Nadine Ruppert

Universiti Sains Malaysia | USM · School of Biological Sciences

Citizen science‐based research has been used effectively to estimate animal abundance and breeding patterns, to monitor animal movement, and for biodiversity conservation and education. Here, we evaluate the feasibility of using social media observations to assess the distribution of small apes in Peninsular Malaysia. We searched for reports of sma...

Palm oil (PO) is an important source of livelihood, but unsustainable practices and widespread consumption may threaten human and planetary health. We reviewed 234 articles and summarized evidence on the impact of PO on health, social and economic aspects, environment, and biodiversity in the Malaysian context, and discuss mitigation strategies bas...

Roads negatively affect wildlife populations globally, causing habitat fragmentation that can facilitate mortality by access to forest for poaching and wildlife collisions with vehicles. Primate habitats are vulnerable to fragmentation exposing them to anthropogenic threats. Endangered dusky langurs (Trachypithecus obscurus) in Malaysia are often f...

Interspecific hybridization in primates is common but hybridization between distantly related sympatric primate species is rarely observed in the wild. We present evidence for a possible hybridization event between Nasalis larvatus and Trachypithecus cristatus in the Lower Kinabatangan Wildlife Sanctuary, Sabah, through assessment of photographs. W...

Small ape habitat throughout Malaysia is rapidly being lost, degraded, and fragmented, and the effects of these changes on the abundance on this taxon are currently unknown. This study assessed the group density of Hylobates agilis in virgin forest, previously logged forest (1960s-1990s), and recently logged forest (2015-2017) of the Ulu Muda Fores...

Accurately estimating population sizes for free-ranging animals through noninvasive methods, such as camera trap images, remains particularly limited by small datasets. To overcome this, we developed a flexible model for estimating upper limit populations and exemplified it by studying a group-living synanthrope, the long-tailed macaque ( Macaca fa...

Western hoolock gibbons (Hoolock hoolock) are generally regarded as socially monogamous, with strong pair-bonds leading to the maintenance of close spatial cohesion. Limited mate choice in isolated populations may, however, affect their social and reproductive behavior. We observed an isolated small population of western hoolock gibbons in Saltila,...

Considering the growing global biodiversity crisis, citizen science initiatives have emerged as powerful tools for long-term ecological data collection involving non-experts in research. “USM Campus Nature Challenge”, a collaborative effort led by the USM Library in partnership with the School of Biological Sciences and the Centre for Global Sustai...

Most conservation research and efforts focus on a targeted animal taxon and we often tend to forget about the human component in conservation work. It is often alleged that conservation work is in itself rewarding, rather than motivated by monetary gain. However, this remains anecdotal, and this study approaches this topic through qualitative analy...

Nocturnal mammals constitute a crucial component of tropical faunal diversity, but not much is known about the effects of anthropogenic disturbance on the habitat use and detectability of these species. We investigated which habitat and environmental variables impact the detectability of non-volant nocturnal arboreal mammals across varying habitat...

The Western Hoolock Gibbon (Hoolock hoolock) is a Critically Endangered primate species in Bangladesh and Endangered globally. Gibbon habitats of Bangladesh are rapidly declining due to habitat loss and degradation, illegal encroachments, expansions of agriculture including traditional practices (jhoom), betel leaf plantations, and monoculture. Hun...

The expansion of transportation and service corridors has numerous, well-documented adverse effects on wildlife. However, little research on this topic has been translated into mitigating the effects of habitat fragmentation caused by road development on primates. The establishment of canopy bridges has proven to be an effective conservation interv...

A growing number of studies have investigated the evolutionary drivers of external eye appearance in primates, but conclusive evidence is lacking. The literature has distinguished between two types of functions. Communicative functions, such as announcing a tame temperament via conjunctival depigmentation, and photo-regulatory functions towards the...

We conducted a community-based conservation approach using semi-structured interviews with local communities, wildlife enthusiasts and local forest department staff to assess the gibbon population status and primate hunting in selected sites in Bangladesh from January 2018 to June 2022.

In 2022, long‐tailed macaques (Macaca fascicularis), a once ubiquitous primate species, was elevated to Endangered on the International Union for Conservation of Nature (IUCN) Red List of Threatened Species. In 2023, recognizing that the longtailed macaque is threatened by multiple factors: (1) declining native habitats across Southeast Asia; (2) o...

A number of isolated patches of forest in Malaysia are understudied but potentially host a high species diversity and endemism. The aim of this study was to assess the presence of mammal species at different locations on the limestone hills located at Batu Caves, Selangor. We undertook transects walks along trails in two locations around the hill f...

In 2022, long-tailed macaques (Macaca fascicularis), a once ubiquitous primate species, was elevated to Endangered on the International Union for Conservation of Nature (IUCN) Red List of Threatened Species. In 2023, recognizing that the long-tailed macaque is threatened by multiple factors: (1) declining native habitats across Southeast Asia; (2)...

Small ape habitat is rapidly declining due to anthropogenic activities but the current population status of this endangered primate family in Malaysia remains unknown. Group densities of Hylobates lar and Symphalangus syndactylus in two adjacent forest reserves across the Sungai Yu Ecological Corridor (SYEC) in Merapoh, a critical connectivity area...

The IUCN Red List assessment of Macaca fascicularis 2022

IUCN Red List assessment of Macaca nemestrina

With the rationale above, we suspect the species has experienced a decline of at least 40% over the last three generations (approximately 40 years). We also suspect that the rates of decline are increasing as threats have increased and we suspect the species will experience at least a 50% decline in the coming three generations. Therefore, we asses...

Deforestation is a major threat to terrestrial tropical ecosystems, particularly in Southeast Asia where human activities have dramatic consequences for the survival of many species. However, responses of species to anthropogenic impact are highly variable. In order to establish effective conservation strategies, it is critical to determine a speci...

Abstract: In primates, observations of interspecies grooming are not uncommon, especially between species of the same genus. However, little is reported about grooming between different genera and less is discussed about its ecological significance. Here, we report the first sighting of Long-tailed Macaques grooming the Critically Endangered and ra...

Human population expansion into wildlife habitats has increased interest in the behavioural ecology of human–wildlife interactions. To date, however, the socioecological factors that determine whether, when or where wild animals take risks by interacting with humans and anthropogenic factors still remains unclear. We adopt a comparative approach to...

In this study we assessed the non-volant mammal diversity of Penang Hill by combining three methodologies: live cage trapping at ground level, camera trapping at ground and canopy level, and night survey walks using a FLIR thermal device. We recorded a total of 18 species of small, non-volant mammals at the study site, of which one is listed as Cri...

Sheikh Jamal Inani National Park (Inani) is a wildlife habitat in Bangladesh located under the Cox’s Bazar South Forest Division, Cox’s Bazar. It constitutes significant habitat for the charismatic and globally ‘Endangered’ Western Hoolock Gibbon Hoolock hoolock in Bangladesh. Here, we show that Inani is a poorly-known gibbon habitat with a populat...

Human-induced habitat alterations globally threaten animal populations, often evoking complex behavioural responses in wildlife. This may be particularly dramatic when negatively affecting social behaviour, which fundamentally determines individual fitness and offspring survival in group-living animals. Here, we provide first evidence for significa...

Human population expansion into wildlife habitats has increased interest in the behavioral ecology of human-wildlife interactions. To date, however, the socio-ecological factors that determine whether, when or where wild animals take risks by interacting with humans and anthropogenic factors still remains unclear. We adopt a comparative approach to...

Despite increasing conflict at human-wildlife interfaces, there exists little research on how the attributes and behavior of individual wild animals may influence human-wildlife interactions. Adopting a comparative approach, we examined the impact of animals' life-history and social attributes on interactions between humans and (peri)urban macaques...

Human-induced habitat alterations globally threaten animal populations, often evoking complex behavioural responses in wildlife. This may be particularly dramatic when negatively affecting social behaviour, which fundamentally determines individual fitness and offspring survival in group-living animals. Here, we provide first evidence for critical...

Human-induced habitat alterations globally threaten animal populations, often evoking diverse and complex behavioural responses in wildlife. This may be particularly dramatic when negatively affecting social behaviour, which fundamentally determines individual fitness and offspring survival in group-living animals. Here, we provide first evidence f...

Rattan spines are most often regarded as an identification trait and perhaps as a physical protection structure. In this study, we study the spinescence traits from five different species rattan: Daemonorops lewisiana, Daemonorops geniculata, Calamus castaneus, Plectomia griffithii, and Korthalsia scortechinii. We tested length, width, angle, stren...

The emergence of SARS-CoV-2 in late 2019 and human responses to the resulting COVID-19 pandemic in early 2020 have rapidly changed many aspects of human behavior, including our interactions with wildlife. In this commentary, we identify challenges and opportunities at human-primate interfaces in light of COVID-19, focusing on examples from Asia, an...

An updated list of Malaysian primates adapted from Lappan, S. & Ruppert, N. (2019). Primate research and conservation in Malaysia. CAB Reviews 14(4):1-10. DOI: 10.1079/PAVSNNR201914004, with information about areas of occurrence, IUCN Red List categories, and primary threats.

Anthropogenically disturbed areas may sometimes be as diverse as non-disturbed areas. We studied the distribution of nocturnal primates in Peninsula Malaysia and Brunei Darussalam. We focused on three species; the Sunda slow loris (Nycticebus coucang), the Philippine slow loris (Nycticebus menagensis) and the Horsfield’s tarsier (Cephalophacus banc...

Flying squirrels are poorly studied nocturnal mammals as their elusive and nocturnal behaviour makes it hard to observe them in the wild. Here, we describe sightings of Petaurista petaurista on a limestone hill and its foot at Merapoh, Pahang, Malaysia. This is the first report as the species is usually known to inhabit forest habitat. We observed...

The rising demand for electricity has pushed at the boundaries of forest reserves to make way for hydroelectric dams, particularly in Malaysia, a country with a rapidly growing socioeconomic sector. Hydroelectric dams reduce forest habitats and displace animals, particularly small and medium-sized mammals, which are often overlooked. A study was co...

The rising demand for electricity has pushed at the boundaries of forest reserves to make way for hydroelectric dams, particularly in Malaysia, a country with a rapidly growing socioeconomic sector. Hydroelectric dams reduce forest habitats and displace animals, particularly small and medium-sized mammals, which are often overlooked. A study was co...

In primates, living in an anthropogenic environment can significantly improve an individual's fitness, which is likely attributed to access to anthropogenic food resources. However, in non-professionally provisioned groups, few studies have examined whether individual attributes, such as dominance rank and sex, affect primates' ability to access an...

Conventional ground monitoring of protected areas are commonly being conducted by foot or using light aircrafts. Time, financial ability, energy, and safety are some of the main concerns during monitoring large landscapes. Monitoring of orangutans during night-time was arduous using conventional observation method. This study described the detectio...

Conversion of tropical forests into oil palm plantations reduces the habitats of many species, including primates, and frequently leads to human–wildlife conflicts. Contrary to the widespread belief that macaques foraging in the forest–oil palm matrix are detrimental crop pests, we show that the impact of macaques on oil palm yield is minor. More i...

Roads enable us to access various parts of our country by driving, cycling and walking. However, road development without proper consideration of wildlife movement may cause problems such as road kills, accidents and human-wildlife conflicts. Especially in urban environments, wildlife struggles to move between fragmented habitats and is challenged...

Most primates are threatened but studies that address their use of degraded habitats are scarce. Here, we report on activities, habitat use and diet of Trachypithecus obscurus in a human-impacted landscape in Penang Island. We studied the relationship of these primates with their habitat to facilitate conservation management plans. We used group sc...

Rattan is an important climbing palm taxon in Malaysian tropical rain forests. Many rattan species have unique structures directly associated with certain ant species. In this study, four rattan species (Daemonorops lewisiana, Calamus castaneus, Daemonorops geniculata and Korthalsia scortechinii) were inspected and documented in a field survey conc...

The rise of palm oil as the world's most consumed vegetable oil has coincided with exponential growth in palm oil research activity. Bibliometric analysis of research outputs reveals a distinct imbalance in the type of research being undertaken, notably a disproportionate focus on biofuel and engineering topics. Recognizing the expansion of oil pal...

Here, we reiterate the importance of the expert bioblitz to advance conservation, as championed in the excellent article by Parker et al. (2018). We contribute three additional ideas to their advances, using our own case study of a recent bioblitz in Malaysia: (a) prioritize inclusivity of diverse participants and stakeholders; (b) execute whole‐fo...

The rise of palm oil as the world’s most consumed vegetable oil has coincided with exponential growth in palm oil research activity. Bibliometric analysis of research outputs reveals a distinct imbalance in the type of research being undertaken, notably a disproportionate focus on biofuel and engineering topics. Recognising the expansion of oil pal...

Urbanization causes loss of wildlife habitats. In Penang Island, especially primates are threatened by habitat loss and fragmentation. They can often be observed feeding by the roadside, in residential areas, orchards or plantations. This may cause conflicts as wildlife moves into residential areas but it also poses a risk to the animals who are ex...

Keywords: anthropogenic environment humanewildlife interactions nonhuman primates social interactions stress time constraints Humans and their associated anthropogenic factors may strongly affect the demographics, activity and fragmentation of wild animal populations. Yet, the degree and nature of such impact on indicators of animals' social relati...

Malaysia is inhabited by ≥25 nonhuman primate species from five families, one of the most diverse primate faunas on earth. Unfortunately, most Malaysian primates are threatened with extinction due to habitat loss, degradation, and fragmentation, hunting and the synergies among these processes. Here, we review research on primates and issues related...

Here, we reiterate the importance of the expert bioblitz to advance conservation, as championed in the excellent article by Parker et al. (2018). We contribute three additional ideas to their advances, using our own case study of a recent bioblitz in Malaysia: (a) prioritize inclusivity of diverse participants and stakeholders; (b) execute whole‐fo...

Until now, mother-infant relationships have not been studied in a wild population of the Southern Pig-tailed Macaques Macaca nemestrina. We observed six mother-infant dyads from April 2016 to September 2016 in the Segari Melintang Forest Reserve, Peninsular Malaysia using focal sampling methods from the perspectives of both individuals. We hypothes...

Magazine article SCIENCE NEWS https://www.sciencenews.org/article/malaysia-pig-tail-macaques-eat-rats-head-first

https://www.nst.com.my/lifestyle/pulse/2018/07/392792/monkey-matters

Until now, mother-infant relationships have not been studied in a wild population of Southern pig-tailed macaques Macaca nemestrina (Linnaeus). We observed six mother-infant dyads from April 2016 to September 2016 in the Segari Melintang Forest Reserve, Perak, Peninsular Malaysia using focal sampling methods from the perspectives of both individual...

The nest is one of the crucial elements in orangutan daily activities. Previously, most of the nest structure studies were done manually by estimating measurement directly from visual observation. However, using the latest unmanned aerial vehicle (UAV) technology, we can reduce the workforce, time and energy while simultaneously ensuring the safety...

Malaysia is a biodiversity hot spot with high primate diversity but still loses large parts of its natural habitat to new oil palm plantations [A]. These notably change the composition, availability and distribution of natural food resources for a wide range of tropical forest species, and introduce an anthropogenic food source, which may fuel huma...

Recent reports of the use of ultrasound for communication by nocturnal mammals have expanded our understanding of behaviour in these animals. The vocal repertoire of colugos has so far only been known to include audible sound. Here, we report the use of ultrasound calls by Sunda colugos (Galeopterus variegatus, order Dermoptera). We recorded one ty...

Conversion of primary rainforest to agricultural land causes habitat loss and fragmentation and is a major threat to wild primates worldwide. Conversion of forest to oil palm plantations (Elaeis guineensis) is a particular problem, so it is important to understand whether and how primates use such plantations. Populations of southern pig-tailed mac...

2nd progress report Rufford Small Grant 2017

Pigtailed macaques in oil palm-pest or pest control? We have been running an extensive mark and recapture study of oil palm plantation rats within and outside the home range of our macaque focal group since March 2017 (Fig. 1). We chose three different trapping plots within the foraging area of the pigtailed macaques (30 wire mesh life traps spaced...

We conducted a preliminary assessment of distribution and behaviours of Macaca fascicularis and Trachypithecus obscurus by line-transect survey and group scan data collection at the northeastern part of Penang National Park (PNP), Malaysia. We encountered four groups of M. fascicularis (group sizes 8-19 individuals) and four groups of T. obscurus (...

Environmental enrichment is essential for the psychological and physical well-being of captive animals. Food enrichment was shown to promote foraging and positive social behaviors in apes. We provided environmental enrichment for four captive Bornean orangutans (Pongo pygmaeus) at Taiping Zoo & Night Safari, Perak, Malaysia from January to February...

Amorphophallus bufo is a rarely studied plant in Malaysian tropical rainforests. We measured the spectral reflectance of different developmental stages of A. bufo (seedlings, juveniles and adults), background soil/ debris and leaves from other neighboring plant species. Results show that the leaves of A. bufo seedling have a similar reflectance cur...

We have initiated an effort to evaluate the conservation status of small apes throughout Peninsular Malaysia. In light of the paucity of current information on gibbon populations, citizen science collaboratives and other online observation records represent a potential repository for up-to-date information on gibbon populations. These methods may b...

Rattans (subfamily Calamoideae) are an important component of the forests of the Old World. However, few studies have been conducted on the distribution of these abundant palms within different habitats, specifically in Peninsular Malaysia. This study was aimed at assessing rattan diversity, abundance and biomass change across two different habitat...

The dusky leaf monkey or spectacled langur (Trachypithecus obscurus) is a common primate species of Peninsular Malaysia. However, it is threatened with habitat loss and fragmentation by ongoing deforestation. Penang is a developed urban island, with primary and secondary forest patches that are inhabited by langurs. So far there has been no detaile...

Spatial and temporal use of oil palm plantations by wild Macaca nemestrina and its implication for mitigating human-wildlife conflicts." I have been investigating the visitation frequencies, activity patterns, feeding behaviour and rate of oil palm fruit consumption of a group of habituated pigtailed macaques (Macaca nemestrina). This group has b...

Background: Rattans are widespread throughout paleo-tropical forests; however, there is no information on their contribution to above-ground biomass (AGB). Aims: This study established biomass baseline values for 11 different rattan species in a Malaysian primary forest, and calculated the overall rattan AGB contribution and dynamics during two yea...

Despite their importance for the rain forest ecosystem, it is still not much known about the community composition of small frugivorous mammals in West-Malaysian forests. Therefore, we conducted a mark and recapture study in four 100 m x 100 m sized plots in a lowland Dipterocarp forest of Peninsular Malaysia for 4000 trap nights. Plots hosted eith...

Primates play an important role in the seed dispersal of a multitude of plant species, including rattans (Calamoideae). Here, camera-trapping was used as a means of identifying mammal rattan fruit predators of two non-climbing rattan species, Calamus castaneus Griff. and Daemonorops calicarpa (Griff.) Mart., at a lowland dipterocarp forest of West...

In order to study small frugivorous terrestrial mammals we conducted a mark and recapture program in five 1 ha-sized primary jungle plots in the Segari Melintang Forest Reserve, Perak (4° 18’N, 100° 34’ E) from November 2010 until December 2011. Plots were set both at the forest edge joining oil-palm plantations and deeper in the forest, and hosted...

Calamus castaneus (subfamily Calamoideae) is one of the most common rattan species in Peninsular Malaysia yet little is known about its reproductive behavior. Although C. castaneus is known to produce new shoots from its stem, here, we present evidence of the formation of a new shoot from the inflorescence apex. PALMS 56(1): 36–40 1. Acaulescent no...