Jantungspermum gunnellii: A giant Australian Legume from the Eocene of South Kalimantan, Borneo.

The forests of Southeast Asia form one of the world's greatest biodiversity hotspots, having a far higher species-to-area ratio than the tropical forests of Africa or the Americas. Surprisingly, unlike these areas, biodiversity in Southeast Asia does not have deep roots going back to the earliest Cainozoic, but rather has been assembled over this period, as new diversity was added by first the collision of India with Eurasia and then that of Sahul (the continental plate underlying Australia and New Guinea) with Sunda (the plate underlying Southeast Asia).

Theoretically, if organisms were able to spread from Sahul to Sunda as the two blocks collided, then the same should be true in reverse; organisms should also have spread from Sunda to Sahul. There is, however, little evidence for this at the current time. This disparity between the two regions may be due to variations in sampling. In Australia, the macro-fossil record has been studied extensively by palaeontologists from museums and universities dedicated to reconstructing the continents history, whereas the palaeontological record of many areas of Southeast Asia is largely known from the efforts of palynologists (palaeontologists who study fossil pollen and spores) establishing stratigraphic sequences for the benefit of the mining or construction industries. 

In a paper published in the International Journal of Plant Sciences on 25 July 2024, Edward Spagnuolo of the Department of Geosciences and Earth and Environmental Systems Institute and the Millennium Scholars Program at Pennsylvania State University, Peter Wilf, also of the Department of Geosciences and Earth and Environmental Systems Institute at Pennsylvania State University, John-Paul Zonneveld of the Department of Earth and Atmospheric Sciences at the University of Alberta, David Shaw of Biostratigraphic Associates, Aswan, Yan Rizal, and Yahdi Zaim of the Paleontology and Quaternary Geology Research Group at the Institut Teknologi Bandung, Jonathan Bloch of the Florida Museum of Natural History at University of Florida, and Russell Ciochon of the Department of Anthropology and Museum of Natural History at the University of Iowa, describe a new species of fossil Legume from South Kalimantan, Borneo, which they interpret as the only known fossil relative of the Australian Morton Bay Chestnut Tree.

Legumes, Fabaceae, play an important part of all modern tropical forest ecosystems, largely due to their ability to fix nitrogen. They are found variously as trees, shrubs, lianas and herbs, in both old-growth and disturbed forests, and produce large seed-bearing pods which serve as an important food-source for many Animals. While Legumes are an extremely diverse group in the forests of Southeast Asia, they are less dominant here than they are in  Africa or the Americas. Instead, the Southeast Asian tropical forests tend to be dominated by Diptocarps and Euphorbias, with Legumes playing a smaller role in forest composition. Nor do the group have a notable fossil record in the region, with only a few pieces of fossil wood known.

In 2014 Spagnuolo et al. collected Plant fossils from spoil heaps associated with the Wahana Baratama Coal Mine, located in the Satui Regency of South Kalimantan, Indonesia, which targets coals from the Tambak Member of the Eocene Tanjung Formation, the oldest unit of the sedimentary succession that fills the Barito and Asem Asem Basins of southern Borneo. The Tambak Member has been constrained to the Late Eocene, with a minimum age of 33.9-37.7 million years, and records a flora which pollen analysis has suggested was dominated by Palms, with Cycads, Ferns, Podocarps, Sapotaceaens, Anacoloseaens, Bombacoideaens, Knotweeds, and Blumeodendrons also present.

The new species is named Jantungspermum gunnellii, where 'Jantungspermum' is a combination of 'jantung', an Indonesian word meaning 'heart' and 'spermum', the Latin term for a seed, while 'gunnellii' honours the late vertebrate palaeontologist Gregg Gunnell. It is described from a series of large seeds measuring over 70 mm in length and over 50 mm in width, with a long suture wrapping around the seed longitudinally, and a long linear hilum (attachment scar) overlaying this.

Jantungspermum gunnellii. (A) Seed coat compression of holotype (ht) specimen (LabPal.ITB/033/BIJI/1408a; inner view of dorsal side) and seed cast of embedded first paratype (pt1) specimen (LabPal.ITB/034/BIJI/1408a) in dorsal view, showing the hilum (h) and the suture (s). (B) Seed coat compressions of holotype (LabPal.ITB/033/BIJI/1408b; inner view of ventral side) and embedded paratype (LabPal.ITB/034/BIJI/1408b; inner view of dorsal side) specimens on the counterpart block. (C) Lateral view of the holotype cast specimen (LabPal.ITB/033/BIJI/1408c) to show preserved three-dimensional seed thickness. (D) Lateral view of embedded paratype cast specimen (LabPal.ITB/034/BIJI/1408a) to show three-dimensional seed thickness. (E) Natural cast of holotype specimen (LabPal.ITB/033/BIJI/1408c) restored to the position found, fitting its seed coat, in ventral view (compare with (A) and (B)). (F), (G) Ventral (F) and dorsal (G) views of the seed cast shown in (E) (LabPal.ITB/033/BIJI/1408c). Spagnuolo et al. (2024).

Very large seeds are known in a number of Plant groups, including Palms, Laurels, Mahoganies, Soapberries, Sapotaceaens, Cashews, and Mallows. However, in shape the seeds of Jantungspermum gunnellii are quite distinctive, and can only belong to a Legume. Large seeds are also quite widespread within thee legumes, being found within the Fabaceae,  but an elongated linear hilum is only known in a single living species, the Morton Bay Chestnut, Castanospermum australe, leading Spagnuolo et al. to conclude there is a relationship between the two. However, the seeds of Jantungspermum gunnellii are significantly larger than those of Castanospermum australe, while the hilum is even more extended in Castanospermum australe than it is in Jantungspermum gunnellii, leading to the conclusion that the two should be placed in separate genera.

Second paratype specimen of Jantungspermum gunnellii (LabPal.ITB/036/BIJI/1408a, LabPal.ITB/036/BIJI/1408b). (A) Seed coat compression of specimen (LabPal.ITB/036/BIJI/1408a; inner view of ventral side), showing the hilum (h). Dorsal (B) and ventral (C) views of the seed cast (LabPal.ITB/036/BIJI/1408b), showing the suture (s). (D), (E) Side views of the seed cast. (F) Apical view of the seed cast, showing the embryonic axis (ea). (G) Basal view of the seed cast, showing the suture. Spagnuolo et al. (2024).

A large number of leaf fossils have been recovered from the Wahana Baratama spoils, all of which are interpretted as having come from Dicots. Seven different morphologies are present, with the most abundant thought likely to be from Leguminous Plants, although they do not resemble the leaves of the Morton Bay Chestnut.

Samples of rock from the Wahana Baratama spoils were analysed for palynomorphs (pollen and spores), yielding an assemblage dominated by Fungal spores, along with representatives of nine Fern families, three Monocot families, the Gymnospermous Podocarp family, and nine Dicot families, but no representatives of the Papilionoidea.(the subfamily of the Fabaceae in which Castanospermum australe is placed), nor of the Dipterocarpaceae, the family which dominates modern forests in the region. 

The palynological reconstruction suggests a swampy freshwater environment, dominated by Palms and Ferns. This is consistent with the morphology of both Jantungspermum gunnellii and Castanospermum australe; almost all modern Plants with large seeds have these dispersed by either water or Animals, and Castanospermum australe is generally interpreted as a Sea Bean (a type of Legume with water distributed seeds), although it is today found in a variety of environments across eastern Australia, having been artificially planted by Humans for much of the Holocene. This is consistent with the ancestor of Castanospermum australe having migrated from Sunda to Australia, two landmasses which have never been connected by a land-bridge, although the distance between the two in the Eocene was likely to great for the seeds of Jantungspermum gunnellii to have made the journey, making it likely that the migration was accomplished by an intermediate species.

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Investigating the illegal trade in Clouded Leopards.

The Sunda Clouded Leopard, Neofelis diardi, and Indochinese Clouded Leopard, Neofelis nebulosa, are medium-sized Felids native to tropical South and Southeast Asia. The Indochinese Clouded Leopard is found from Nepal, through Southeast Asia as far east as Vietnam and south into the Malay Peninsula, while the Sunda Clouded Leopard is found on Borneo and Sumatra. 

Both species are thought to be primarily arboreal, inhabiting tropical forests across their range, particularly lowland Dipterocarp forests, though limestone forests, upland tropical evergreen and deciduous forest, lowland seasonal and mixed deciduous forest, and peat swamp forest, all also appear to be suitable habitats. They can also survive to a degree in fragmented forests and forests with selective logging, but not Oil Palm plantations or similar environments. They are threatened by deforestation, indiscriminate hunting techniques such as hunting, as well as targeted hunting for their skins or other body parts. Both species are listed under Appendix I of the CITES Treaty, which bans trade in either live animals of their body-parts without a permit from the government of a country which forms part of the natural range. 

In a paper published in the Journal of Threatened Taxa on 26 June 2023, Anthony Giordano and Leah Winstead of the Society for the Preservation of Endangered Carnivores and their International Ecological Study, Muhammed Ali Imron, also of the Society for the Preservation of Endangered Carnivores and their International Ecological Study, and of the Department of Forest Resource Conservation at Universitas Gadjah, Rustem, again of the Society for the Preservation of Endangered Carnivores and their International Ecological Study, and of the Wildlife Ecology and Biodiversity Laboratory at Mulawarman University, Jephte Sompud of the Agroforestry and Forest Plantation Program at the Universiti Malaysia Sabah, Jayaraj Vijaya Kumaran again of the Society for the Preservation of Endangered Carnivores and their International Ecological Study, and of the Faculty of Earth Science at the  Universiti Malaysia Kelantan, and Kurtis Jai-Chyi Pei, once again of the Society for the Preservation of Endangered Carnivores and their International Ecological Study, and of the Institute of Wildlife Conservation at the National Pingtung University of Science and Technology, present the results of an investigation into the trade in Clouded Leopards, and their body parts, inspired by a social media post about a Sunda Clouded Leopard being kept by an exotic pet dealer in Indonesia in 2019.

Screen grab of a ‘pet’ Sunda Clouded Leopard Neofelis diardi on Facebook in Indonesia. Giordano et al. (2023).

Giordano et al. subsequently discovered a number of social media and local language news articles concerning the trade in Clouded Leopards, apparently without concern to the laws and government policies regulating this trade. On the basis of this, they believe that there is an active illegal trade in Sunda Clouded Leopards in Indonesia. A number of these reports included photographs of Clouded Leopards in small cages, of a kind often used at wildlife markets in Indonesia. They also discovered one incident involving an Indochinese Clouded Leopard, which was confiscated at the border between Thailand and Myanmar, having apparently been sourced from Laos. 

Screen grabs of Facebook postings: (a) Wildlife seized by Jakarta Police, including a Sunda Clouded Leopard and a Sun Bear. ( b) A posting purportedly showing a Sunda Clouded Leopard kitten for sale in Europe. Giordano et al. (2023).

Other recent studies of the trade in Clouded Leopard and wild Carnivores in general have indicated a change in the purpose for which these species are hunted, with their apparently becoming more specifically targeted for commercial reasons. Giordano et al.'s work builds upon this, providing evidence of Sunda Leopards being actively traded in Indonesia and Southeast Asia. Other species which have not historically been traded as live Animals also appear to be entering the exotic pet trade, including Small-clawed Otters, Aonyx cinereus, Smooth-coated  Otters, Lutrogale perspicillata, and Otter Civets, Cynogale bennettii. This trade appears to be at least in part driven by popular social media posts depicting these Animals as interesting 'novelty pets'. 

Two Clouded Leopards confiscated by Thai authorities en route from Laos. Here they are being temporarily cared for by the local zoo. Terry Whittaker in Giordano et al. (2023).

Interestingly, Giordano et al. only came a across a single instance of trade in the Indochinese Clouded Leopard. This is surprising, as there is known to be an active trade in other Felid species, such as Leopards and Tigers in Southeast Asia, and may indicate that the trade exists and has not been detected by this study.

The trade in large Felids has its origins in traditional practices in some parts of the world, for example in the Middle East, where Cheetahs have long been captured for use as hunting Animals, but the trade in Clouded Leopards in Indonesia appears to be a new development, and may be linked to opportunistic hunting. Widespread deforestation in Borneo has led to more conflict between Humans and forest species, and the killing of (aggressive) adult female Clouded Leopards could well result in kittens becoming available for trade as a biproduct. Whatever the source of the Animals being traded, their normalization as an exotic pets is clearly an additional threat to the species, as well as potentially to Humans handling them.

Giordano et al. recommend that governments and conservation organisations pay more attention to this trade, and focus more attention on monitoring and combating the illegal trade in Clouded Leopards. They also note the dangers to public health caused by the trade in exotic pets, observing that wild Felids are known to have the ability to carry a variety of infections potentially harmful to Humans, including Coronaviruses.

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Five new species of Staircase Snails from Borneo.

Staircase Snails, Diplommatinidae, are small terrestrial Gastropods with operculi, which get their common name from the strong ribbing on their shells, which can resemble a spiral staircase. They are members of the Cyclophoroidea, a group of Caenogastropods which have lost their combed gills and developed an internal lung independently of the Pulmonata.

In a paper published in the journal Folia Malacologia, Jaap Vermeulen of JK Art and Science and Mohd Zacaery Khalik of the Faculty of Resource Science and Technology at Universiti Malaysia Sarawak, describe five new species of Staircase Snails from Borneo.

The first new species described is placed in the genus Arinia, and given the specific name bathyodon, meaning 'deep-tooth'. The species is described from a collection of shells gathered on a limestone plateau in a primary rainforest Sangkulirang Peninsula in the Indonesian province of Kalimantan. These shells are 1.2-1.6 mm high, 0.75-0.90 mm wide, and ellipsoid-cylindrical to almost cylindrical in shape, with the last two whorls widest in frontal view. The whorls are convex, and there is a constriction of the shell before the aperture, which lacks teeth. The radial ribs are single-crested, and there are 8-12 per 0.5 mm. 

 

Arinia bathyodon: (1) Holotype, frontal view, shell height 1.6 mm; (2) same shell, right lateral view; (3) same shell, umbilical view; (4) paratype, right lateral view with part of the shell wall removed to show internal tooth. Vermeulen & Khalik (2022).

The second new species is also placed within the genus Arinia, and given the specific name congener, meaning 'of the same kind', in reference to the fact that it closely resembles the previously described Arinia similis, which is found in the same area. The species is described from a series of shells collected in the Gunung Mulu National Park in Sarawak Province, Borneo, on the path between Clearwater Cave and Moonmilk Cave. These shells are 1.0-1.2 mm in height, 0.75-0.80 mm in width, and shortly ellipsoid-cylindrical in shape, with the body whorl or last two whorls widest in frontal view. There is a constriction before the aperture, which lacks teeth. The earlier parts of the shell have 12-17 ribs per 0.5 mm, which drops to 5-7 ribs per 0.5 mm after the second half of penultimate whorl.

 

Arinia congener: (5) holotype, frontal view, shell height 1.2 mm; (6) same shell, right lateral view; (7) same shell, umbilical view. Vermeulen & Khalik (2022).

The third new species is again placed in the genus Arinia, and given the specific name semiconica, meaning 'half-cone-shaped', in reference to the shape of the shells. The species is described from a series of specimens collected at Kampong Air Putih near Samarinda, and at Gua Ambulabung in the Baay river valley on the Sangkulirang peninsula, with both localities being in Kalimantan. These shells are 1.7-2.3 mm high, 1.45-1.70 mm wide, and conical with almost flat sides, with the body whorl widest in frontal view. The whorls are convex, with the body whorl often slightly more narrowly rounded at the periphery. A constriction is present before the aperture, which lacks teeth. The ribs are single-crested with 3-6 ribs per 0.5 mm.

 

Arinia semiconica:(8) Holotype, frontal view, shell height 1.8 mm; (9) same shell, right lateral view; (10) same shell, umbilical view. Arrows indicate the position of the constrictions. Vermeulen & Khalik (2022).

The fourth new species is placed in the genus Notharinia, and given the specific name xenos, meaning 'foreigner', in reference to the fact that the genus Notharinia has previously only been identified from Laos and Cambodia, locations significantly distant from Borneo. Vermeulen and Khalik note that the genus Notharinia is similar to the genus Arinia, differing mainly in the constriction of the shell before the aperture of adult shells of Arinia, which is absent in Notharinia; something which could potentially have been lost separately in Notharinia xenos, thereby making the genus paraphyletic, but in the absence of genetic data they choose to base their diagnosis upon the available morphological data.

Notharinia xenos is described from six shells collected from limestone scarps in the upper Tatau river valley of Sarawak State Malaysia. These are 1.9-2.4 mm high and 0.85-0.90 mm wide, with cylindrical shells, slightly widened towards the base. The whorls are moderately convex, the ribs single crested and there are 8-15 ribs per 0.5 mm.

 

Notharinia xenos: (11) Holotype, frontal view, shell height 1.9 mm; (12) same shell, right lateral view; (13) same shell, umbilical view. Vermeulen & Khalik (2022).

The final new species is placed in the genus Opisthostoma, and given the specific name hemituba, meaning 'half-trumpet' in reference to the shortened shells of this species. The species is described from a series of shells collected at Gua Mardua near Kampong Pengadan on the Sangkulirang Peninsula of Kalimantan Province, Indonesia. These range from 1.6 mm to 1.7 mm in height and from 1.60 mm to 1.75 mm in width, and are shortly cylindrical to depressed conical, with the body whorl widest in frontal view. The apex of the shell is oblique and truncated. The whorls are moderately convex, and rounded, the  body whorl is rather narrowly rounded at the base, towards a constriction before the aperture. The ribs are low and thin, being widely spaced; on the spire there are 3-5 ribs per 0.5 mm, on the body whorl this drops to 2-3 ribs per 0.5 mm.

 

Opisthostoma hemituba. (14) Holotype, frontal view, shell height 1.6 mm; (15) same shell, right lateral view; (16) same shell, umbilical view. Arrows indicate the position of the constrictions. Vermeulen & Khalik (2022).

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Nasalis larvatus: Estimating the conservation status of the Proboscis Monkey on the Klias Peninsula, Borneo.

Almost half of all non-Human Primates are considered to be threatened by habitat loss due to Human activities, principally the clearing of forests for urban expansion, agriculture and agroforestry, or simply timber. Primates are thought to be particularly vulnerable to these pressures due to their long life-cycles and slow breeding rates, requiring access to a range of forest resources, which in turn makes it hard for them to adapt to changes to their environments, particularly those driven by Humans. Because of this, conservation efforts directed at Primates need reliable information on the distribution of Primates and the resources upon which they rely.

The forests of Southeast Asia are considered to be of international importance by conservations, with a number of biodiversity hotspots. These forests have come under considerable pressure in recent years, with huge areas cleared for agriculture, principally the cultivation of Oil Palms, Elaeis guineensis. Particularly threatened by this expansion are the forests of Borneo, an island with a high level of endemism (i.e. species not found anywhere else) where large areas of forest have been cleared to make way for Oil Palm plantations, and where, in addition to the direct loss of forests, many wildlife populations are additionally threatened by hunters making use of the road networks put in to support the Oil Palm industry.

Proboscis Monkeys, Nasalis larvatus, are large, sexually dimorphic Monkeys endemic to Borneo, which are considered to be Endangered under the terms of the International Union for the Conservation of Nature's Red List of Threatened Species. They get their common name from the prominent noses of the adults, these being more distinctive in the larger males than the smaller females. These Monkeys typically live in groups with a single male, plus several females and their young, although groups of young males are also found. The species is found in lowland forests close to water, such as riverine forests, mangroves and peat swamps, environments which are increasingly threatened by the expansion of Oil Palm cultivation, which is typically carried out on lowland floodplains. This expansion is known to have caused problems for Proboscis Monkeys, with their habitat increasingly being fragmented into smaller areas.

 

A male Proboscis Monkey, Nasalis larvatus, in Borneo. Mark Louis Benedict/Rainforest Rescue.

In 2004 a survey of the Klias Peninsula on the eastern tip of the Malaysian state of Sabah, found 569 individual Proboscis Monkeys living in groups, while a second survey carried out in 2005, which surveyed forests along the major rivers and tributaries of Sabah State by boat, found 818 Proboscis Monkeys on the Klias Peninsula, living in 75 groups. Both surveys found that the Klias Peninsula population was the largest surviving population in the state, and probably the only population large enough to have long-term survival prospects. This reliable presence of Proboscis Monkeys has turned the Klias Peninsula into somewhat of a tourist centre, with a number of companies offering opportunities to view the Monkeys.

In a paper published in the journal Raffles Bulletin of Zoology on 9 June 2021, Henry Bernard of the Unit for Primate Studies-Borneo at the Universiti Malaysia Sabah, Nicola Abram of Forever Sabah, Menaga Kulanthavelu and Felicity Oram, also of the Unit for Primate Studies-Borneo at the Universiti Malaysia Sabah, and Ikki Matsuda, again of the Unit for Primate Studies-Borneo at the Universiti Malaysia Sabah, and of the Academy of Emerging Sciences at Chubu University, the Wildlife Research Center of Kyoto University, and the Japan Monkey Centre, present the results of a previously umpublished survey of the Proboscis Monkeys of the Klias Peninsula, undertaken in 2014, combined with a comparison of this survey to the 2004 survey, undertaken with a view to understaning any changes in the population over a ten year period.

The Klias Peninsula has an area of about 1300 km², and is genrally flat, with a maximum elevation of about 50 m above sealevel. Historically, the peninsula was covered by complex mixture of Mangrove, Nipah Palm forest, freshwater swamp forest, and peat swamp forest, interspersed with open areas and extensive wet grasslands, but much of this has been cleared to make way for small scale Human settlements and farming, as well as larger Rubber and Oil Palm plantations. Bernard et al. carried out surveys by boat, along the Padas, Padas-Damit, Klias, and Bukau rivers, concentrating on areas where Proboscis Monkey populations had been detected by the 2004 and 2005 surveys. These included the Padang Teratak Bird Sanctuary, the Padas Damit Forest Reserve, the Menumbok Forest Reserve, the Binsulok Forest Reserve, the Klias Forest Reserve, the Kg. Hindian Forest Reserve, and the Nabahan Forest Reserve.

 

The Klias Peninsula region in western Sabah, in the northern part of Borneo (inset), Malaysia, and the research sampling sites in riverine, Mangrove, and mixed Mangrove-riverine forests along rivers in Padang Teratak Bird Sanctuary, Padas Damit Forest Reserve, Menumbok Forest Reserve, Binsulok Forest Reserve, Klias Forest Reserve, Kg. Hindian Forest Reserve, and Nabahan Forest Reserve, where the river surveys of the sleeping sites of Proboscis Monkeys were conducted. Bernard et al. (2021).

Proboscis Monkeys are almost always found close to water, favouring flooded forest environments, so boat surveys are generally the best way to survey them. These Primates return to a communal roost in a tree by a riverbank each evening, which makes surveying them relatively easy, particularly if this is done first thing in the morning, before they leave the communal roost, or late in the afternoon, after they have returned to it. Therefore, Bernard et al. carried out surveys of Proboscis Monkeys between 5.30 and 9.30 am and between 4.00 and 6.30 pm, between January and March 2014. All of the main rivers and tributaries in the study area were surveyed once only, to prevent double counting. Where waterways were close together they were surveyed on the same, or at least consecutive, days, for the same reason. A total of 106 km of waterways was surveyed, in sections ranging from 6.5 to 21.7 km. The locations of trees with Monkeys in them were recorded accurately with a GPS receiver, as were the number of Monkeys in each tree, and the type of group present (single male with females or all male group), and the type of forest the location was in (Mangrove, riverine, or mixed Mangrove-riverine). The extent of each habitat type was also recorded by length along the riverbanks, and the preference of the Monkeys for each habitat calculated from this.

Bernard et al. also carried out a number of vegetation surveys. There were carried out on 40 m circular plots, with 4-6 at each site, for a total of 34 plots. Within these plots all trees with a trunk-thickness greater than 10 cm at breast height were assessed, in order to work out the total area of all the tree stems within each plot, the largest tree within each plot, and the species richness at each plot.

To assess the amount of Human disturbance at each site, Bernard et al. used two measures; the distance from the centre of each site to the boundaries of the three closest agricultural sites, and the distance from the centre of each site to the boundaries of the three closest Human settlements.

Bernard et al. estimated the abundance of Proboscis Monkeys at each site by dividing the number of Monkeys by the area of the site, then used this measure to compare to the total area of all the tree stems within each plot, the species richness within the plot, and the size of the largest tree, as well as the distance to agricultural land and Human settlements.

Bernard et al. attempted to esitmate the loss of available habitat to the Proboscis Monkeys by calculating the potential range as being all the land 1 km inland of all the surveyed rivers, calculating the land cover throughout this area for both 2004 and 2014 using Landsat and Google Earth imagery, then calculating the change from suitable to unsuitable for Monkey habitation, based upon the parameters established by the ground surveys.

Finally, Bernard et al. calculated the amount of Monkey habitat currently within protected areas, using data from the Sabah Forestry Department, as well as the extent of the habitat outside these protected areas upon which titles have been granted for large scale plantations or other agribusiness enterprises (typically Oil Palm growth), what proportion is under Native Titile (reserved for the use of indigenous people), and what proportion is under, or available for County Lease (available for development for any purpose, and therefore again likely to be converted to Oil Palm planting), as well as land that was either no form of title, or for which the title was impossible to determine.

During 35 days of fieldwork on the Klias Peninsula, Bernard et al. carried out 42 surveys at seven study sites. They found 679 Proboscis Monkeys living in 75 groups; 44 groups comprising a males and a group of females plus their young, 16 groups of young males, and 15 groups whose composition could not be determined. The Monkeys were at their most abundant in the Padas Damit Forest Reserve in the central part of the peninsula, where there were 200 Monkeys living in 21 groups. Proboscis Monkeys were only found in Mangrove and riverine forests, giving them a total available riverbank habitat of 105 km (65 km of Mangrove forest, 35 km of riverine forest, and 5 km of mixed Mangrove and riverine forest). More Monkeys were found in Mangroves (412) than riverine forest (267), although once the greater availability of Mangroves was taken into account, this indicated a preference for riverine forests (where there were an average of 7.6 Monkeys per km) over Mangroves (where there were an average of 6.3 Monkeys per km).

Within these three forest types there was a significant variation in the vegetation, which also appeared to influence the abundance of Proboscis Monkeys. The species richness of the forests did not appear to be important to the Monkeys, but the total trunk basal area (a measure of tree maturity) was important, with more Monkeys being found where this was highest, possibly because mature trees are important for roosting sites. The closeness of Human habitation or agricultural land did not appear to be a problem for the Monkeys.

Between 2004 and 2014 the Klias Peninsula lost 11 520 m² of intact forest, most of it riverine forest (11 450 m²). In addition, 11 960 m² of degraded forest (forest which still existed as woodland but had lost much of its original biodiversity) and swampland were lost. During the same time the area of Oil Palm plantations within Proboscis Monkey habitats grew by 23 210 m², although 21 860 m² of this (94%) was later judged to be economically unprofitable due to flooding and swampy conditions.

Within the total potential range of the Proboscis Monkeys in 2014, 49% was covered by Mangrove forests, 11% by 'other forest types' (presumably riverine forest), and 18% by degraded areas and swamps, suggesting that 78% of the species total range was covered by suitable habitat and 18% by marginal habitat. The remaining parts of the range were covered by Oil Palm plantations (14%), community agriculture (7%) and aquaculture (1%), all unsuitable habitats for Monkeys.

Much of the remaining potential habitat is not protected, with only 20% of riverine forests and 59% of Mangroves having protected status (i.e. 52% of the remaining suitable environment). In addition 6% of degraded forests and swamplands are protected. This means that 80% of riverine forests, 41% of Mangroves, and 94% of degraded forests and swamplands are at risk of being lost.

Of the remaining forests, 14% (19% of the riverine forest and 13% of the Mangroves) was in Production Forest Reserves, 16 920 m² (all of it Mangroves) in Class V Mangrove Forest Reserves and 29 360 m² (11 820 m² of riverine forest and 17 540 m² of Mangroves) was in Class IV Amenity Forest Reserves, where some commercial exploitation is allowed.

About 27% of the remaining forests (including intact and degraded forests and swamps) is on land which has been granted for development. This toral includes 43% of remaining riverine forests, about 13% of Mangroves, and around 35% of degraded forests and swamps. Furthermore another 16-17% of each forest type is located on State Land, for which permits for use could potentially be issued.

 

Land use and land cover data for 2014/2015 within the 1-km buffer distance from surveyed rivers, overlaid with Proboscis Monkey sightings from the 2004/2005 and 2014 surveys, Protected Areas, and Production Forest Reserve boundaries. Bernard et al. (2021).

Bernard et al. discovered populations of Proboscis Monkeys at all of the surveys locations on the Klias Peninsula, with the largest population on the central part of the peninsula. This suggests that the area can be seen as a population stronghold for the species. The distribution of the Monkeys was similar to that observed in 2004 and 2005. The 2004 and 2005 surveys found 569 individuals in 65 groups, and 818 individuals in 75 groups, respectively, to which the 679 individuals in 75 groups found by Bernard et al. compares favourably. It is likely that the differences in Monkey numbers between the counts relate to the erratic nature of Monkey behaviour and the difficulties of surveying these primates in tropical wetland environments rather than actual fluctuations in the population, and, therefore, that the population remained fairly constant between 2004 and 2014). This would appear to correlate with the limited loss of environment suffered by the Monkeys between 2004 and 2014, during with time only 2% of riverine forests disappeared, and no Mangroves.

The Monkeys were not evenly distributed throughout their environment, apparently prefering riverine forests to Mangroves, and Mangrove forests to all other environments, including mixed riverine/Mangrove forests (although the avoidance of this later environment might be an artefact, as onlu 5 km of this environment was surveyed during the study). Studies in other areas have suggested Probiscis Monkeys prefer riverine forests to either Mangroves or mixed riverine/Mangrove forests, probably due to a higher plant diversity and greater variety of food in this habitat, although Mangroves are still clearly also an important habitat.

The presence of large trees appeared to be particularly important to these Monkeys, probably because of their role as roosting sites. Larger trees both provide a greater number and variety of nesting sites, but also provide a greater distance between these sites and the ground, making it harder for predators to reach the resting Monkeys undetected.

The study did not find any direct impact on Proboscis Monkey populations made by the proximity of Human settlements of agriculture, although this may have been due to the small size of the survey. The largest threat to wildlife populations on Borneo is currently considered to be the expansion of Oil Palm plantations, and, as with other Primate species, Proboscis Monkey's tend to avoid these environments, which are comprised of extensive monocultural stands of an unfamiliar fruit tree. Other than this however, Proboscis Monkeys seem to be relatively tolerant of the presence of Humans, and will even roost close to Human settlements if that is where suitably large trees are to be found. 

Little forest was lost on the Klias Peninsula between 2004 and 2014, but there is clearly the potential for much more to go, with the 28% of riverine forest currently designated for development being of particular concern. Grants of land made under such schemes in Sabah come with time limits; i.e. if the holder does not use the land within a certain period of time, then they lose the title, which can be granted to another user. These schemes currently make no provision for the retention of intact forest, clearly creating an incentive for developers to fell such forests to retain control of the land. As such Bernard et al. strongly recommend that the law be changed to allow landowners to leave areas of forest intact in order to protect the Proboscis Monkeys.

Also of concern are the large areas of forest designated as Production Forest Reserves, particularly the area within the Padas Damit Class IV Amenity Forest Reserve, which is the area with the greatest population of Proboscis Monkeys. These areas were originally intended to be areas of forest which were left largely intact, but where a range of leisure activities were permitted, however a follow up study in 2017-18 found that large areas under this designation had been converted to Oil Palm cultivation.

Proboscis Monkeys require forests along river margins to survive. As such the fragmentation of such environments not only lowers the amount of available habitat, but also removes their ability to move from one area to another, as their preferred environment is essentially linear. Thus protecting the species in future will require not just careful monitoring of their population, but careful management of the areas where they live, and in particular careful monitoring of land use changes likely to have an adverse effect.

Bernard et al. feel it would be particularly useful to grant full protection to Proboscis Monkeys living on government land, as this would have the issuing of land grants within areas of Monkey habitat, and allow the designation of protected areas to protect the Monkeys.

The Klias Peninsula is a popular tourist destination, and viewing Proboscis Monkeys is a popular activity with tourists. Thus good management of the Monkey population is likely to be of economic as well as conservational benefit, drawing tourists to Sabah, and generating income for local communities.

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Helarctos malayanus: Understanding the impact of Palm Oil plantations around the Tabin Wildlife Reserve on Malayan Sun Bears

Wildlife reserves around the world are coming under increasing pressure due to rising Humans populations and activities in adjacent areas. Originally conceived as refuges in which the core habitats of threatened species would be preserved, surrounded by buffers of limited activity, many of these reserves now have intensive Human activities extending directly to their boundaries, provoking a rise in Human-wildlife activities, both as Humans enter parks to hunt or extract Plant or mineral resources, and as Animals on the boundaries of parks try to take advantage of Human resources, by crop raiding or hunting livestock.

Populations of Animals in parks are therefore becoming particularly prone to edge effects, with Animals populations living close to reserve boundaries particularly prone to extinction. This is particularly true for Animals living on smaller reserves, and large carnivorous Animals, which require larger territories and are more vulnerable to Human-wildlife contacts.

Wildlife in Southeast Asia is increasingly vulnerable to a range of anthropogenic threats, driven largely by deforestation. More than 50% of tropical forests in Southeast Asia have been felled for agriculture and other commercial purposes. As well as the direct loss of habitat, many wildlife populations have become more vulnerable to hunting, as new road networks open up formerly remote areas. This hunting is driven both by the desire to obtain bushmeat for local consumption, and the international wildlife trade, in which both whole Animals and Animal body parts are traded over long distances across international boundaries.

Sun Bears, Helarctos malayanus, are hunted for their paws and gall bladders, which have high commercial values on the international market. The species is found in the evergreen forests of the Sundaland sub-region and the seasonal forests of mainland Southeast Asia. Sun Bears are currently classified as Vulnerable under the terms of the International Union for the Conservation of Nature’s Red List of Threatened Species, but their populations are thought to have declined by 30% in the last 30 years, due to a combination of habitat loss and hunting for body parts, making it likely the species will be reclassified as Endangered in the near future.

 

A Borneo Sun Bear, Helarctos malayanus euryspilus, in Sabah State, Malaysia. Sunbear Survival.

Efforts to set up conservation plans for Sun Bears have been hampered by a lack of information about their distribution, ecology, and population structures, and while some work to improve our understanding of this has been undertaken in recent years, there is still much about the species that is not fully understood. Notably, it was long thought that Sun Bears were restricted to undisturbed primary rainforests, but recent studies have suggested that they are also found to some extent in secondary forests and even areas that have recently been cleared by loggers.

The impact of land-use changes upon vulnerable species has been little studied in Southeast Asia, although, as in other areas, these impacts are likely to be severe when they are close to reserve boundaries, as such encroachments will lead to increased Human-wildlife conflicts, enhanced opportunities for poachers to target wildlife, barriers to the movement of species between remaining areas of habitat, and changes in Animal behaviour in changing environments. In Malaysia there has been a rapid spread of monocultural Oil Palm plantations into many areas previously covered by pristine rainforests, with a subsequent negative impact on wildlife populations. There plantations have a severe impact on Mammal diversity, with the number of species declining rapidly away from areas of natural forests. Nonetheless, many species have found ways to exploit these new environments, and Sub Bears, which are generally diurnal, are known to make nocturnal foraging forays into Oil Palm plantations. Such crop-raiding behaviour gives the Bears access to a highly nutritious food-source, but fuels conflict with villagers and plantation workers. This in turn tends to lead to a rise in poaching, typically by snaring, which leads to boundary areas becoming population sinks, as Bears in these areas are drawn into the plantations to access the new food source, where they become more vulnerable to poaching.

In a paper published in the journal Wildlife Biology on 3 May 2021, Thye Lim Tee of the Department of Biological Sciences at Sunway University, Frank van Manen of the Interagency Grizzly Bear Study Team at the Northern Rocky Mountain Science Center, Petra Kretzschmar of the Department of Evolutionary Ecology at the Leibniz Institute for Zoo and Wildlife Research, Stuart Sharp of the Lancaster Environment Centre at Lancaster University, Siew Te Wong of the Bornean Sun Bear Conservation Centre, Sumbin Gadas of the Sabah Wildlife Department, and Shyamala Ratnayeke, also of the Department of Biological Sciences at Sunway University, present the results of a study which used remote cameras along a gradient across the boundary of the Tabin Wildlife Reserve in Sabah State, Malaysian Borneo, to determine the presence or absence of Sun Bears in landscapes subject to Human alteration.

The Tabin Wildlife Reserve is an area of lowland Dipterocarp rainforest northeast of Lahad Datu. It was created in 1984 for the conservation of the Sumatran Rhinoceros, Dicerorhinus sumatrensis, and now represents the largest contiguous forested area in Sabah, although it is surrounded by Oil Palm plantations. Rainfall in the reserve averages 150–300 cm per year, and temperatures from a mean daily maximum of 32.0°C to a mean daily minimum of 22.0°C.

 

The Tabin Wildlife Reserve preserves an excellent habitat for forest-dwelling Bornean species, but Oil Palm plantations now extend to its boundaries on almost all sides. Google Maps.

Tee et al. used data from two sources in their study; the first was collected during Sumatran Rhino surveys at Tabin Wildlife Reserve from July 2012 through February 2013, and the second carried out by Thye Lim Tee April–October 2017. Only data from independent camera sites that were located at least 1 km apart was used in the study, with sites that were closer being omitted, resulting in a total of 83 camera sites being included in the study. 

The 2012-13 Rhino surveys were conducted in the central and northern part of Tabin Wildlife Reserve, with cameras placed within 6 km² square grid cells based on a minimum home-range size of Sumatran Rhinos at game trails, mud wallows or hill crests. This study yielded data from 39 cameras with an average distance of 1.7 km. These camaras operated 24 hours a day for an average of 96 days.

During the 2017 study 44 passive infrared remote cameras were deployed along forest trails, the reserve boundary, old logging roads and within the core area of the reserve. These cameras were separated by an average distance of 1.4 km, selected to establish a gradient in relation to landscape features of interest, such as distance to roads and reserve boundary, with cameras placed to optimise Sun Bear detection, and baited with Shrimp paste and pieces of salted Fish placed in black shading net. These cameras were deployed at each site for 28 days, before being moved to a new site, with 13-18 cameras active at any one time.

Tee et al. used a linear model to correlate landscape features with Sun Bear presence, judging Sun Bears as present in an area based upon camera sightings, bait removal, or claw marks on trees. Bears were assessed as being present if they were detected once within the entire period of observation, with no finer differentiation than either present or absent, as the species is somewhat cryptic in its habits, and hard to detect. The presence or absence of Bears was then compared to seven other landscape variables; (1) elevation, (2) terrain ruggedness, (3) distance to nearest road, (4) distance to nearest permanent river, (5) distance to nearest reserve boundary, (6) human density and (7) percentage natural forest cover. The results were mapped in Quantum GIS, using elevation data from the Shuttle Radar Topography Mission, Human density data from the LandScan 2007 global population data set, road data from Google Earth Pro, combined with data obtained by mapping with a Garmin GPSmap 62s Global Positioning Unit, and other data from previous studies carried out in the area. Because Oil Palm plantations extend to the boundaries of the reserve on all sides, all areas outside the reserve were considered to have 0% natural tree cover. Statistical processing was carried out using the R software package.

Distribution of 83 remote camera stations and Sun Bear presence or absence during two remote camera surveys in Tabin Wildlife Reserve, Sabah, Malaysia, 2012–2013 (circles) and 2017 (triangles). Black circles or triangles indicate sites with Sun Bear presence, whereas white circles or triangles indicate sites with no detection of Sun Bears. Tee et al. (2021).

Tee et al. made 164 independent Sun Bear sightings over a total of 4862 study-nights, with Bears being sighted at 47 of the 83 sites included in the study. Distance from road was found to be the most reliable indicator of Human disturbance, as roads effectively run around all the boundaries of the reserve. Bears were found to be most active away from these boundary areas, with 138 of the 164 Bear-detections occurring at 35 of the 51 sites designated as 'core areas', while 26 sightings occurred at 14 of the 32 sites designated as 'boundary areas'. Thus Bears were 3.3 times more likely to be sighted in 'core areas' than 'boundary areas'. Sun Bears were most active at around 7.00 am and 4.00 pm in the core areas, whereas in the boundary areas they were most active between 5.00 am and 6.00 am. 

 

Predicted relative probability of sun bear presence in Tabin Wildlife Reserve, Sabah, Malaysia, based on remote camera data collected during surveys in 2012–2013 and 2017. Predictions from seven logistic regression models were multiplied by their respective AICc weights and summed to obtain model-averaged probabilities. Model covariates included distance to nearest road, elevation, human density, percent natural forest cover and survey. For models that included the survey covariate, we averaged predicted values for the two equations representing each of the two survey periods. Tee et al. (2021).

Sun Bears were found to be most present in areas away from roads, at higher elevations, and with lower percentages of natural forest cover. However, the degree of elevation present in the Tabin Wildlife Reserve is limited, with the highest parts, in the centre of the park, only reaching 571 m above sealevel, and the elevation falling to 20-100 m at the reserve's boundaries. Higher elevation was also closely correlated with terrain ruggedness, although the correlation between Bear-presence and terrain ruggedness, was much lower than that for elevation. Tee et al. suspect that the correlation between Bear-presence and elevation may actually reflect some variable not measured in their study. In particular they note that the flora of low-lying areas within the reserve is relatively uniform, but that tropical forest floras often vary considerably with even small changes in elevation, which may suggest that the Bears may be responding to the availability of some resource, such as food or cover. Bears were also found to be found in areas with lower levels of natural cover, although this measure appeared to have been skewed by the activities of Bears in the boundary areas, with those Bears detected here being predominantly detected close to the boundaries with Oil Palm plantations, 

Tee et al. had a higher detection rate for Sun Bears than previous studies carried out at other reserves in Sabah. This was particularly notable for the baited sites, but also true of the sites from the 2012-13 Rhino survey, which Tee et al. take to indicate that Sun Bears are present at higher densities in the Tabin Wildlife Reserve than in other reserves in Sabah, which in turn probably relates to the size of the reserve, which preserves a larger fragment of forest that any other reserve on Sabah, all of which are impacted by the spread of Oil Palm plantations. 

The greater activity of Sun Bears during twilight hours in boundary areas of the reserve is almost certainly an indicator of crop-raiding activities by these Bears, with previous studies having indicated that such crop-raiding is almost exclusively nocturnal, with Bears returning in the forests during the day. Bears appeared only to venture close to roads in areas where this was associated with access to Oil Palm plantations, with Bears generally avoiding roads in the interior of the reserve. 

Overall, Tee et al.'s findings are consistent with previous studies, which have found that Human activities, and in particular the spread of Oil Palm plantations, have had a strong negative impact upon the lives of Sun Bears, and that the species will tend to prioritise avoiding contact with Humans above all other activities, including foraging for food.

Studies of other Bear species have detected a similar aversion to roads, with Sloth Bears, Melursus ursinus, in Sri Lanka, having been shown to avoid areas with roads completely, and Brown Bears, Ursus arctos, avoiding roads with high traffic levels and Human settlements in general. Bears are intelligent Animals, and can modify their behaviour to accommodate Human activities, but the presence of roads is strongly associated with rises in Bear-poaching and other forms of Human-Bear conflict, which have a negative impact on Bear populations. This is of particular importance for the Tabin Wildlife Reserve, where there is no control on access from roads abutting the reserve, nor any form of anti-poaching precautions in place. Poaching in the area is known to be highly profitable, with poachers targeting both protected Animals and Plants (such as the Agarwood Tree, Aquilaria spp.). Tee et al. photographed groups of armed poachers within the reserve on three occasions, all within 1 km of a plantation road. 

Malaysia is the world's second largest producer of Palm Oil, and Sabah produces about 27% of the country's total output. Unsurprisingly, Sabah is also a global deforestation hotspot, with 15 000 km² of Oil Palm plantations, out of a total land area of 74 000 km². This expansion of Oil Palm plantations has been accompanied by an expansion of the infrastructure which supports such activities, most notably roads. In an area such as the Tabin Wildlife Reserve, which is surrounded by plantations and roads on almost all sides, simple passive protection of species such as Sun Bears (i.e. declaring these species to be protected and hoping people will comply with this) is unlikely to be effective, and a more robust species protection plan will need to be put into place if these Animals are not to go extinct. Any such species protection plan needs to be built upon studies of hunting and poaching in the area, and the responses of Bears to Human activities, and include rigorous anti-poaching measures and formal partnerships between locally-based non-governmental organisations, local ecotourism resorts, plantation stakeholders and local communities.

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