Oil Palm Smallholdings Research Articles

The socio-economic and cultural impacts of the Pan Borneo Highway on Indigenous and local communities in Sabah, Malaysian Borneo.

Road and highway development can provide multiple benefits to society, but without careful planning, this development can result in negative social and environmental impacts. The 1,200 km Pan Borneo Highway project (PBH) in Sabah, Malaysian Borneo, is constructing new highways and up-grading 2-lane roads to 4-lane highways. We assessed the potential impact of the PBH on communities using three width scenarios of 50m, 75m and 100m for planned highway alignments, and identified potentially impacted dwellings and community lands. We estimated that 65–93 villages will be impacted, and that 1,712–7,093 dwellings and 3,420–6,695 ha of community lands (e.g. paddy, oil palm smallholdings and rubber) may be lost to the PBH. Due to land tenure technicalities, many affected households may not get compensation for the loss of their homes and lands. The PBH will disproportionally impact Sabah’s Indigenous Peoples, with the Kadazandusun most affected. For this study to be constructive, we provide a low impact alternative alignment for a part of the PBH; discuss the socio-economic and cultural impacts of the PBH, and offer some perspectives on current planning procedures in Sabah to support more sustainable and equitable development.

No evidence for trade‐offs between bird diversity, yield and water table depth on oil palm smallholdings: Implications for tropical peatland landscape restoration

Abstract Tropical peat swamp forests retain large carbon stocks and support unique biodiversity, but clearance and drainage for agriculture have resulted in fires, carbon emissions and biodiversity losses. Initiatives to re‐wet cultivated peatlands may benefit biodiversity if this protects remaining forests from fire and agricultural encroachment, but there are concerns that re‐wetting could reduce yields and damage livelihoods, as relationships between drainage, on‐farm biodiversity, and crop yields have not been studied. We examined oil palm fruit yields and bird diversity on 41 smallholder farms in Jambi (Sumatra, Indonesia), which varied in drainage intensity (12‐month mean water table per plot from August 2018 to August 2019: −52 to −3 cm below‐ground). We also compared farm bird diversity with a neighbouring area of protected peat swamp forest (11,000 ha, 21 plots; mean water table per plot −3 to +15 cm). Bird species richness (3–18 species per plot), species composition and oil palm yields (4.5–19.2 t fresh fruit bunch ha−1 year−1) varied among farms, but were not detectably affected by water table depth, although ground‐level vegetation was more complex on wetter farms. Bird richness in oil palm (mean = 10.3 species per plot) was <50% of that in forest (26 species per plot), and only 3 of 35 conservation‐priority species found in forest were recorded in oil palm. Synthesis and applications. Tropical peatlands in Indonesia have been drained to allow farmer access and improve farm yields, but we found no trade‐offs between drainage depth, yields and bird diversity on smallholder oil palm farms in our study landscape within the studied range of drainage depths. Current restoration initiatives to re‐wet peat may benefit farmers by reducing fire risk, without affecting yields. Wetter farms had increased understorey vegetation complexity, but this did not affect bird diversity, so we find no evidence that re‐wetting improves on‐farm biodiversity. However, on‐farm fire reduction efforts in cultivated peatlands, including re‐wetting, will be vital for reducing the risk of fires escaping into nearby forests, which contain unique and diverse bird species assemblages. Protection of remaining peatland forests from fire and clearance is key for biodiversity conservation, and for providing a source of seed dispersers and genetic material for future forest and landscape restoration efforts. Restoration of more biodiversity‐friendly land covers will improve landscape permeability and help conserve species and the ecosystem services they deliver.

Improving economic and environmental outcomes in oil palm smallholdings: The relationship between mulching, soil properties and yields

CONTEXTThe area under oil palm cultivation has expanded importantly in South-East Asia. The resulting land-use transformations are associated with environmental degradation such as substantial carbon dioxide emissions. Soil conservation practices can contribute to more sustainable oil palm systems by increasing soil organic carbon (SOC) contents and yields. One soil conservation practice in oil palm plantations is the mulching with empty fruit bunches (EFB). OBJECTIVEWe estimated the relationship between EFB mulching and, respectively, yields, SOC and total nitrogen contents, the carbon‑nitrogen ratio and the average bulk density in smallholder oil palm plantations. We further analyzed the determinants of smallholders' EFB application taking into account regional market, farm, and plot level aspects, as well as farmers' perceptions. METHODSWe estimated the relationship between mulching and yields with panel data, and between mulching and soil properties with cross-sectional data. We accounted for the possible selection bias of the decision to apply EFB mulching with instrumental variable estimations. Descriptive analysis was used to analyze the determinants of smallholder EFB use. RESULTS AND CONCLUSIONSOur results indicated that in particular the regional supply in EFB and farmers' wealth levels were correlated with smallholder EFB mulching. EFB mulching was associated with 39% higher yields and 19% higher SOC contents. We attribute the higher yields to potentially improved soil chemical functions linked to higher SOC contents, such cation exchange capacity effects, and to an increased K and potentially Mg availability. Since EFB is not available in sufficient quantity to be applied to all plantations, policy makers could identify user groups with the greatest potentials for environmental and income improvements. Site-specific life cycle assessments and yield effects can help to inform such identification. SIGNIFICANCEDespite their growing importance in the oil palm sector, evidence on the effect of EFB mulching was missing for smallholder farmers. Because of associated higher SOC contents and yields, our findings indicate that the promotion of EFB mulching as best management practice could potentially contribute to more sustainable oil palm systems. Strengthening inclusive value chains for smallholders, information provision and investments in road infrastructure represent potential policy instruments to increase smallholder EFB application. The identification and promotion of best management practices are important with view to the still ongoing oil palm expansion in South-East Asia, and progressively in other parts of the world.

Proximity to forest mediates trade‐offs between yields and biodiversity of birds in oil palm smallholdings

AbstractThere is much debate about how best to mitigate the effects of agricultural expansion on biodiversity, especially in the tropics. Recent studies have emphasized that proximity to natural habitats can enhance farmland biodiversity, yet few studies have examined whether or not such proximity mediates local trade‐offs between yields and biodiversity, and hence alters conclusions about the ecological benefits of alternative farming strategies. Here we examine yield‐biodiversity trade‐offs, focusing on birds in oil palm smallholdings at different distances from remaining areas of forest, including a large forest reserve, in Ghana. We found significantly fewer birds on higher‐yielding than lower‐yielding farms, in terms of both species richness and abundance. For forest specialist birds (likely to be highly vulnerable to conversion of land to agriculture) we also found a greater trade‐off (i.e., lower richness and abundance for a given yield) at farms further from forest, to the extent that increasing distance to the nearest forest from 1 to 10 km had a similar effect as a 3‐ to 5‐fold increase in fruit yield brought about by increased intensification. Our study highlights the importance of accounting for the effects of natural forest in the landscape when considering agricultural policies for biodiversity protection, underlining the importance of a landscape‐scale approach to conservation.

IMPROVING CITRONELLA OIL PROCESSING MARKET ACCESS FOR SMALL AND MEDIUM ENTERPRISES TO OVERCOME

Citronella oil production has been developed by the Regional Government of the South Tapanuli District through the Forest Management Unit (KPH), the Agriculture Office and the Industry Office. For KPH, this program serves to gradually replace oil palm smallholdings in forest areas. For the Agriculture and Industry Offices, this program is intended to increase farmer income, especially during the Covid19 Pandemic. However, businesses have faltered as citronella oil prices dropped dramatically. Many farmers cannot survive and temporarily close their business. This is mainly caused by the limited market access of farmers due to an inadequate business scale and production quality. To overcome such a condition, farmers need to have a strong smallholder institution with a sufficient economic scale, as well as good coordination among stakeholders. This activity was carried out for 3 months through online and offline meetings. Farmers were introduced to both export and local market accesses. However, to utilize these opportunities farmers need to have a strong and adequate farmer institution. Through the Forum Group Discussion, progressive farmers and processors were gathered with farmers from 3 other sub districts, as well as other stakeholders related to the improvement of market access. The results showed that farmers and other stakeholders agreed to jointly support the development of the citronella oil industry in South Tapanuli. The FGD ended with the commitment of farmers and all stakeholders to form a South Tapanuli Citronella Oil multi-stakeholders Forum to improve the ability to deal with market fluctuations in the future.

Analisis Evaluasi Kebun PlaAnalisis Evaluasi Kebun Plasma Yang Dikelola Oleh Kebun Inti Dan Dikelola Sendiri Oleh Peserta Plasma Terhadap Pendapatan Petani Kelapa Sawit (Kasus Pt. Pinago Utama, Kabupaten Musi Banyu Asin Provinsi Sumatera Selatan)

This study aims to determine and analyze the differences and the effect of production on the income of plasma palm oil farmers who are independently managed and managed in the core of PT. Pinago Utama. This research method uses a quantitative approach, the type of research is a survey. The sample was determined by 60 stratified random sampling methods. Data were analyzed using the independent sample mean difference test and simple linear regression. The results showed that there was an insignificant difference in the production of oil palm smallholdings managed by nucleus and those managed independently by farmers. However, there are significant differences in farmers' incomes, production costs and the cost of production of plasma oil palm estates managed by the nucleus and those managed by farmers independently. The cost of production of the nucleus estate managed by the nucleus is Rp. 576.65 / kg 39.17% lower than smallholdings which are managed independently by farmers (Rp. 947.95 / kg). Changes in production obtained by farmers have a significant effect on changes in income, both for estates managed by the nucleus and those managed independently by farmers. Thus there is a difference in the effect of production on farmers' income by almost 50% (49.88%)

The impacts of oil palm plantations on local and migrant smallholders’ incomes

In Indonesia, oil palm plantations have long affected income levels positively. Furthermore, Indonesia has developed oil palm smallholdings in 1980 to improve rural incomes. The success of this program has attracted other farmers and migrants to further developed oil palm plantations. Those who collaborated with companies were known as scheme smallholdings, while the others are known as independent smallholdings. In general, the lack of professional assistance has caused independent smallholdings to perform lower than the scheme ones. In addition, on average, the migrants also performed better as they were familiar with the collective actions of group activity management. Using as many as 210 and 219 scheme and independent smallholders from the Provinces of North Sumatra, South Sumatra, Jambi and Riau, such assumption were tested using the ANOVA compare means test of the four groups, namely schemed local and migrant, and independent local and migrant. Comparisons between the smallholders’ incomes and the Regional Minimum Wages of each province were analysed. The results showed that oil palm plantations have significantly improved the smallholders’ incomes in all provinces, although the impacts were observed to be higher for the scheme-migrant smallholders, not only concerning income, but also for productivity and selling price. However, this was likely due to the difference between scheme and independent rather than locals and migrants. This was partly explained due to the collective actions of all migrant-schemed smallholders in both the input purchases and the output sales and around 50% of the local-schemed, while almost all independents did it individually.

Can Forest-Associated Nocturnal Birds Persist in Oil Palm Agroecosystem?

A high demand for palm oil has led to the continued expansion of oil palm agriculture at the expense of tropical forests and forest biotic communities in many developing countries. The response of wildlife to oil palm establishment has been shown to vary according to taxa, and many forest species may not be able to adapt to the altered landscape. Many nocturnal bird species have been recorded in oil palm agriculture. Whether such forest species can also thrive in such a landscape is not known, and their responses to habitat complexity are poorly understood. We conducted point surveys of nocturnal birds (Tytonidae, Strigiformes and Caprimulgiformes over 80 points spaced at least 800 m apart and revisited five times) in oil palm smallholdings at Tanjung Karang, Kuala Selangor. Environmental factors measured at each point included: average height of oil palm stands, palm density, crop richness, and distances to the nearest forest, river and road. We recorded a total of 577 individuals of seven species. Palm density and distance to river were found to positively influence nocturnal bird species richness, whereas distance to the nearest forest was found to negatively influence avian species richness. In the case of abundance, number of oil palms, crop richness, and distance to the nearest river were found to influence nocturnal bird abundance positively in the smallholdings; however, distance to the nearest forest was found to influence bird abundance negatively. These findings suggest that maintaining key vegetation structure while reducing manmade structures such as roads may benefit nocturnal bird species in the smallholdings particularly those of open and semi-open habitats. However, the number of forest-associated species remained low in the smallholdings, which may only serve as suboptimal habitat for these birds. This implies that forest-associated species may not be able to persist in such landscapes.

Birds associated with different tree species and structures in oil palm agroforestry landscapes in Malaysia

ABSTRACTThe expansion of oil palm (Elaeis guineensis) cultivation has been recognised as a major threat to tropical biodiversity. Smallholdings, however, unlike large-scale conventional monoculture oil palm plantations, often practice polyculture which may resemble an agroforestry system. These private holdings provide more heterogeneous vegetation which may support greater a greater diversity of birds. This study compared species richness and abundance of birds detected perching in oil palm (both dead and living trees) and seven other planted crop species within oil palm smallholdings. Using transect line surveys, we recorded a total of 816 birds of 39 species from 20 families. Our results indicate that bird species richness and abundance differed significantly between oil palm and the other planted tree species. Non-oil palm trees cumulatively increased bird species richness and abundance. Although birds overall perched more frequently on living oil palm trees (probably reflecting relative abundance), other species including breadfruit, mango, papaya, banana, and coconut, as well as dead trees, were also used. By measuring effect size, we also found that both bird species richness and abundance rely on tree structure and type of tree species. These findings tentatively suggest that providing a larger diversity of tree species within intensively managed oil palm plantations may support a wider variety of local bird species compared to monocultures.

Risk Analysis for Sustainability of Oil Palm Smallholdings

Oil palm plantation is well known as a profitable business. In general, oil palm smallholders have a higher income than farmers of other commodities. However, most smallholdings have land sizes that do not reach the economic scale. Together with the lack of managerial skills, smallholdings are likely to be more vulnerable to production and price fluctuations, which in turn affects their business sustainability. This study was conducted to analyze the possibility and impact of production and price changes to the oil palm smallholdings’ sustainability. Data were collected from 240 schemed and independent smallholders in Asahan, Labuhan Batu, Labuhan Batu Utara and Labuhan Batu Selatan, which were selected with purposive cluster sampling. The production and market risk possibility and impact were measured with Value at Risk Method. The estimations showed that smallholders had a low risk possibility and impact, which partly stemmed from the enormously low threshold of both production and market risks. In fact, on average, smallholders’ productivity is less than 20% of the potentials, and many schemed smallholders receive low prices due to their aged trees. This may be harmful to smallholding sustainability. Since VaR only considers risks from variations of production and price, a low threshold is not considered as a risk for sustainability. Therefore, further studies using different thresholds or approaches are required. From the policy implication point of view, to address such a situation, the Indonesian government needs to improve smallholdings’ productivity and their composition of trees.

The effect of oil palm agricultural expansion on group size of long-tailed macaques (Macaca fascicularis) in Peninsular Malaysia

Large-scale expansion of oil palm (Elaeis guineensis) monocultures across Southeast Asia are creating ecosystems with homogenous habitats with low species diversity. However, heterogeneity varies between oil palm smallholdings and large-scale plantations, with greater habitat heterogeneity found on smallholdings. To date, there has been a paucity of field research on primate species, particularly macaques in oil palm plantations. In this study, we investigate the group size of long-tailed macaques (Macaca fascicularis) in four habitat types: unlogged forest, logged forest, large-scale oil palm plantations, and smallholdings. Field censuses were conducted in 2015 and 2016 to determine the group size of M. fascicularis in large-scale oil palm plantations and oil palm smallholdings. These data from oil palm plantations were compared to surveys conducted on a logged lowland forest reserve and a previous study in an unlogged lowland forest. We found that group size of M. fascicularis in large-scale plantations was lower compared to smallholdings, logged forest and unlogged forest. The chi-square test showed that the age class (juvenile or adult) of M. fascicularis was associated with farming systems. The paper concludes that the expansion of large-scale oil palm monocultures should be limited because of its adverse impacts on biodiversity including common species such as M. fascicularis.

Territorial and Duet Calls of Three Malaysian Owl Species

Vocalisations of tropical birds are still largely unexplored particularly the nocturnal species. This study examined and quantitatively described the territorial calls and duets of the Sunda Scops-Owl (Otus lempiji), Brown Boobook (Ninox scutulata) and Spotted Wood-Owl (Strix seloputo) based on 105 territorial call and four duetting recordings collected from one forest reserve and oil palm smallholdings in Selangor, Peninsular Malaysia. Wilcoxon signed-rank tests found significant differences (p<0.05) for almost all vocal parameters measured from the spectrograms derived from the duets with one higher-pitched than the other. Being the first study to describe the vocal structure of the duetting calls of the three Malaysian strigids, this study serves as a baseline for future behavioural study of nocturnal birds particularly pertaining to conspecific interactions in the Sunda region.

Smallholders’ willingness to pay for dura marking oil palm seeds

In 2018, around 4 million ha of oil palm smallholdings need to be replanted. Indonesia could utilize this moment to improve smallholdings’ productivity by ensuring the usage of good quality seeds. For the industry, Dura is considered as bad seeds as its thick shells can damage the machine and the oil content is low. Therefore, most mills do not want to buy it, hence the selling price is low. In fact, most smallholdings’ use uncertified seedlings that include many contaminated Dura. Unfortunately, smallholders can only detect this 3 years after the planting and spending a considerable amount of production costs. Actually, to avoid the unnecessary loss a Dura marking technique can be applied to the oil palm seeds. However, most smallholders are unlikely consider Dura usage as an important issue due to the higher weight and higher sales revenue. This study is conducted to analyse smallholders’ willingness to pay (WTP) for seed marking service. Data is collected from 60 independent smallholders in Labuhan Batu Utara, which mostly use the uncertified seedlings. The willingness to pay is measured with Conjectural Variations Approach, revealing 71% of the respondents are willing to pay the Dura seed marking service, although still with a minimum level of WTP. Pearson Chi Square Correlation Test shows that the WTP for Dura Marking Service is only significantly correlated with the smallholders’ knowledge and perception, but not with their land size and experience. Based on the results, a number of policy implication are included.

THE TRANSFORMATION OF THE MONOCULTURE SYSTEM TOWARDS SUSTAINABLE FARMING PRACTICES AMONG MALAY SMALLHOLDINGS IN KLUANG, JOHOR

Malaysia is known as the largest exporter and second largest producer of world palm oil market. Despite such contributions, a huge amount of forest land has been supplanted by oil palm cultivation. This activity is considered as a major driver of deforestation, which contributes to three-quarters of tropical deforestation globally. Critiques suggest agroforestry systems as option to overcome the issues brought up by the monoculture system of oil palm cultivation. This study is directed to study plant composition and arrangement for agroforestry systems in oil palm smallholdings. Data were gathered using a qualitative approach involving 10 biggest oil palm Malay smallholdings at Kluang, Johor. The study reveals that arrangement involves triangular, double avenue, and boundary planting systems. Further analysis traced that these plant species and arrangement can be categorized into two main categories which are: (i) sustainable plant composition and arrangement, and (ii) unsustainable into sustainable plant composition and arrangement. The study concluded that the transformation of the monoculture system with low sustainability towards more sustainable farming practices of agroforestry systems can actually be achieved through five considerations identified as (i) crop component (ii) maturity of oil palm (iii) market values and demand (iv) belowground and aboveground interaction, and (v) diversification of plant composition and arrangement.

THE TRANSFORMATION OF THE MONOCULTURE SYSTEM TOWARDS SUSTAINABLE FARMING PRACTICES AMONG MALAY SMALLHOLDINGS IN KLUANG, JOHOR

Malaysia is known as the largest exporter and second largest producer of world palm oil market. Despite such contributions, a huge amount of forest land has been supplanted by oil palm cultivation. This activity is considered as a major driver of deforestation, which contributes to three-quarters of tropical deforestation globally. Critiques suggest agroforestry systems as option to overcome the issues brought up by the monoculture system of oil palm cultivation. This study is directed to study plant composition and arrangement for agroforestry systems in oil palm smallholdings. Data were gathered using a qualitative approach involving 10 biggest oil palm Malay smallholdings at Kluang, Johor. The study reveals that arrangement involves triangular, double avenue, and boundary planting systems. Further analysis traced that these plant species and arrangement can be categorized into two main categories which are: (i) sustainable plant composition and arrangement, and (ii) unsustainable into sustainable plant composition and arrangement. The study concluded that the transformation of the monoculture system with low sustainability towards more sustainable farming practices of agroforestry systems can actually be achieved through five considerations identified as (i) crop component (ii) maturity of oil palm (iii) market values and demand (iv) belowground and aboveground interaction, and (v) diversification of plant composition and arrangement.

INTRODUCTION TO SPECIAL ISSUE 4 : 2017

This issue of Planning Malaysia Journal includes a mixture of articles addressing various issues in contemporary urban planning. Article 1 raises the question of whether green initiatives in educational institutions, especially universities, were successful in producing green graduates. A survey among green and non-green universities students showed that there is no significant difference in the level of perception, attitude and responsible environmental behaviour between green and non-green universities graduates. Thus, it suggests that students’ involvement in universities’ green initiatives should be increased.Article 2 discusses the impacts of street urban design on the perceived safety by women respondents. As women’s role in the cities becoming more pronounced, the authors suggest that streets and urban design should consider the safety of women so that street can become a safe and highly utilised public space. Article 3 looks at the factors affecting house prices in Malaysia in order to determine the alternative benchmark for Islamic home financing scheme. It shows that house price index are influenced by economic growth, demand for housing loan and construction materials. Article 4, in the meantime, compares the Islamic home financing schemes on offer in Malaysia nowadays, and suggest that there is a need for banks to move on from the Al-Bay Bithaman Ajil to Musharakah Mutanaqisah Partnership housing financing scheme.Article 5 looks how innovative management of natural resources leads to increased participation of the local community and improved revenue for rural businesses. These, in turn, motivates local stakeholders to continue preserving the resources. Article 6 examines the practices regarding food waste management in hotels in Langkawi. It found that there was a lack of emphasis from the hotels on their policy related to wastage of food and unsustainable food consumption pattern by their guests. This reflects on the lack of practices towards sustainable food waste management by the hotel sector.Article 7 identifies changes and threats to Malay landscape preservation in traditional Malays houses in Melaka and Kelantan. It concludes that threats to such preservation include inappropriate use of garden space, problems regarding house ownership, inadequate fund for maintenance, and current development trend that leads to traditional Malay garden setting being replaced by modern setting.Article 8 discusses the use of agroforestry approach to improve sustainability of oil palm smallholdings. Rapid development and expansion of natural forest into oil palm land has decreased the agricultural sustainability of Malaysian oil palm production. However, the article shows that sustainability of oil palm smallholdings can be improved through agroforestry, which at the same time was found to also improve income of the smallholders.

INTRODUCTION TO SPECIAL ISSUE 4 : PLANNING MALAYSIA JOURNAL

This issue of Planning Malaysia Journal includes a mixture of articles addressing various issues in contemporary urban planning. Article 1 raises the question of whether green initiatives in educational institutions, especially universities, were successful in producing green graduates. A survey among green and non-green universities students showed that there is no significant difference in the level of perception, attitude and responsible environmental behaviour between green and non-green universities graduates. Thus, it suggests that students’ involvement in universities’ green initiatives should be increased.Article 2 discusses the impacts of street urban design on the perceived safety by women respondents. As women’s role in the cities becoming more pronounced, the authors suggest that streets and urban design should consider the safety of women so that street can become a safe and highly utilised public space. Article 3 looks at the factors affecting house prices in Malaysia in order to determine the alternative benchmark for Islamic home financing scheme. It shows that house price index are influenced by economic growth, demand for housing loan and construction materials. Article 4, in the meantime, compares the Islamic home financing schemes on offer in Malaysia nowadays, and suggest that there is a need for banks to move on from the Al-Bay Bithaman Ajil to Musharakah Mutanaqisah Partnership housing financing scheme.Article 5 looks how innovative management of natural resources leads to increased participation of the local community and improved revenue for rural businesses. These, in turn, motivates local stakeholders to continue preserving the resources. Article 6 examines the practices regarding food waste management in hotels in Langkawi. It found that there was a lack of emphasis from the hotels on their policy related to wastage of food and unsustainable food consumption pattern by their guests. This reflects on the lack of practices towards sustainable food waste management by the hotel sector.Article 7 identifies changes and threats to Malay landscape preservation in traditional Malays houses in Melaka and Kelantan. It concludes that threats to such preservation include inappropriate use of garden space, problems regarding house ownership, inadequate fund for maintenance, and current development trend that leads to traditional Malay garden setting being replaced by modern setting.Article 8 discusses the use of agroforestry approach to improve sustainability of oil palm smallholdings. Rapid development and expansion of natural forest into oil palm land has decreased the agricultural sustainability of Malaysian oil palm production. However, the article shows that sustainability of oil palm smallholdings can be improved through agroforestry, which at the same time was found to also improve income of the smallholders.

Vocal individuality of large-tailed nightjar (Caprimulgus macrurus) in Peninsular Malaysia

All four nightjar species resident in Peninsular Malaysia are vocally distinct, yet they remain little studied. Conventional field methods based on visual cues to study diurnal species may be impractical for nightjars. Alternatively, aural survey can potentially be applied on nightjars provided that individuality in their vocalisations can be proven. Our study aimed to determine the vocal individuality of the common, large-tailed nightjar (Caprimulgus macrurus) in oil palm smallholdings and an isolated forest patch located in Selangor, Peninsular Malaysia. From the call recordings obtained from 22 individuals, results of the Kruskal-Wallis analysis revealed significant differences in all the nine vocal parameters (call length, interquartile range bandwidth, low, high, average, centre and peak frequencies as well as first and third quartile frequencies) measured among individual nightjars (p < 0.001) regardless of study sites. Discriminant Function Analysis showed that more than 94.5% of original grouped cases were correctly classified. This implied that the majority of vocalizations can be assigned to individual birds based on the parameters measured. This study demonstrated the occurrence of vocal individuality in the large-tailed nightjar and such a finding pertaining to distinct vocalisations at the individual level will compensate for the limited access to visual cues in field surveys, as with the case for all nocturnal birds.

Vocal Individuality of Sunda Scops-Owl (Otus lempiji) in Peninsular Malaysia

Like many owl species, Sunda Scops-Owls (Otus lempiji) are difficult to monitor using traditional survey techniques, because of their nocturnal habits, secretive nature, and cryptic coloration. Individual variation in vocalizations could potentially be used to distinguish individuals of this owl species, as has been demonstrated for many bird species. The objectives of this study were to describe the territorial call of Sunda Scops-Owls, to determine whether the calls can be distinguished individually, and to examine whether the calls from the same individuals were stable over time. We analyzed 75 recordings collected from 12 owls from December 2014 to June 2015 in a lowland forest and oil palm smallholdings in Selangor State, Peninsular Malaysia. Using two temporal parameters and six frequency parameters derived from spectrogram, we employed ANOVA tests and found significant differences for all parameters among individual owls. Discriminant function analysis correctly classified 97.1% of the owl calls to the correct individuals. Based on the Wilcoxon signed-rank test, all vocal parameters did not vary significantly for the six birds that were vocally active over two predetermined survey sessions within the breeding period. Our results demonstrated that Sunda Scops-Owls can be identified individually by their vocalizations. This implies that assessing vocal individuality can be useful as a noninvasive method for surveying the Sunda Scops-Owls and the method should be further tested for other little-known owl species in the tropics.

Nocturnal bird composition in relation to habitat heterogeneity in small scale oil palm agriculture in Malaysia

The expansion of oil palm cultivation is recognised as a major cause of tropical biodiversity loss. In contrast to large-scale plantations, oil palm smallholdings being more heterogeneous may support greater biodiversity. This study examined the effects of local and landscape level variables on the composition of nocturnal bird species in Malaysian oil palm smallholdings. Using visual and aural point sampling, we made 1408 encounters with nine owl and two nightjar species. The Biota-Environment-Stepwise matching analyses (BEST) indicated four predictor variables (three local variables; number of crop species, widths of roads and trenches, and one landscape variable; distance to the nearest main road) significantly influenced the community assemblages of nocturnal bird species in the smallholdings. Generalized Linear Models (GLMs) further indicated seven predictor variables (numbers of palms and houses, widths of roads and trenches, distances to the nearest forest and house, as well as palm height) significantly influenced the abundances of certain nocturnal species. These findings not only improve our understanding on habitat preference of nocturnal birds in the Sunda region but also support the argument that habitat complexity in cultivated areas may aid in biodiversity conservation, at least for nocturnal birds.