangutan killings were reported in 23% of villages. High killing risk was highly associated with greater surrounding orangutan habitat and for villages more than 60 km from oil palm plantations. Killings by respondents were reported in 20% of villages with higher likelihoods associated with greater range in rainfall and temperature, and higher proportion of Christian believers. Orangutan populations were predicted to decline/become locally extinct across the majority of their range in Kalimantan over the next decade, with few regions predicted to support stable populations. Main conclusions: Human-orangutan conflicts and killings occur extensively in Kalimantan, with many populations at risk of decline or localized extinctions. Effective conservation actions are therefore urgently needed. Our approach better informs conservation managers in understanding the extent, spatial patterns and drivers of threats to endangered species such as the orangutan. This is essential to better design management strategies that can minimize or avert the species' decline.

For many threatened species the rate and drivers of population decline are difficult to assess accurately: species’ surveys are typically restricted to small geographic areas, are conducted over short time periods, and employ a wide range of survey protocols. We addressed methodological challenges for assessing change in the abundance of an endangered species. We applied novel methods for integrating field and interview survey data for the critically endangered Bornean orangutan (Pongo pygmaeus), allowing a deeper understanding of the species’ persistence through time. Our analysis revealed that Bornean orangutan populations have declined at a rate of 25% over the last 10 years. Survival rates of the species are lowest in areas with intermediate rainfall, where complex interrelations between soil fertility, agricultural productivity, and human settlement patterns influence persistence. These areas also have highest threats from human-wildlife conflict. Survival rates are further positively associated with forest extent, but are lower in areas where surrounding forest has been recently converted to industrial agriculture. Our study highlights the urgency of determining specific management interventions needed in different locations to counter the trend of decline and its associated drivers.

Although the importance of natural licks for terrestrial mammals is widely acknowledged, we report here for the first time its importance for large terrestrial mammals in a degraded riverine forest in Borneo. Our results clearly demonstrated that various mammals, including bearded pig, sambar deer, and endangered orang-utans, were using the natural lick, though large arboreal/avian herbivore/omnivore animals were not attracted to the natural lick. In addition, the diversity of mammal species recorded in this study was lower than those recorded in the dry lowland forest. Possible reasons for this difference between the different forest types are discussed.

The oil palm industry is blamed for the demise of iconic species such as the orang-utan Pongo pygmaeus in Borneo but production of, and demand for, this commodity continue to expand. Therefore, a better understanding of how the orang-utan is adapting to human-transformed environments is crucial for conserving the species. Results from a combination of repeated ground transects, aerial presence/absence surveys, and interviews of workers in mature plantations of the lower Kinabatangan River floodplain (eastern Sabah) provide an overall picture of the current status of orang-utans in an established agro-industrial oil palm landscape. Our results show that orang-utans disperse into mature plantations, use oil palm trees for nesting, and feed on mature fruits. Most oil palm workers report orang-utans of all age–sex classes within the estates but fail to report any negative effect of the animals on productivity of mature palms ≥5 years. Our surveys also show that orang-utan presence in the mature oil palm landscape is correlated with proximity to natural forest patches. These results suggest that forest patches, even when small, fragmented and degraded, are required to sustain the species in human-transformed landscapes. Homogenous oil palm plantations are incompatible with viable populations of orang-utans. The cessation of further forest conversion to agriculture and the enforcement of better management practices are needed to reduce the threat of oil palm development to orang-utan survival.

The plant vigour hypothesis proposes that herbivores should favour feeding on more vigorously growing plants or plant modules. Similarly, we would expect herbivores to favour plants that regrow vigorously after herbivory. Larger animals, like elephants, may also select plant species relative to their availability and prefer species with larger growth forms in order to meet their intake requirements. The food preferences of the Bornean elephant (Elephas maximus borneensis) in the Lower Kinabatangan Wildlife Sanctuary, Sabah, Malaysia, were investigated along 12 transects in areas where elephants were recently sighted feeding. One hundred and eighty-two plants were eaten and 185 plants were measured for species availability along transects. Species vigour was determined by the monthly regrowth in new shoot length after elephant feeding and the number of new shoots produced on each plant. Measurements were carried out on each plant for 9 mo or until the new shoot was eaten. Plant sizes were determined from their basal diameter. The Bornean elephant did not prefer more vigorous species or species with larger growth forms. New shoots did not grow longer on preferred than avoided species. Additionally, unlike other elephants that live in a forest environment, the Bornean elephant preferred species from the Poaceae (specifically Phragmites karka and Dinochloa scabrida) over other plant types including gingers, palms, lianas and woody trees.

Aim Habitat fragmentation threatens species’ persistence by increasing subpopulation isolation and vulnerability to stochastic events, and its impacts are expected to worsen under climate change. By reconnecting isolated fragments, habitat corridors should dampen the synergistic impacts of habitat and climate change on population viability. Choosing which fragments to reconnect is typically informed by past and current environmental conditions. However, habitat and climate are dynamic and change over time. Habitat suitability projections could inform fragment selection using current and future conditions, ensuring that corridors connect persistent fragments. We compare the efficacy of using current-day and future forecasts of breeding habitat to inform corridor placement under land cover and climate-change mitigation and no mitigation scenarios by evaluating their influence on subpopulation abundance, and connectivity and long-term metapopulation abundance. Our case study is the threatened orangutan metapopulation in Sabah. Location Sabah, Malaysian Borneo. Methods Using coupled niche–population models that capture a metapopulation distribution and its major processes, we forecast the effect of current-day and future-informed habitat corridor implementations under two scenarios where (1) land cover and climate change continue unabated (no mitigation) and (2) local and international cooperation mitigates their synergistic impact (mitigation). Results We show that Future-informed corridor placement maximizes long-term metapopulation abundance when human-driven land cover and climate change alter the spatio-temporal composition of suitable habitat. By contrast, there is no apparent benefit in using future forecasts of breeding habitat to inform corridor placement if conditions remain comparatively stable. For the Sabah orangutan under unabated land cover and climate change, habitat corridors should connect current-day populated eastern habitat fragments with vacant fragments in the state's west. Main conclusions The efficacy of habitat corridors can be improved by using habitat-suitability model projections to inform corridor placement in rapidly changing environments, even for long-lived, low-fecundity, philopatric species such as orangutan.

Spatially explicit information on local perceptions of ecosystem services is needed to inform land use planning within rapidly changing landscapes. In this paper we spatially modelled local people's use and perceptions of benefits from forest ecosystem services in Borneo, from interviews of 1837 people in 185 villages. Questions related to provisioning, cultural/spiritual, regulating and supporting ecosystem services derived from forest, and attitudes towards forest conversion. We used boosted regression trees (BRTs) to combine interview data with social and environmental predictors to understand spatial variation of perceptions across Borneo. Our results show that people use a variety of products from intact and highly degraded forests. Perceptions of benefits from forests were strongest: in human-altered forest landscapes for cultural and spiritual benefits; in human-altered and intact forests landscapes for health benefits; intact forest for direct health benefits, such as medicinal plants; and in regions with little forest and extensive plantations, for environmental benefits, such as climatic impacts from deforestation. Forest clearing for small scale agriculture was predicted to be widely supported yet less so for large-scale agriculture. Understanding perceptions of rural communities in dynamic, multi-use landscapes is important where people are often directly affected by the decline in ecosystem services.

A recent report, published by the Government of Indonesia with support from the Food and Agricultural Organization and Norway’s International Climate and Forest Initiative, states that orangutan populations (Pongo spp.) have increased by more than 10% in Indonesia from 2015 to 2017, exceeding the government target of an annual 2% population increase [1]. This assessment is in strong contrast with recent publications that showed that the Bornean orangutan (P. pygmaeus) lost more than 100,000 individuals in the past 16 years [2] and declined by at least 25% over the past 10 years [3]. Furthermore, recent work has also demonstrated that both Sumatran orangutans (P. abelii) and the recently described Tapanuli orangutan (P. tapanuliensis) lost more than 60% of their key habitats between 1985 and 2007, and ongoing land use changes are expected to result in an 11–27% decline in their populations by 2020 4, 5. Most scientific data indicate that the survival of these species continues to be seriously threatened by deforestation and killing 4, 6, 7 and thus all three are Critically Endangered under the International Union for Conservation of Nature’s Red List.

Each year an estimated US$20–30 million is spent by government and non-government organisations in efforts to conserve the Bornean orangutan. However, recent population analysis reveals that these efforts have been unable to reduce species decline. A major aim of the Indonesian National Action Plan for orangutan conservation is to “improve in-situ conservation as the principal activity ensuring the orangutan's survival in its native habitats”. This paper summarises and examines current investment in conservation activities and provides recommendations on the strategic allocation of funds for future conservation. The cost data of major conservation initiatives, including orangutan rescue and rehabilitation, habitat protection, habitat restoration and community education, was collated from non-government agency annual reports and primary literature. A recent population density and distribution model, and reports documenting the effectiveness of conservation strategies for the species were then used to calculate population trends in the presence and absence of interventions. Using an open-access cost-effectiveness resource allocator tool, we investigate expenditure and program performance. We then provide recommendations on how to strategically allocate conservation funding to future programs to ensure maximum effectiveness.

The United Nations’ Sustainable Development Goals underscore the need for improved understanding of relationships between changes in landscapes, livelihoods, and social welfare, and how these relate to tackling poverty, inequality, and environmental degradation. Such assessments are especially relevant in the context of oil palm agricultural expansion, which has rapidly replaced traditional livelihoods and generates ongoing political debates around the world. Proponents of the oil palm industry have used economic objectives to justify expansion, while opponents have raised the negative socioecological impacts on communities. To assist the debate, we assessed the association between the change in land-uses and climate, the change in village primary livelihoods towards monocultural oil palm cultivation, and the change in village welfare after adopting oil palm across Kalimantan, Indonesian Borneo, between 2000 and 2014. We show that the change in village primary livelihoods towards monocultural oil palm cultivation during this period was associated with complex interrelations between the expansion of agricultural industries, and conducive climate and market conditions for supporting agricultural production. The shift to oil palm monoculture brought significant economic benefit to villages, but this was limited to those with past exposure to plantation management and the market economy, such as in polyculture plantation villages. For villages where the majority of communities practiced traditional subsistence-based livelihoods (farming, foraging and fishing), the economic benefit from a shift to oil palm lasted only a few years after transition, while the socioecological welfare deteriorated. Furthermore, the shift to oil palm monoculture jeopardized food security among these subsistence livelihood villages. Baseline economic and socioecological conditions of villages, therefore, critically determine the success of the oil palm sector in providing economic benefits over the long term. Our study urgently calls for considering oil palm development objectives not only in terms of regional economic gain, but also the future maintenance of socioecological welfare of village communities.

Ebola virus disease (EVD) is a threat to human health and to the survival of African great apes. The disease has led to major population declines in chimpanzees Pan troglodytes and gorillas Gorilla gorilla, and infected great apes play an important role as sources of human EVD outbreaks. The threat posed by EVD raises the question whether vaccination of wild apes is an effective strategy to reduce the occurrence and impact of this disease. We review the current knowledge about EVD in great apes and document the link between outbreaks in apes and in humans, mainly via bushmeat consumption. We discuss the need for control strategies, such as vaccination, and describe aspects of primate behaviour, virus biology, vaccine composition, and vaccination principles that need to be considered when making management decisions about great ape vaccination. Finally, we identify gaps in the understanding of Ebola ecology and highlight surveillance and research that can aid the survival of great apes and reduce human exposure to Ebola virus. The severe impact of EVD indicates the need for efficient monitoring and, ultimately, control of Ebola. However, the unknown reservoir and unpredictable emergence of Ebola, the elusive nature of great apes, and the lack of licensed and suitable vaccines represent major hurdles for such control. Public education about zoonotic diseases and monitoring of great ape health are both important strategies. Experts should also discuss the feasibility of developing safe vaccines that can be delivered efficiently to large populations of elusive wild apes in their natural remote habitats. This review provides a platform for further interdisciplinary discussions, so that management plans can be discussed and adjusted according to possible future changes in the development, availability and cost of vaccines, the status of EVD, knowledge about Ebola ecology, and opinion on wildlife vaccination.

Balancing economic development with international commitments to protect biodiversity is a global challenge. Achieving this balance requires an understanding of the possible consequences of alternative future scenarios for a range of stakeholders. We employ an integrated economic and environmental planning approach to evaluate four alternative futures for the mega-diverse island of Borneo. We show what could be achieved if the three national jurisdictions of Borneo coordinate efforts to achieve their public policy targets and allow a partial reallocation of planned land uses. We reveal the potential for Borneo to simultaneously retain ∼50% of its land as forests, protect adequate habitat for the Bornean orangutan (Pongo pygmaeus) and Bornean elephant (Elephas maximus borneensis), and achieve an opportunity cost saving of over US$43 billion. Such coordination would depend on enhanced information sharing and reforms to land-use planning, which could be supported by the increasingly international nature of economies and conservation efforts., Balancing biological conservation with economic development is a challenge for policymakers. Analysing a range of possible future scenarios, Runting et al, show that coordinated planning would allow the island of Borneo to simultaneously retain forested land, protect species and meet economic goals.

Reducing Emissions from Deforestation and forest Degradation (REDD+) aims to avoid forest conversion to alternative land-uses through financial incentives. Oil-palm has high opportunity costs, which according to current literature questions the financial competitiveness of REDD+ in tropical lowlands. To understand this more, we undertook regional finescale and coarse-scale analyses (through carbon mapping and economic modelling) to assess the financial viability of REDD+ in safeguarding unprotected forest (30,173 ha) in the Lower Kinabatangan floodplain in Malaysian Borneo. Results estimate 4.7 million metric tons of carbon (MgC) in unprotected forest, with 64% allocated for oil-palm cultivations. Through fine-scale mapping and carbon accounting, we demonstrated that REDD+ can outcompete oil-palm in regions with low suitability, with low carbon prices and low carbon stock. In areas with medium oil-palm suitability, REDD+ could outcompete oil palm in areas\ud with: very high carbon and lower carbon price; medium carbon price and average carbon stock; or, low carbon stock and high carbon price. Areas with high oil palm suitability, REDD + could only outcompete with higher carbon price and higher carbon stock. In the coarse-scale model, oil-palm outcompeted REDD+ in all cases. For the fine-scale models at the landscape level, low carbon offset prices (US $3 MgCO2e) would enable REDD+ to outcompete oil-palm in 55% of the unprotected forests requiring US $27 million to secure these areas for 25 years. Higher carbon offset price (US $30 MgCO2e) would increase the competitiveness of REDD+ within the landscape but would still only capture between 69%-74% of the unprotected forest, requiring US $380–416 million in carbon financing. REDD+ has been identified as a strategy to mitigate climate change by many countries (including Malaysia). Although REDD+ in certain scenarios cannot outcompete oil palm, this research contributes to the global REDD+ debate by: highlighting REDD+ competitiveness in tropical floodplain landscapes; and, providing a robust approach for identifying and targeting limited REDD+ funds.

New plantations can either cause deforestation by replacing natural forests or avoid this by using previously cleared areas. The extent of these two situations is contested in tropical biodiversity hotspots where objective data are limited. Here, we explore delays between deforestation and the establishment of industrial tree plantations on Borneo using satellite imagery. Between 1973 and 2015 an estimated 18.7 Mha of Borneo’s old-growth forest were cleared (14.4 Mha and 4.2 Mha in Indonesian and Malaysian Borneo). Industrial plantations expanded by 9.1 Mha (7.8 Mha oil-palm; 1.3 Mha pulpwood). Approximately 7.0 Mha of the total plantation area in 2015 (9.2 Mha) were old-growth forest in 1973, of which 4.5–4.8 Mha (24–26% of Borneo-wide deforestation) were planted within five years of forest clearance (3.7–3.9 Mha oil-palm; 0.8–0.9 Mha pulpwood). This rapid within-five-year conversion has been greater in Malaysia than in Indonesia (57–60% versus 15–16%). In Indonesia, a higher proportion of oil-palm plantations was developed on already cleared degraded lands (a legacy of recurrent forest fires). However, rapid conversion of Indonesian forests to industrial plantations has increased steeply since 2005. We conclude that plantation industries have been the principle driver of deforestation in Malaysian Borneo over the last four decades. In contrast, their role in deforestation in Indonesian Borneo was less marked, but has been growing recently. We note caveats in interpreting these results and highlight the need for greater accountability in plantation development.

The impact of degradation of Southeast Asian rainforests and conversion to oil palm plantations on amphibians is unknown. To assess the relative value of secondary forests, oil palm plantations and other non-forest habitats for amphibian conservation, we evaluated amphibian species richness and assemblage composition in secondary lowland forests, compared with oil palm plantations and other non-forest habitats, along the Lower Kinabatangan River, eastern Sabah, Malaysia. Secondary forests retained a large proportion of amphibian species known from lowland primary rainforests. Species richness was higher in secondary forest habitats compared to oil palm plantations and other non-forest habitats. Secondary forests retained a much higher proportion of endemic species than non-forest habitats. We found strong differentiation between the frog assemblages in forest, non-forest and plantation sites. Oil palm plantations retained no microhylid species, few arboreal species and were dominated by habitat generalist and human commensal species. Our findings suggest that, despite a history of disturbance and degradation, remnant secondary forests may play an important role in conserving lowland amphibian diversity. In contrast, oil palm plantations have comparatively low conservation value for amphibians. Our study highlights the value of setting aside adequate areas of representative forest habitats within agricultural landscapes in order to conserve biodiversity, even when those remnants have a history of prior disturbance.

Orangutan survival is threatened by habitat loss and illegal killing. Most wild populations will disappear over the next few decades unless threats are abated. Saving orangutans is ultimately in the hands of the governments and people of Indonesia and Malaysia, which need to ensure that habitats of viable orangutan populations are protected fromdeforestationandwellmanagedtoensurenohuntingtakesplace.Companiesworkinginorangutanhabitatalso havetoplayamuchbiggerroleinhabitatmanagement.Althoughthemajorproblemsandthedirectactionsrequired to solve them—reducing forest loss and hunting—have been known for decades, orangutan populations continue to decline. Orangutan populations in Sumatra and Borneo have declined by between 2,280 and 5,250 orangutans annually over the past 25 years. As the total current population for the two species is some 60,000 animals in an area of about 90,000 km 2 , there is not much time left to make conservation efforts truly effective. Our review discusses what has and has not worked in conservation to guide future conservation efforts.

Tourism generates more than 9% of the global gross domestic product and may account for almost half of the gross domestic product in developing countries with biodiversity‐rich areas.1,2 Nature‐based tourism accounts for a growing proportion of international tourism activity. Ecotourism is a sustainable version of nature tourism with the following components: Ecotourism accounts for a significant proportion of all international tourism, and revenue generated by these activities could enhance economic opportunities for local residents, support environmental education, and protect the natural and cultural heritage of the area, including the conservation of biodiversity and improvement of local facilities.4 Ecotourism is increasingly seen as a means to promote wildlife conservation, increase public awareness, and raise revenue for protecting endangered species. Unfortunately, rapid, unmonitored development of ecotourism projects can lead to degradation of habitats and deleterious effects on animal well‐being. Habituation of animals to human presence can increase the likelihood that animals will actively seek out contact with humans, particularly in the form of crop raiding and invasion of garbage pits, latrines, and human households. Habituation may lead to alterations in animal stress responses, and this may lead to immunosuppression, increasing susceptibility to infectious diseases, and decreasing reproductive success. Other risks may include pollution, crowding, introduction of invasive species, and transmission of pathogens through direct and indirect infection routes. Zoonotic (nonhuman animal to human) and anthropozoonotic (human to nonhuman animal) infection transmission are of vital consideration, given the increasing demand from tourists to … Corresponding Author: Michael P. Muehlenbein, PhD, MsPH, Department of Anthropology, Indiana University, 701 E. Kirkwood Ave., Student Building 130, Bloomington, IN 47405‐7000, USA. E‐mail: mpm1{at}indiana.edu

Returning confiscated animals to their native habitats is desirable when it makes a positive contribution to the conservation of the species. Release of captive individuals is complex and controversial, however, particularly when risks are potentially high, as in the case of orphaned apes. We describe the decision-making process that led to the successive release of 20 wild-born orphan chimpanzees ( Pan troglodytes troglodytes) into the Conkouati Reserve in the Republic of Congo. Recommendations of the Reintroduction Specialist Group of the World Conservation Union's Species Survival Commission were followed closely. The conservation status, ecology, and behavior of wild chimpanzees; the biological, social, economic and political context of the release site; and the health and genetic status of the candidates for release were all taken into account in the planning and execution of the project. Rigorous post-release monitoring of behavior and health allowed documentation of the outcome. The project was of benefit to the chimpanzees that were released but also brought broad benefits to the site through effective protection from poaching and deforestation, and direct and indirect benefits to local people. The genetic and behavioral diversity of chimpanzees require a variety of conservation strategies to reduce threats and maintain as many viable wild populations as possible.

SummaryResponses of biodiversity to changes in both land cover and climate are recognized [1] but still poorly understood [2]. This poses significant challenges for spatial planning as species could shift, contract, expand, or maintain their range inside or outside protected areas [2–4]. We examine this problem in Borneo, a global biodiversity hotspot [5], using spatial prioritization analyses that maximize species conservation under multiple environmental-change forecasts. Climate projections indicate that 11%–36% of Bornean mammal species will lose ≥30% of their habitat by 2080, and suitable ecological conditions will shift upslope for 23%–46%. Deforestation exacerbates this process, increasing the proportion of species facing comparable habitat loss to 30%–49%, a 2-fold increase on historical trends. Accommodating these distributional changes will require conserving land outside existing protected areas, but this may be less than anticipated from models incorporating deforestation alone because some species will colonize high-elevation reserves. Our results demonstrate the increasing importance of upland reserves and that relatively small additions (16,000–28,000 km2) to the current conservation estate could provide substantial benefits to biodiversity facing changes to land cover and climate. On Borneo, much of this land is under forestry jurisdiction, warranting targeted conservation partnerships to safeguard biodiversity in an era of global change.

Behavioural observations suggest that orang-utans are semi-solitary animals with females being philopatric and males roaming more widely in search of receptive partners, leading to the prediction that females are more closely related than males at any given site. In contrast, our study presents evidence for male and female philopatry in the orang-utan. We examined patterns of relatedness and parentage in a wild orang-utan population in Borneo using noninvasively collected DNA samples from animals observed to defecate, and microsatellite markers to assess dispersal and mating strategies. Surprisingly, resident females were equally as related to other resident females (mean r(xy) = 0.303) as resident males were to other resident males (mean r(xy) = 0.305). Moreover, resident females were more related to each other and to the resident males than they were to nonresident females, and resident males were more related to each other (and resident females) than they were to nonresident males. We assigned genetic mothers to 12 individuals in the population, while sires could be identified for eight. Both flanged males and unflanged males achieved paternity, similar to findings reported for Sumatran orang-utans.

We report the results of eight years of post-release monitoring of 37 wild-born, captive chimpanzees released into the Conkouati-Douli National Park, Republic of Congo. Overall survival was high, with 23 (62%) individuals remaining in the release zone, and only 5 (14%) confirmed dead. Released females regularly interacted with wild chimpanzees. Several females appeared to have integrated into wild groups for extended periods of time, and four released females gave birth to a total of five offspring. However, encounters with wild chimpanzees were a major cause of mortality in released males, and 40–50% of released males would have died without veterinary intervention. These sex differences are in accordance with knowledge of chimpanzee behavioural ecology. Our results demonstrate that wild-born, captive chimpanzees can be released into the wild successfully, under certain specific conditions. Most importantly, careful planning and preparation is critical at all stages; a suitable release area must be identified; potential risks to existing wild populations, including the possibility of disease transmission, must be minimised; and post-release monitoring is essential. Adolescent females are the most suitable candidates for release, as they appear to be able to integrate successfully into wild communities. However, males should not be released where wild chimpanzees occur, as they are likely to be attacked and killed. Release into the wild addresses the welfare of certain individual animals, although it clearly cannot address the fate of all captive, wild-born chimpanzees. Knowledge of how to successfully release chimpanzees into the wild also has both current and potential future benefits for the conservation of wild chimpanzee populations.

We investigated the genetic structure within and among Bornean orang-utans ( Pongo pygmaeus ) in forest fragments of the Lower Kinabatangan flood plain in Sabah, Malaysia. DNA was extracted from hair and faecal samples for 200 wild individuals collected during boat surveys on the Kinabatangan River. Fourteen microsatellite loci were used to characterize patterns of genetic diversity. We found that genetic diversity was high in the set of samples (mean H E = 0.74) and that genetic differentiation was significant between the samples (average F ST = 0.04, P < 0.001) with F ST values ranging from low (0.01) to moderately large (0.12) values. Pairwise F ST values were significantly higher across the Kinabatangan River than between samples from the same river side, thereby confirming the role of the river as a natural barrier to gene flow. The correlation between genetic and geographical distance was tested by means of a series of Mantel tests based on different measures of geographical distance. We used a Bayesian method to estimate immigration rates. The results indicate that migration is unlikely across the river but cannot be completely ruled out because of the limited F ST values. Assignment tests confirm the overall picture that gene flow is limited across the river. We found that migration between samples from the same side of the river had a high probability indicating that orang-utans used to move relatively freely between neighbouring areas. This strongly suggests that there is a need to maintain migration between isolated forest fragments. This could be done by restoring forest corridors alongside the river banks and between patches.

Because of the difficulties encountered in detecting many large tropical forest-dwelling species in their natural habitat, precise figures concerning the distribution, number and trends of many populations remain deficient. In tropical forests, ground surveys are generally carried out by counting objects along straight lines. These counts require a strict compliance with the line-transect methodology before (proper design of the census), during (careful data collection) and after (accurate and correct data processing and analysis) the census itself. In addition, the major source of bias when estimating population size and/or trends comes from the extrapolation of estimates obtained in small sampling areas to the larger, and often incompletely known, distribution of the population. In the Kinabatangan floodplain (Sabah, Malaysia), helicopter surveys were useful in directly assessing the distribution of orang-utans and were a major advantage in the precise estimation of the size of the orang-utan population surviving in this region. Our survey showed that about 1100 orang-utans remain in the multiple-use forests of the Kinabatangan floodplain. These results provide new evidence on orang-utan adaptation to habitat disturbance and indicate the potential of the Kinabatangan multiple-use forests for orang-utan conservation. Helicopter surveys appear to be a promising alternative to ground survey for precise distribution assessment and for monitoring population trends of apes throughout their entire range in Asia and in some parts of Africa.

High concentrations of orangutans remain in the multiple-use forests of the Lower Kinabatangan, Sabah, Malaysia. Compared to primary forest, the habitat is highly fragmented, characterized by a low tree density (332 stems/ha), small tree size (83.6% of trees are

Geographic variation in some aspects of chimpanzee behavior has been interpreted as evidence for culture. Here we document similar geographic variation in orangutan behaviors. Moreover, as expected under a cultural interpretation, we find a correlation between geographic distance and cultural difference, a correlation between the abundance of opportunities for social learning and the size of the local cultural repertoire, and no effect of habitat on the content of culture. Hence, great-ape cultures exist, and may have done so for at least 14 million years.

Logging and poaching have dramatically reduced chimpanzee density and distribution in the Republic of Congo. Most chimpanzee translocations attempted in the past failed because a number of biological and non-biological factors can influence success. Biological considerations include knowledge of behaviour, disease, habitat requirements and genetics. We critically review genetic considerations in pre- and post-release phases of translocations and apply them to a welfare-based chimpanzee release project in the Republic of Congo which aimed to re-establish orphan chimpanzees in the wild with a native chimpanzee population. We analyze genetic diversity and relatedness in released animals and devise a genotyping strategy for monitoring of released individuals and their future offspring. Fifty-nine confiscated chimpanzees from different areas of the Republic of Congo were typed for 20 microsatellites using plucked hair as the DNA source. Genetic diversity was high, with an average expected heterozygosity of 81%, and three to 18 alleles per locus. Between 1996 and 1998, 19 individuals were released, and genetic analysis showed that these are unrelated (mean r± jack-knifed SD =−0.014 ± 0.001). Using FST and population admixture analysis, we identified population structure in wild chimpanzees. For long-term genetic monitoring of released and native chimpanzees, we identified a set of six informative markers, which are easy to score using basic techniques.

Balancing economic development with international commitments to protect biodiversity is a global challenge. Achieving this balance requires an understanding of the possible consequences of alternative future scenarios for a range of stakeholders. We employ an integrated economic and environmental planning approach to evaluate four alternative futures for the mega-diverse island of Borneo. We show what could be achieved if the three national jurisdictions of Borneo coordinate efforts to achieve their public policy targets and allow a partial reallocation of planned land uses. We reveal the potential for Borneo to simultaneously retain ∼50% of its land as forests, protect adequate habitat for the Bornean orangutan (Pongo pygmaeus) and Bornean elephant (Elephas maximus borneensis), and achieve an opportunity cost saving of over US$43 billion. Such coordination would depend on enhanced information sharing and reforms to land-use planning, which could be supported by the increasingly international nature of economies and conservation efforts.

The native forests of Borneo have been impacted by selective logging, fire, and conversion to plantations at unprecedented scales since industrial-scale extractive industries began in the early 1970s. There is no island-wide documentation of forest clearance or logging since the 1970s. This creates an information gap for conservation planning, especially with regard to selectively logged forests that maintain high conservation potential. Analysing LANDSAT images, we estimate that 75.7% (558,060 km2) of Borneo's area (737,188 km2) was forested around 1973. Based upon a forest cover map for 2010 derived using ALOS-PALSAR and visually reviewing LANDSAT images, we estimate that the 1973 forest area had declined by 168,493 km2 (30.2%) in 2010. The highest losses were recorded in Sabah and Kalimantan with 39.5% and 30.7% of their total forest area in 1973 becoming non-forest in 2010, and the lowest in Brunei and Sarawak (8.4%, and 23.1%). We estimate that the combined area planted in industrial oil palm and timber plantations in 2010 was 75,480 km2, representing 10% of Borneo. We mapped 271,819 km of primary logging roads that were created between 1973 and 2010. The greatest density of logging roads was found in Sarawak, at 0.89 km km-2, and the lowest density in Brunei, at 0.18 km km-2. Analyzing MODIS-based tree cover maps, we estimate that logging operated within 700 m of primary logging roads. Using this distance, we estimate that 266,257 km2 of 1973 forest cover has been logged. With 389,566 km2 (52.8%) of the island remaining forested, of which 209,649 km2 remains intact. There is still hope for biodiversity conservation in Borneo. Protecting logged forests from fire and conversion to plantations is an urgent priority for reducing rates of deforestation in Borneo.

The orangutan is the world's largest arboreal mammal and images of the red ape moving through the tropical forest canopy symbolise its typical arboreal behaviour. Records of terrestrial behaviour are scarce and often associated with habitat disturbance. We conducted a large-scale species-level analysis of ground-based camera-trapping data to evaluate the extent to which Bornean orangutans Pongo pygmaeus come down from the trees to travel terrestrially and whether they are indeed forced to the ground primarily by anthropogenic forest disturbances. Although the degree of forest disturbance and canopy gap size influenced terrestriality, orangutans were recorded on the ground as frequently in heavily degraded habitats as in primary forests. Furthermore, all age-sex classes were recorded on the ground (flanged males more often). This suggests that terrestrial locomotion is part of the Bornean orangutan's natural behavioural repertoire to a much greater extent than previously thought and is only modified by habitat disturbance. The capacity of orangutans to come down from the trees may increase their ability to cope with at least smaller-scale forest fragmentation and to cross moderately open spaces in mosaic landscapes, although the extent of this versatility remains to be investigated.

We investigated why orangutans are being killed in Kalimantan, Indonesia, and the role of conflict in these killings. Based on an analysis of interview data from over 5,000 respondents in over 450 villages, we also assessed the socio-ecological factors associated with conflict and non-conflict killings. Most respondents never kill orangutans. Those who reported having personally killed an orangutan primarily did so for non-conflict reasons; for example, 56% of these respondents said that the reason they had killed an orangutan was to eat it. Of the conflict-related reasons for killing, the most common reasons orangutans were killed was fear of orangutans or in self-defence. A similar pattern was evident among reports of orangutan killing by other people in the villages. Regression analyses indicated that religion and the percentage of intact forest around villages were the strongest socio-ecological predictors of whether orangutans were killed for conflict or non-conflict related reasons. Our data indicate that between 44,170 and 66,570 orangutans were killed in Kalimantan within the respondents’ active hunting lifetimes: between 12,690 and 29,024 for conflict reasons (95%CI) and between 26,361 and 41,688 for non-conflict reasons (95% CI). These findings confirm that habitat protection alone will not ensure the survival of orangutans in Indonesian Borneo, and that effective reduction of orangutan killings is urgently needed.