Bearded pigs are important in both culture and in the economy to the rural communities of Borneo. The meat is preferred over many other options by local people and therefore it is one of the most frequently hunted wildlife species. Improved access into the forests and destruction of their natural habitats by logging and agricultural activities have increased hunting pressure on the Bearded pigs. Through logging, it is probable that availability of their food and of course their habitat - for foraging and breeding - is being reduced. Though the response of pigs to logging, and how habitat degradation effects diet and habitat is unknown. There is increasing evidence that these pigs are dependent on the survival on tropical forest, which are well known to be in considerable decline, especially due to expanding plantations, fires and logging.
The unsustainable logging of dipterocarps in Bornean forests is changing the underlying ecology of the island, which probably means that bearded pigs will not have the mass peaks in population numbers as observed during the 1950's and 1980's. Additionally, the fragmentation of Borneo's forests will allow increased invasion other pig species, which might displace S. b. barbatus from much of its former range. Documented large increases in bearded pig numbers, with maximum reproduction and population growth, may be linked to in back-to-back and large mass fruit crops over an extended time periods. These areas will become rarer as areas are deforested, reducing contiguous forest cover, and will also become rarer with climate change.
As bearded pig populations decline, the impact of hunting for meat, once probably sustainable in many areas, is becoming much more serious, and hunting is probably now a serious threat in many places.
This is one of the most commonly recorded mammals in our camera trapping project, with 168 records to date. Females and juveniles often travel together but males are usually solitary. Litters can range from 2-5 piglets.
Bearded Pigs are regularly hunted for meat in the Sabangau forest, and our monitoring data show that 8% of all hunters visiting the forest are targeting pigs.
The Bearded Pig is found in the Malay Peninsula, Sumatra, Bangka (where its continued presence is uncertain), and Borneo (Brunei, Sabah, Sarawak and Kalimantan), extending to Siibuto and Tawitawi Islands in the Sulu Archipelago. The species is apparently most widespread on Borneo, which might hold the bulk of the population.
Bearded pigs consume fruit and roots from at least 50 genera and 29 families of plants. Fruit supply is believed to have particular influence in determining growth rate, fat deposition and reproduction. They also feed on invertebrates (in soil and rotting wood), fungi, small vertebrates and carrion.
Bearded pig populations can exist in various types... That in Sabangau is typically a dispersed, static populations exploiting small, dispersed, unpredictable and discontinuous 'background' food sources. Low breeding and growth rates are possible in these conditions. the population generally only moves locally (e.g., typical mixed dipterocarp forest in Borneo between generalized fruiting episodes).
2. Small to medium populations exploiting concentrated, predictable and continuous 'target' food sources. High breeding and growth rates possible. Local movements only (e.g..Koompassia-Burseraceae forest in Malaya).
3. Small to medium populations, with members aggregating to exploit large, dispersed, unpredictable food sources. Breeding and birth rates depend on success of matching movements to fruiting within a dynamic phenological mosaic. Short to medium-range movements (e.g., typical mixed dipterocarp forest in Borneo between generalized fruiting episodes.
4. Small to large populations moving regularly to exploit concentrated, predictable and discontinuous target food sources. Breeding and growth linked to activity of food sources. Short-range to long-range movements. Size of population varies from year to year depending on background food supply (e.g., Dinochloa association in Sabah, orDryobalanops aromatica association in Peninsular Malaysia).
5. Large and expanding population exploiting an exceptional supply of background food available over a period sufficient for several litters to be raised to sexual maturity. High breeding and growth rates characteristic. Long range movements (e.g., interior of Sarawak in 1954, 1959, 1983 and 1987).
6. Very large and collapsing population having exceeded background food supply. Low breeding and high death rates. Increasingly desperate long-range movements (e.g., starving herds reported from Peninsular Malaysia and Borneo).
The basic social structure is that of the major social unit being the mother family, a female and her litter. These units often join up, and much larger aggregations are formed occasionally, with scores or even hundreds of pigs traveling together. Fully adult males seldom associate with the natal groups. Age at first pregnancy presumably varies in the wild from about 10-20 months. In any one area, the rut coincides with synchronized flowering in the forest, with the timing being centered on the transition between late flowering and early fruit formation. Falling petals therefore offer a potential visual cue. A certain nutritional status may have to have been attained by females before they become responsive to whatever stimulus acts to trigger mating. Pregnant females had a median fatness index (finger-widths of fat depth at the shoulder) of 1.5, while rutting males scored zero by this measure (n = 19, 32).
Gestation length is not known but is estimated at 90-120 days, based on the interval between rut and the ensuing birth-peak. Birth occurs within a nest, which is constructed of vegetation by the mother, and which is occupied by her and the new piglets for a week or so. Data from hunter interviews indicated that the median number of piglets accompanying an adult female (n = 53) was 7, which was the same as the median number of fetuses counted in dead females (n = 8). Abbot in Davies (1962) reported a slightly higher median of 9 fetuses per female (n = 5). Litter size is very variable in part because of the influence of female size: small mothers typically have 3-4 piglets in a litter, while large ones have 10-12. Elsewhere, the range in litter size has been given as 3-11 piglets (National Research Council, 1983).
Fat reserves in the mother are used up quickly during lactation, and females accompanied by small piglets are almost invariably thin or very thin. Those with large piglets are fatter, and have presumably gained weight after weaning. This fattening process seems to depend on what fruit is available, with dipterocarp seeds and acorns having most impact. If these are abundant, it seems likely that two litters can be raised by a female within a year.
Sunda Pangolin Manis javanica
This species ranges over much of mainland Southeast Asia, much of Thailand, central and southern Viet Nam, Cambodia and through Indonesia - to Peninsular Malaysia, to Sumatra, Java to Borneo (Malaysia, Indonesia, Brunei). The northern and western limits of its range are poorly known. The species historically occurred throughout Thailand but has since been lost from much of the lowland areas due to human agricultural expansion and hunting.
In Viet Nam, there are records from throughout the central and southern parts of the country. The species is evidently widespread in Lao PDR, with recent records from a wide range of areas below around 600 m altitude, with the possibility that in Lao PDR the species is restricted to the Mekong plain and adjacent foothills to around 900 m, The species is widespread in Peninsular Malaysia, primarily in forest, but also in gardens and plantations, including rubber, it is still found in the wild in Singapore and is notably widespread on Borneo, from sea level to 1,700 m on Mount Kinabalu in Sabah. In Indonesia, the species is widespread on Sumatra, Java, Borneo.
it appears to be absent from the extensive peat swamp forests of Sarawak (CITES 2000). In Sabah, the species is rarely seen, although is evidently widely distributed, being known by local people throughout Sabah.
Virtually no information is available on population levels of any species of Asian pangolins. These species are rarely observed due to their secretive, solitary, and nocturnal habits - in general enough research on population densities or global population are yet to be produced. There appear to be no comprehensive population estimates available, although records are reportedly rarer in many range states.
The sunda pangolin is one of four Asian pangolin species (there are also four in Africa). Solitary and arboreal, the species is found in primary and secondary forest, and is found in cultivated areas including gardens and plantations, including near human settlements. They can be found in a variety of habitats, though areas with primary forest support most individuals, probably because they contain more older, larger trees with hollows suitable for sleeping and for use as den sites
A specialized feeder on ants and termites, it is probable that one young is born at a time, after a gestation period of at minimum of around 9 weeks.
Manis javanica is a more arboreal species than some other species and adept climbers, with prehensile tails. They often climb to access ants nests in trees. They sleep in hollows either in, or at the base of, trees, rather than excavating their own burrows in soil as Manis pentadactyla does.
Home-range size has been estimated at 6.97 ha, moving peaks in activity between 03h00 and 06h00.
OuTrop is involved in the newly re-established IUCN Pangolin Specialist Group with the iam of raising awareness about this charismatic animal and contributing new data to help conserve this species.
Bornean yellow muntjac Muntiacus atherodes
As the name suggests, the Bornean yellow muntjac only occurs on Borneo, living throughout the island in many specific locations. Presumably living in Brunei , it is known to be present in both Indonesia (Kalimantan) and Malaysia (Sabah and Sarawak). The Bornean Yellow Muntjac is known from most of the forest protected areas in Sarawak, and has been recorded in logged forest and in oil palm adjacent to recently logged forest. Yellow Muntjac are known from many protected areas in Malaysia and Indonesia. Protected area coverage in the lowland plains is still relatively limited in Borneo, and many areas are, in terms of forest ungulate protection, sufficiently small (under 100 sq. km) that long-term persistence cannot be assumed . The long-term persistence of large populations of Bornean Yellow Muntjac, as distinct from isolated populations in well-secured protected areas, will depend upon their ability to use plantation landscapes of oil palm, rubber, acacia and others. Clarification of this is needed to assess the species’s conservation priorities. M. atherodes may be more a species of old-growth forest and M. muntjak the predominant species of logged areas (Heydon 1994). It is urgent to determine whether this is a generally applicable pattern across Borneo.
This species appears to be widespread and common throughout its range, as long as appropriate habitat occurs. Numbers seem to be in some decline in the Indonesian Borneo where OuTrop work. the two species of muntjac are also in decline in Malaysian Borne, though which one is suffering the most is unknown.
It seems the Bornean Yellow Muntjac is absent from mountains. It is common in Sungai Wain forest, Kalimantan, which spans 30–150 m asl, where it clearly outnumbers M. muntjak. It also likely to be the predominant species in Sarawak Planted Forests, where it uses mature and immature plantation, freshly logged forest and relict tall forest; nearby it has also been found in oil palm . Muntiacus atherodes uses both primary and secondary forest, though it is unknown how tolerant it is to severe degradation and fragmentation.
Muntiacus atherodes eats herbs, seeds, grass and fruits and is mostly active during the daytime though sometimes at night as well. It lives in small territories and moves either in pairs or alone though it’s breeding seasonality remains unknown.
The Yellow Muntjac is currently listed as Least Concern by IUCN, an assessment based on few precise data and which will warrant review when a clearer picture is available. Threats and rates of decline are poorly understood and far more data are needed to make an informed decision on the status and ecology of this species. This species is generally considered to be widespread and at least locally common.
Habitat encroachment and hunting are both widespread on Borneo. Indeed, they are often associated and all the island’s ungulates, which suffer from the increased hunting that often accompanies logging. Hunting can causes local extinctions, badly affecting ungulate numbers. Hunting is mainly for meat, medicine and hides. M. atherodes has survived at least for several years in several areas of isolated forest. The current carving up of the formerly extensive forest of lowland Borneo is recent, so that determining long-term persistence in such fragments is not yet possible. Slow but fixed declines may account for records in fragmented and degraded areas, in which case these populations may not survive.
Sambar Deer Cervus unicolor
The appearance and the size of sambar vary widely across their range. Males have large, rugged antlers forked at the tip and around 43 inches in length. The colour of the shaggy coat can be anything from yellowish-brown to dark grey in colour, along with a small but dense mane - more prominent in males.
Adult males and pregnant females exhibit some hairless, blood-red spots located about halfway down the underside of their throats. This sometimes oozes a white liquid, and is apparently glandular in nature. Things like this are unusual in mammals and still need extra study.
Sambar are nocturnal or crepuscular – meaning they are mostly active at dawn and dusk. The males live alone for much of the year, whereas females live in small herds of up to sixteen individuals. In some areas, though not in Sabangau, the average herd consists of only three or four individuals, typically consisting of an adult female, her most recent young, and perhaps a subordinate, immature female. Some deer more commonly live in larger groups, so the seemingly solitary behaviour in peatswamps contasts these populations. They often congregate near water, and are good swimmers. As is well known for Deer, sambar are generally quiet and elusive. Adults do scream or make short, high-pitched sounds when alarmed, more commonly communicating by scent marking .
Stags scent mark by wallowing and dig their antlers in urine soaked soil and then rub against tree trunks. Sambars ability of standing on their hind legs – bipedalism – is rare and quite remarkable for a deer species. Staga will also scent mark himself by spraying urine directly in his own face with a highly mobile penis. Females readily defend their young from most predators, another behaviour which is relatively unusual among deer. Sambar will lower its head with an erect mane and lash at predators including dogs. Several sambars may form a defensive formation, touching rumps and vocalising loudly at dogs. When there is danger, sambar will stamp its feet and make a ringing call known as "pooking" or "belling".
Sambar with mate and reproduce all year-round, with calving occurring on a seasonal basis. The male establishes a territory, to which he attracts nearby females. The male stomps the ground, creating a bare patch, and often wallows in the mud. Females moving widely among breeding territories seeking males to court.
Large dominant stags will defend non-exclusive territories surrounded by several smaller males which they have bonded and formed alliances with through sparring. When sparring with rival males, sambar lock antlers and push, like other deer. They are known to use their bipedal skills to sometimes stand on their hind legs and clash downward into each other, similar to some species of goat-antelope. Females also fight, standing on their hind legs and use their forelegs to hit each other in the head.
Sambar primarily live in woodland and feed on a wide variety of vegetation, depending on the local habitat. Sambar have been seen congregating in large herds in protected areas such as national parks, but this behaviour has not been seen in Borneo.
The sambar inhabits much of southern Asia (as far north as the south-facing slopes of the Himalayan Mountains), mainland Southeast Asia, southern China, Taiwan, and finally the islands of Sumatra and Borneo in Indonesia.
Sambar are found in habitats ranging from tropical seasonal forests (tropical dry forests and seasonal moist evergreen forests), subtropical mixed forests (conifers, broadleaf deciduous, and broadleaf evergreen tree species) to tropical rainforests.
Sambar are often found in dense foliage cover, though the exact nature of this varies considerably with the environment, which themselves vary across their wide range throughout southern Asia. They are usually within reach of areas of water – there’s no lack of water in the peat swamps of Sabangau! Home range sizes are most likely also considerably variable depending on the habitat.
The Sambar is in rapid decline, due to habitat loss and hunting. In Sabangau, the Sambar Deer appear to be absent from areas that have previously been subject to higher hunting pressure. Indeed, all of Borneo’s ungulates suffered from the increased hunting that often accompanies logging. Overall these pressures have led to a many local-level extinctions throughout its range, and its occurrence at low densities in most areas.
Their main natural threats are tigers and Asiatic lions, both not applicable to Borneo. They also can be taken by crocodiles, mostly mugger crocodiles in India. The degree of hunting by water based predators will be very low if any at all. Leopards largely predate only young or sickly deer, though can attack healthy adults as well – it is suspected that hunting from clouded leopards is low
Greater Mouse-deer / Greater Oriental Chevrotain Tragulus napu
The greater and lesser mouse-deer are relatively similar in appearance, especially
Tragulus napu occurs in the Sundaic subregion, extending some way up the Thai–Malay peninsula, in Brunei, Indonesia, Malaysia, Myanmar, Singapore and Southern Thailand.
Caution is needed in interpreting modern records of T. napu from anywhere outside the specimen- and photograph-validated range .
Greater Oriental Chevrotain populations are not well studied – it occurs almost in all areas with the Lesser Oriental Chevrotain – they occur in almost complete sympatry.
They are common in Borneo and - the genus is commonly camera-trapped and can also recorded by signs on Sumatra and in West Malaysia. Their populations can reach quite high densities in primary habitat becoming more scarce in selectively logged areas, where marked decreases have been noted. As decreases in population numbers are similar to other ground mammal decreases in numbers, the decline in chevrotains probably reflects habitat factors rather than the secondary complication of increases in hunting.
Hab & ecol
The Greater Oriental Chevrotain is almost completely sympatric with T. kanchil - meaning the two species overlap in almost all areas with this other species, but the degree of exact overlap within ranges is less clear. In the lowlands of Borneo both occur but T. napu apparently ranges to higher altitudes than does the latter.
Much more information about the chevrotain habitat and use of areas is desirable before firm species-level conclusions can be drawn. T. napu was found typically to range 19ha in old logged forest and 7 ha in primary forest, this difference again suggesting an important association with primary forest.
It is suspected that chevrotains may rely almost entirely on fruit in their diet - obligate frugivory. This may limit their ability to compensate for loss of fruit trees, often browsing the more abundant regrowth of logging areas. They have a limited resilience to human presence, presumably the effects of humans and their hunting activity on the forest.
The genus (presumably including this species) was ubiquitous in a study of virgin jungle reserves in West Malaysia. The ability of T. napu to use plantations is probably low, because research - although limited - agrees that it does not persist well in secondary or logged forest.
Tragulus spp. are generally thought to be nocturnal, and at two sites in Borneo, they comprised over half the contacts of spot-lighting surveys. Competition with T. kanchil is not pronounced.
Birth to one or, rarely, two young, which reach sexual maturity at 4.5 months. Animals live up to 14 years. The female can be pregnant throughout her adult life, only a few hours at maximum before becoming pregnant again . The young are born fully developed, and can stand within 30 minutes of birth. Mothers nurse their young standing on three legs. They are generally solitary
Hunting and habitat loss occur at high levels almost throughout Greater Chevrotain’s range, but the species is said to be relatively resilient to hunting and habitat loss.
However, few data have been found to support this assessment, particularly because most studies have not conclusively differentiated between the two species. The majority of evidence to show this did not identify chevrotains to species. The genus is defiantly widespread and common though the degree of T. napu remains unknown as the species is rarely identified past genus. There is some evidence to show that the species is not very adaptable to forest degradation.
Pressure from hunting is relatively low compared to commercially used animals, though Chevrotains are among the most favoured wild meat by inhabitants of some forest areas.
Lesser Mouse-deer / Lesser Oriental Chevrotain Tragulus kanchil
The Lesser Oriental Chevrotain occurs in Borneo, Sumatra, the Thai–Malay Peninsula, many islands within the Greater Sunda region, and continental South east Asia north, including the countries of Indonesia, Malaysia, Brunei, Singapore, Myanmar, Thailand, Cambodia, Lao PDR, and Viet Nam.
The Lesser Oriental Chevrotain populations are not well studied, as the genus does not gain much research attention, coupled with difficulties confirming how much of the information on the genus relates to specifically this species. T. kanchil seems to be relatively common, at least on Borneo. It is generally more common than Greater Oriental Chevrotain, studies and sightings are few and national population status or trends can not yet be determined.
This species is found in lowland or foothill primary and secondary forests but can also be comfortable in some cultivated areas. The most common habitat used is a mosaic of riverine, seasonal swamp and dry country, vegetated mostly by dipterocarp tree species.
During the day, areas with dense undergrowth are used, moving to higher and drier ridge areas at night. All Tragulus species are strongly associated with forests, with strong evidence that this species can do well in young forest. It uses disturbed habitats a relatively large amount, with some evidence for strong association with immature forest. It has been documented to be initially more common in logged forests than in mature forests, with numbers decreasing as logged forests matured.
The Lesser Chevrotain may even be able to survive in large numbers in plantation landscapes: in the Sarawak Planted Forests, Bintulu, Sarawak, Belden Giman (pers. comm. 2008) has many records from Acacia mangium plantations both mature and immature. However, this landscape contains many patches of secondary and old-growth forest (Belden et al. 2007), so further study is needed to assess use, if any, of landscape-level monocultures.
Most of this chevrotain’s geographic range is dominated by evergreen or semi-evergreen forests, but large areas of Cambodia, Thailand and to a lesser extent Lao PDR and Viet Nam are deciduous. One survey in Mondulkiri province, Cambodia, in 2008, found chevrotains to be widespread and common in mixed deciduous forest, dominated by e.g. Lagerstroemia spp., but they were not found in nearby deciduous dipterocarp forest (C. Starr pers. comm. 2008). In this same general area, J. Walston (pers. comm. 2008) also found them commonly in mixed deciduous forest, during 2002–2006. Field surveys of extensive landscapes of deciduous dipterocarp forest and mixed deciduous forest (in which ground fires are almost annual) in eastern and northeastern Cambodia (including Mondulkiri) have not detected the species (R.J. Timmins pers. comm. 2008) and camera-trapping from the same landscapes also suggest chevrotains are absent from deciduous regularly burnt forest tracts, but occur in semi-evergreen forest patches within the same landscapes (WWF unpublished data). Dumas (1944) stated that chevrotains were unknown in the deciduous dipterocarp forests of Cambodia, No other information on their use of deciduous landscapes has been traced; it is probable that even within deciduous dipterocarp they might use the semi-evergreen riverine strips within.
The Lesser Oriental Chevrotain may be absent from highlands throughout much of its range, and seems to be an extreme lowland specialist in some areas. The clearest analysis, from Borneo, found that it lived mostly below 100 m asl, with no record above 600 m asl (Payne et al. 1985). The maximum altitude in Indonesia (i.e. Borneo and Sumatra) is also said to be 600 m asl (G. Semiadi and Boeadi pers. comm. 2006); specific information from Sumatra has not been traced. In Lao PDR most known sites (see Duckworth et al. 1994; Duckworth 1996; Evans et al. 2000) are also below 600 m asl; however, chevrotains are abundantly hunted in the Nam Ha NPA which has a minimum altitude of 560 m asl (and rises to nearly 2,100 m asl) and is almost entirely rugged (Johnson et al. 2003), although these are perhaps more likely to be T. williamsoni than T. kanchil. There is a chevrotain specimen from Thateng on the Bolaven plateau (FMNH 38012) confirmed as T. kanchil (E. Meijaard pers. comm. 2008), suggesting occurrence at 800–1,200 m asl, although a short-distance trade origin may be possible. A recent finding of the genus being common in one part of Nakai–Nam Theun NPA (Johnson and Johnston 2007) gives no information on altitude of the records, and there are too few relevant specimens to allow a firm prediction as to which species they relate. Good populations certainly occur well above 600 m asl in Thailand: chevrotains are common in the degraded and edge habitats around Khao Yai National Park headquarters at 760–800 m asl (J. W. Duckworth pers. comm. 2008) and a number of specimens from nearby Pakchong suggest that these are likely to be T. kanchil, rather than unsuspected southerly occurrence of T. williamsoni. Also in Thailand, at Phu Khieo Wildlife Sanctuary chevrotains were camera-trapped commonly at 700–900 m asl, although the species involved is/are unclear (Lynam et al. 2001; A.J. Lynam pers. comm. 2008).
Lesser Chevrotains visit saltlicks regularly (Matsubayashi et al. 2007).
Lesser Chevrotain is often stated to be nocturnal, but in fact most activity is diurnal (in the first few and last few hours of daylight), with animals spending most of the night resting (Matsubayashi et al. 2003; Matsubayashi and Sukor 2005). It is highly solitary (Matsubayashi et al. 2006). Apparent territorial behaviour has been observed (Davison 1980); home ranges and core areas overlap considerably between males and females but core areas are completely separate between individuals of the same sex (Matsubayashi et al. 2006). Males are highly philopatric but females establish new home ranges when giving birth (Ahmad 1994 in Meijaard et al. 2005). Matsubayashi et al. (2003) estimated home-range size for females at 4.3 ha and for males 5.9 ha using the minimum convex polygon method, but the difference between males and females was not significant. The mean daily distance travelled for males was 519 ± 89 m, that for females 574 ± 220 m. The Lesser Chevrotain is partly frugivorous, but also eats substantial quantities of shoots and young leaves, mostly of fast-growing gap species rather than closed forest understory species; the latter tend to be richer in secondary protective compounds (Dang Huy Huynh 1968; Medway 1983; Kuznetzov and Puzachenko 1992; Matsubayashi et al. 2003). Among fruits, those of mass 1–5 g and seeds of mass 0.01–0.5 g are particularly taken (Heydon and Bulloh 1997). It seems to be facultively monogamous–polygymous (given the congruence between core areas of individual males and females with a conspecific of the opposite sex; Matsubayashi et al. 2006), with post-partum oestrus, females being almost continuously pregnant (Cadigan 1972 in Meijaard et al. 2005). The gestation period is 140–177 days (Lekagul and McNeely 1977), with 2–3 young per year, the fawns kept hidden (Meijaard et al. 2005).
nting and habitat loss occur at high levels almost throughout this species' range. While it is clear that the genus remains widespread and common in its Sundaic range in the face of these threats, few data to support assessment specifically of Lesser Chevrotain’s current status were traced: many key studies there have not identified chevrotains to species. In the non-Sundaic areas, evaluation of resilience is hampered by evident heterogeneity of chevrotain occurrence with a lack of convergence of opinion as to explanations of same.
North of the sympatry with T. napu, T kanchil is heavily hunted and is often considered one of the most preferred wild meats (Srikosmatara et al. 1992; Duckworth et al. 1999; Kuznetzov and Borissenko 2004; R. Steinmetz pers. comm. 2006, R.J. Timmins pers. comm. 2008). Nonetheless, it is clear that T. kanchil is adept at surviving in areas (at least in the lowland plains) in the face of very heavy hunting, major habitat degradation and isolation from other forest areas. Exemplifying this, it was one of the few mammals larger than a rat confirmed to persist at Houay Nhang, an isolate of a few km² of highly degraded forest just outside the capital of Vientiane facing, in the early 1990s, exceedingly concentrated hunting with guns and snares (Duckworth et al. 1994). A little to the west it persists in Sangthong district, which was heavily logged just before a 1996 survey and also supported heavy hunting (Duckworth 1996). These two areas are within 10 and 70 km, respectively, of, and ecologically contiguous with, Thangon, from where Osgood (1932) reported specimens of T. kanchil (confirmed by E. Meijaard pers. comm. 2008 as this species), and thus the modern records probably do relate to T. kanchil. Hansel (2004) provided a further record from the adjacent low hills. Numbers of chevrotains in Vientiane markets in the early 1990s (Srikosamatara et al. 1992) were so high that they could not be at the brink of extinction in this degraded and fragmented landscape. Chevrotains are still common in trade in the city, although mostly in transit rather than on open sale in the city’s markets, and their origin is not clear (T. Hansel pers. comm. 2008). The genus was recently camera-trapped quite commonly in a part of Nakai–Nam Theun NPA where ground mammals were much depleted (Johnson and Johnston 2007), perhaps indicating higher resilience than many other mammals, although there is no information to compare with pre-exploitation levels.
While non-Sundaic chevrotains can, therefore, clearly persist under extreme pressures in at least some circumstances, this does not rule out that densities might be quickly reduced through the twin pressures of hunting and habitat degradation. Decreasing population densities between the 1970s and 1990s, in at least parts of southern Viet Nam, were suggested by both spot-lighting surveys and qualitative assessments of footprints. Near Buon Luoi in December 1978, chevrotains were spotlit at about three animals per 5 km of transect route, but by 1993, when forest had undergone heavy degradation and hunting was very heavy, chevrotains were not even found every night with at least 10 km of transect (Kuznetzov and Borissenko 2004). Kuznetzov and Borissenko (2004) proposed that night-time hunting may explain chevrotain’s near-absence from habitats with open-understory (this feature allowing chevrotains to be readily hunted using spotlights and guns) in the Buon Luoi area, because by contrast in Cat Tien National Park, where the use of firearms has been banned for decades and enforcement is fairly effective, chevrotains are encountered with comparable frequency both in thickets and on exposed forest floor (Borissenko and Ivanova 2003). This sighting rates contrast is consistent with a difference between the headquarters area of Khao Yai National Park, Thailand (where chevrotains are readily found by spotlight) and which is relatively well-protected from hunting, and Lao forests (see above) where hunting was effectively unrestrained (J.W. Duckworth pers. comm. 2008). However, a proposal that, where hunting is unrestrained, as it is in most of Viet Nam and Lao PDR, chevrotains would be common in heavy forest but have been effectively eradicated from such habitat, is flawed for at least Lao PDR, where numbers of forest mammals killed through spotlight hunting are probably insignificant compared with those trapped (including with snares) and perhaps even killed using dogs (J.W. Duckworth and R.J. Timmins pers. comm. 2008, based on numbers of active hunters encountered at nigh versus traps found, in many areas of Lao PDR). Kuznetzov and Borissenko (2004) based their reasoning on only two sites and it is possible that other factors explain the differences. In sum, the effects of hunting and habitat modification, and the interaction between them, on non-Sundaic chevrotains remain most unclear.
The effects of potential threats operating in the Sundaic range are not understood well, either. Lesser Oriental Chevrotain is now rather rare on Singapore (K. Lim pers. comm. 2008), presumably nowadays constrained by habitat quality rather than by ongoing hunting, although the role of free-ranging dogs, if any, in restraining population numbers is unclear. However, the ‘island within an island’ situation of remaining forest on Singapore and the extreme habitat loss over the last 150 years prevent useful extrapolation of this species' situation there to other Sundaic areas. Poaching pressure in Kerinci-Seblat National Park, Sumatra, among snared ungulates was greatest for muntjacs and lowest for chevrotains, as assessed by diameter of the cable (Linkie et al. 2003). Chevrotains were more then nine times as abundant in areas of Bukit Barisan Selatan National Park, Sumatra, with low than with high human population density within 10 km of the park boundary, suggesting low resilience to human presence, presumably the effects of hunting (O'Brien et al. 2003); note that it is not confirmed that this information refers to T. kanchil. Bennett et al. (2000) profiled the effects of hunting in both Bornean states of Malaysia (Sarawak and Sabah), each with eight study areas, upon chevrotains (not distinguished to species) through a lengthy hunting study in February 1993 to June 1995. They constituted 8–9% of animals killed. No direct or index measure of chevrotain densities was possible at these sites to determine what effects, if any, such heavy hunting was having on chevrotains. Chevrotains are among the most favoured wild meat by inhabitants of the Sarawak Planted Forests area, Bintulu, Sarawak, after Sambar Rusa unicolor and wild pigsSus (Belden Giman pers. comm. 2008). Logging can apparently drive substantial reductions in density, at least locally, although other studies have found it allows an increase in numbers (see Habitat and ecology). No information on the use of plantation landscapes has been traced. In the Greater Sundas, lowland forest is being converted at unprecedented high rates. At least in Borneo, where this species is concentrated in areas below 100 m asl, most of its habitat either has been substantially modified during the last two decades or will be in the next two (e.g. Holmes 2000; BirdLife International 2001; Jepson et al. 2001; McMorrow and Talip 2001; Lambert and Collar 2002; Fuller et al. 2003; Kinnaird et al. 2003; Curran et al. 2004; Fuller 2004; Eames et al. 2005, Aratrakorn et al. 2006). However, inferring proportionately large population losses in Lesser Chevrotain populations is not possible: depending on how serious hunting is and what exactly is being done to the habitat post-logging (forest regeneration, tree plantation or non-woody habitat) in any given area, chevrotain numbers might remain broadly unaffected, decrease or increase in logged-over areas.
The lesser mouse deer appears to be more abundant in Sabangau than the Greater Mouse-deer, and we have identified it in 48 photos. There is strong evidence that this species is tolerant of disturbance, ranging from primary (undisturbed) forests to immature secondary forests. In Sabangau, it is frequently seen near the forest edge. Although wide-spread, there is debate as to whether it should be of higher conservation concern, as it is apparently restricted to the extreme lowlands in Borneo, in which forest loss is most rapid.