Since 1988 until now I have been a lecturer at the Biology Faculty, Universitas Nasional. I am also active in field biology activities, such as: biodiversity conservation
Understanding of animal responses to dynamic resource landscapes is based largely on research on ... more Understanding of animal responses to dynamic resource landscapes is based largely on research on temperate species with small body sizes and fast life histories. We studied a large, tropical mammal with an extremely slow life history, the Western Bornean orangutan (Pongo pygmaeus wurmbii), across a heterogeneous natural landscape encompassing seven distinct forest types. Our goals were to characterize fluctuations in abundance, test hypotheses regarding the relationship between dispersion dynamics and resource availability, and evaluate how movement patterns are influenced by abiotic conditions. We surveyed abundance in Gunung Palung National Park, West Kalimantan, Indonesia, for 99 consecutive months and simultaneously recorded weather data and assessed fruit availability. We developed a Bayesian hierarchical distance sampling model to estimate population dispersion and assess the roles of fruit availability, rainfall, and temperature in driving movement patterns across this heterogeneous landscape. Orangutan abundance varied dramatically over space and time. Each forest type was important in sustaining more than 40% of the total orangutans on site during at least one month, as animals moved to track asynchronies in fruiting phenology. We conclude that landscape-level movements buffer orangutans against fruit scarcity, peat swamps are crucial fallback habitats, and orangutans' use of high elevation forests is strongly dependent on abiotic conditions. Our results show that orangutans can periodically occupy putative-sink habitats and be virtually absent for extended periods from habitats that are vitally important in sustaining their population, highlighting the need for long-term studies and potential risks in interpreting occurrence or abundance measures as indicators of habitat importance.
Soybean is the third most important food commodity in Indonesia, which is a cheap source of prote... more Soybean is the third most important food commodity in Indonesia, which is a cheap source of protein and rich in different nutritional contents for humans. This study aimed to analyze the four genotypes of the crossing parents using SSR primers and select one SSR polymorphic primer to confirm the F1 generation alleles compared to their parents. The research was conducted in the laboratory and greenhouse of the Indonesian Center for Agricultural Biotechnology and Genetic Resources Research and Development (ICABIOGRAD). The research activities included a polymorphic primers survey, population formation, and confirmation of crossing populations using one polymorphic primer. A total of 20 SSR primers were used to amplify the DNA of the four crossing parents (Biosoy 1, Biosoy 2, Demas, and Tanggamus). The results of the polymorphic SSR survey showed that 6 SSR primers could distinguish the combination of Biosoy 2 vs Demas parents, then 7 SSR primers could distinguish the combination of Bi...
The communicative function of primates' self-directed behaviours like scratching has gained i... more The communicative function of primates' self-directed behaviours like scratching has gained increasing attention in recent years, but their intentional use is still debated. Here, we addressed this issue by exploring the communicative function of 'loud scratches' in wild Sumatran orangutans. Building on previous studies in chimpanzees, we examined the prediction that audio-visual loud scratches are used communicatively in mother–infant travel coordination. Specifically, we examined whether individual, social and scratch features affected the use of pre-move scratches, markers of intentional signal use and approach responses. We analysed a total of 1457 scratching bouts, produced by 17 individuals (including four mothers and their dependent offspring) observed during 305 h of focal follows. Overall, we found that scratching bouts preceded departure mainly when these were produced by mothers and showed features of exaggeration. If the scratching individual was a mother, as...
The communicative function of primates' self-directed behaviours like scratching has gained i... more The communicative function of primates' self-directed behaviours like scratching has gained increasing attention in recent years, but their intentional use is still debated. Here, we addressed this issue by exploring the communicative function of 'loud scratches' in wild Sumatran orangutans. Building on previous studies in chimpanzees, we examined the prediction that audio-visual loud scratches are used communicatively in mother–infant travel coordination. Specifically, we examined whether individual, social and scratch features affected the use of pre-move scratches, markers of intentional signal use and approach responses. We analysed a total of 1457 scratching bouts, produced by 17 individuals (including four mothers and their dependent offspring) observed during 305 h of focal follows. Overall, we found that scratching bouts preceded departure mainly when these were produced by mothers and showed features of exaggeration. If the scratching individual was a mother, associates were more likely to be visually attentive during pre-move scratches than in other contexts. Approach or follow responses to scratches by individuals in association were predicted by context, the relationship with the scratcher (i.e. offspring) and the associate's attentional state. We conclude that orangutan mothers use loud scratches as communicative strategies to coordinate joint travel with their infants.
At the Population and Habitat Viability Analysis (PHVA) Workshop for orangutans, estimates of hab... more At the Population and Habitat Viability Analysis (PHVA) Workshop for orangutans, estimates of habitat and population numbers for Sumatran orangutans (Pongo pygmaeus abelii) were derived from field biologists who studied, or are presently studying, orangutans at Ketambe in Gunung Leuser National Park. For Sumatra, the exact boundaries of orangutan distribution are not known, but there are several distinct populations, including the lesser-known Singkil population and the Sembabala-Dolok Sembelin population. The Greater Leuser orangutan population, which extends beyond the national park boundaries, is thought to cover approximately 11,710 km2 and has two distinct populations. Using a correction or “safety” factor to derive population estimates, the western population is thought to number 5,700 individuals, and is the most important orangutan population in Sumatra; the eastern population is thought to number 3,500 individuals. Within the restricted boundaries of Gunung Leuser National Park, the area covered by the western population is 5,570 km2 and the corrected population size is about 3,450 individuals; the area covered by the eastern population is 2,957 km2 and the corrected population size is about 2,400 individuals. The total number of orangutans in the park probably is about 5,850 individuals. The Greater Leuser populations were judged to be among the strongest in Southeast Asia, in terms of numbers and potential for protection. Gunung Leuser National Park was considered to be the most vital habitat to the long-term survival of the Sumatran orangutan.
Flanged male orang-utans emit loud vocalizations called long calls. In this study, we examined th... more Flanged male orang-utans emit loud vocalizations called long calls. In this study, we examined the correlates of variation in long-calling rates among flanged male Sumatran orang-utans, as well as the ranging responses of adult females and flanged males to these long calls. Males that gave calls more often were more likely to approach calls by others. Results bolster a female attraction function of long calls. Flanged males did not significantly avoid or approach long calls. However, males called more when alone than when guarding a female mate, and adult females significantly approached long calls, especially those of the dominant male, and did so regardless of their reproductive state, allowing them to remain within earshot of calling males. The possible selective advantages of this response include avoidance of harassment and infanticide by males. These findings confirm the existence of some form of social organization above the mother-infant unit.
Vertebrate predation and consumption by wild Bornean orangutans ( Pongo pygmaeus spp.) is rare. I... more Vertebrate predation and consumption by wild Bornean orangutans ( Pongo pygmaeus spp.) is rare. In contrast to recorded observations of slow loris consumption by Sumatran orangutans ( Pongo abelii ), no cases of this have been previously published for Bornean orangutans in the wild. In 2017, we observed the capture and consumption of a slow loris ( Nycticebus borneanus ) by an adult unflanged male Bornean orangutan at Tuanan Orangutan Research Station, which is located in the Kapuas region of Central Kalimantan. The unflanged male was together with an adult female and her 3.5-year-old offspring throughout the event. However, despite the mother and her offspring watching the male closely and occasionally begging while he consumed the loris, he resisted all food-taking attempts. This study reports, to the best of our knowledge, the first documented case of slow loris predation and consumption by a Bornean orangutan, and thus provides an important data point for understanding primate predation on other primate species.
Indonesia, walaupun sebagai negara yang kaya akan keragaman hayati, namun dewasa ini mengalami be... more Indonesia, walaupun sebagai negara yang kaya akan keragaman hayati, namun dewasa ini mengalami berbagai tekanan terhadap keanekaragaman ini.Tekanan-tekanan ini bersumber dari dua masalah utama yaitu pertama, pembangunan yang tanpa memperhatikan keseimbangan alam sehingga telah menimbulkan perubahan yang merusak, dan kedua, meningkatnya populasi (penduduk).Perlu langkah-langkah untuk melestarikan alam dan fungsinya di Indonesia, secara serentak dan lintas sektoral {total football),demi meningkatkan daya dukung alam itu sendiri.Oleh karena itu, pelestarian alam ini harus menjadi pola perilaku hidup.Untuk membentuk pola perilaku ini perlu dilaksanakan 2 program utama yaitu a) pendidikan pelestarian alam dan lingkungan dan b) pendidikan etika dan moral.Pendidikan konservasi dan lingkungan selain sebagai langkah awal dalam strategi pelestarian alam, juga dipandang sebagai salah satu media untuk desiminasi hasil riset dan pengembangan dalam bidang keanekagaraman hayati.Aspek diseminasi di...
The economic empowerment model with industrialization approach is aimed at achieving, namely: Pro... more The economic empowerment model with industrialization approach is aimed at achieving, namely: Providing economic value added to banana grower farmers, increasing productivity is achieved by improving banana tree cultivation techniques that have superior quality, improving product quality through handling factors that cause banana quality degradation (viruses / pests / diseases banana stem rot, Use of post-harvest technology with an industrialization approach so that banana plant waste has good quality and raises economic added value from the waste with the support of various parties / industries and can reduce environmental pollution. In the second year research conducted a comparative study on handicrafts from banana stem waste craftsmen in Bojonegoro and Gresik Regencies and a socialization will be held on banana plant farmers in Nangroe Aceh Darussalam, so that it can increase the income of banana planters and can help the government create jobs. The research method used is actio...
Understanding of animal responses to dynamic resource landscapes is based largely on research on ... more Understanding of animal responses to dynamic resource landscapes is based largely on research on temperate species with small body sizes and fast life histories. We studied a large, tropical mammal with an extremely slow life history, the Western Bornean orangutan (Pongo pygmaeus wurmbii), across a heterogeneous natural landscape encompassing seven distinct forest types. Our goals were to characterize fluctuations in abundance, test hypotheses regarding the relationship between dispersion dynamics and resource availability, and evaluate how movement patterns are influenced by abiotic conditions. We surveyed abundance in Gunung Palung National Park, West Kalimantan, Indonesia, for 99 consecutive months and simultaneously recorded weather data and assessed fruit availability. We developed a Bayesian hierarchical distance sampling model to estimate population dispersion and assess the roles of fruit availability, rainfall, and temperature in driving movement patterns across this heterogeneous landscape. Orangutan abundance varied dramatically over space and time. Each forest type was important in sustaining more than 40% of the total orangutans on site during at least one month, as animals moved to track asynchronies in fruiting phenology. We conclude that landscape-level movements buffer orangutans against fruit scarcity, peat swamps are crucial fallback habitats, and orangutans' use of high elevation forests is strongly dependent on abiotic conditions. Our results show that orangutans can periodically occupy putative-sink habitats and be virtually absent for extended periods from habitats that are vitally important in sustaining their population, highlighting the need for long-term studies and potential risks in interpreting occurrence or abundance measures as indicators of habitat importance.
Soybean is the third most important food commodity in Indonesia, which is a cheap source of prote... more Soybean is the third most important food commodity in Indonesia, which is a cheap source of protein and rich in different nutritional contents for humans. This study aimed to analyze the four genotypes of the crossing parents using SSR primers and select one SSR polymorphic primer to confirm the F1 generation alleles compared to their parents. The research was conducted in the laboratory and greenhouse of the Indonesian Center for Agricultural Biotechnology and Genetic Resources Research and Development (ICABIOGRAD). The research activities included a polymorphic primers survey, population formation, and confirmation of crossing populations using one polymorphic primer. A total of 20 SSR primers were used to amplify the DNA of the four crossing parents (Biosoy 1, Biosoy 2, Demas, and Tanggamus). The results of the polymorphic SSR survey showed that 6 SSR primers could distinguish the combination of Biosoy 2 vs Demas parents, then 7 SSR primers could distinguish the combination of Bi...
The communicative function of primates' self-directed behaviours like scratching has gained i... more The communicative function of primates' self-directed behaviours like scratching has gained increasing attention in recent years, but their intentional use is still debated. Here, we addressed this issue by exploring the communicative function of 'loud scratches' in wild Sumatran orangutans. Building on previous studies in chimpanzees, we examined the prediction that audio-visual loud scratches are used communicatively in mother–infant travel coordination. Specifically, we examined whether individual, social and scratch features affected the use of pre-move scratches, markers of intentional signal use and approach responses. We analysed a total of 1457 scratching bouts, produced by 17 individuals (including four mothers and their dependent offspring) observed during 305 h of focal follows. Overall, we found that scratching bouts preceded departure mainly when these were produced by mothers and showed features of exaggeration. If the scratching individual was a mother, as...
The communicative function of primates' self-directed behaviours like scratching has gained i... more The communicative function of primates' self-directed behaviours like scratching has gained increasing attention in recent years, but their intentional use is still debated. Here, we addressed this issue by exploring the communicative function of 'loud scratches' in wild Sumatran orangutans. Building on previous studies in chimpanzees, we examined the prediction that audio-visual loud scratches are used communicatively in mother–infant travel coordination. Specifically, we examined whether individual, social and scratch features affected the use of pre-move scratches, markers of intentional signal use and approach responses. We analysed a total of 1457 scratching bouts, produced by 17 individuals (including four mothers and their dependent offspring) observed during 305 h of focal follows. Overall, we found that scratching bouts preceded departure mainly when these were produced by mothers and showed features of exaggeration. If the scratching individual was a mother, associates were more likely to be visually attentive during pre-move scratches than in other contexts. Approach or follow responses to scratches by individuals in association were predicted by context, the relationship with the scratcher (i.e. offspring) and the associate's attentional state. We conclude that orangutan mothers use loud scratches as communicative strategies to coordinate joint travel with their infants.
At the Population and Habitat Viability Analysis (PHVA) Workshop for orangutans, estimates of hab... more At the Population and Habitat Viability Analysis (PHVA) Workshop for orangutans, estimates of habitat and population numbers for Sumatran orangutans (Pongo pygmaeus abelii) were derived from field biologists who studied, or are presently studying, orangutans at Ketambe in Gunung Leuser National Park. For Sumatra, the exact boundaries of orangutan distribution are not known, but there are several distinct populations, including the lesser-known Singkil population and the Sembabala-Dolok Sembelin population. The Greater Leuser orangutan population, which extends beyond the national park boundaries, is thought to cover approximately 11,710 km2 and has two distinct populations. Using a correction or “safety” factor to derive population estimates, the western population is thought to number 5,700 individuals, and is the most important orangutan population in Sumatra; the eastern population is thought to number 3,500 individuals. Within the restricted boundaries of Gunung Leuser National Park, the area covered by the western population is 5,570 km2 and the corrected population size is about 3,450 individuals; the area covered by the eastern population is 2,957 km2 and the corrected population size is about 2,400 individuals. The total number of orangutans in the park probably is about 5,850 individuals. The Greater Leuser populations were judged to be among the strongest in Southeast Asia, in terms of numbers and potential for protection. Gunung Leuser National Park was considered to be the most vital habitat to the long-term survival of the Sumatran orangutan.
Flanged male orang-utans emit loud vocalizations called long calls. In this study, we examined th... more Flanged male orang-utans emit loud vocalizations called long calls. In this study, we examined the correlates of variation in long-calling rates among flanged male Sumatran orang-utans, as well as the ranging responses of adult females and flanged males to these long calls. Males that gave calls more often were more likely to approach calls by others. Results bolster a female attraction function of long calls. Flanged males did not significantly avoid or approach long calls. However, males called more when alone than when guarding a female mate, and adult females significantly approached long calls, especially those of the dominant male, and did so regardless of their reproductive state, allowing them to remain within earshot of calling males. The possible selective advantages of this response include avoidance of harassment and infanticide by males. These findings confirm the existence of some form of social organization above the mother-infant unit.
Vertebrate predation and consumption by wild Bornean orangutans ( Pongo pygmaeus spp.) is rare. I... more Vertebrate predation and consumption by wild Bornean orangutans ( Pongo pygmaeus spp.) is rare. In contrast to recorded observations of slow loris consumption by Sumatran orangutans ( Pongo abelii ), no cases of this have been previously published for Bornean orangutans in the wild. In 2017, we observed the capture and consumption of a slow loris ( Nycticebus borneanus ) by an adult unflanged male Bornean orangutan at Tuanan Orangutan Research Station, which is located in the Kapuas region of Central Kalimantan. The unflanged male was together with an adult female and her 3.5-year-old offspring throughout the event. However, despite the mother and her offspring watching the male closely and occasionally begging while he consumed the loris, he resisted all food-taking attempts. This study reports, to the best of our knowledge, the first documented case of slow loris predation and consumption by a Bornean orangutan, and thus provides an important data point for understanding primate predation on other primate species.
Indonesia, walaupun sebagai negara yang kaya akan keragaman hayati, namun dewasa ini mengalami be... more Indonesia, walaupun sebagai negara yang kaya akan keragaman hayati, namun dewasa ini mengalami berbagai tekanan terhadap keanekaragaman ini.Tekanan-tekanan ini bersumber dari dua masalah utama yaitu pertama, pembangunan yang tanpa memperhatikan keseimbangan alam sehingga telah menimbulkan perubahan yang merusak, dan kedua, meningkatnya populasi (penduduk).Perlu langkah-langkah untuk melestarikan alam dan fungsinya di Indonesia, secara serentak dan lintas sektoral {total football),demi meningkatkan daya dukung alam itu sendiri.Oleh karena itu, pelestarian alam ini harus menjadi pola perilaku hidup.Untuk membentuk pola perilaku ini perlu dilaksanakan 2 program utama yaitu a) pendidikan pelestarian alam dan lingkungan dan b) pendidikan etika dan moral.Pendidikan konservasi dan lingkungan selain sebagai langkah awal dalam strategi pelestarian alam, juga dipandang sebagai salah satu media untuk desiminasi hasil riset dan pengembangan dalam bidang keanekagaraman hayati.Aspek diseminasi di...
The economic empowerment model with industrialization approach is aimed at achieving, namely: Pro... more The economic empowerment model with industrialization approach is aimed at achieving, namely: Providing economic value added to banana grower farmers, increasing productivity is achieved by improving banana tree cultivation techniques that have superior quality, improving product quality through handling factors that cause banana quality degradation (viruses / pests / diseases banana stem rot, Use of post-harvest technology with an industrialization approach so that banana plant waste has good quality and raises economic added value from the waste with the support of various parties / industries and can reduce environmental pollution. In the second year research conducted a comparative study on handicrafts from banana stem waste craftsmen in Bojonegoro and Gresik Regencies and a socialization will be held on banana plant farmers in Nangroe Aceh Darussalam, so that it can increase the income of banana planters and can help the government create jobs. The research method used is actio...
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