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Sus barbatus
Jayasilan Mohd-Azlan1*, Melynda Cheok Ka Yi1, Thaqifah Syaza Jailan1and Yong Min Pui2
1Department of Zoology, Faculty of Resource Science and Technology, Universiti Malaysia Sarawak, 94300 Kota Samarahan, Sarawak, Malaysia
2Institute of Biodiversity and Environmental Conservation, Universiti Malaysia Sarawak, 94300 Kota Samarahan, Sarawak, Malaysia
corresponding author email:
The bearded pig (Sus barbatus) is distributed from the Malay Peninsular, Sumatra, Borneo and
the southwestern Philippines (Corbett & Hill, 1992; Oliver, 1995). In Borneo they can be found in
coastal lowlands comprising peat swamp and dipterocarp forest with undulating hills and the
mountain highlands (Payne et al., 1985). The bearded pig is an omnivorous animal that forages
mainly on seeds of Dipterocarpaceae, Fagaceae, fruits, roots and invertebrates (Davis & Payne,
1982; Payne et al., 1985; Caldecott, 1988). This generalist species is known to utilize a wide
variety of habitat types but lives in one location in a stable group for the majority part of the year
(Navennec et al., 2016).
The bearded pig has been reported to be mobile and exhibit a variety of aggregation strategies,
ranging from solitary and sedentary to mass aggregation with wide ranging migration (Meijaard,
2003; Hancock et al., 2006). The shortage of food resources may force pigs to migrate.
Migrations of bearded pig have been reported in Borneo in response to mass fruiting occurrences
in Borneo (Caldecott & Caldecott, 1985; Hancock et al., 2005; Wong et al., 2005). The mast
fruiting events increases population numbers explosively and the pigs are known to migrate
across large areas to feed on the oil rich Dipterocarp seeds (Hancock et al., 2005).
The bearded pig is the most sought after wild meat by the non-Muslim natives in Sarawak where
it plays significant role socioeconomically especially in sustaining local livelihoods. In Sarawak the
bearded pig is not protected outside National Parks, Nature Reserves and Wildlife Sanctuaries.
As a non-protected species, it can be hunted for local consumption. However commercial sale of
bearded pig in Sarawak is prohibited according to Wildlife Protection Ordinance 1998 where
offenders are liable for a fine up to 5000 Ringgit (USD$1250) while the buyers can be fined up to
2000 Ringgit (USD$500). Additionally if a native is found in his possession with more than five
kilograms of wild meat for his own consumption he will be deemed to have the intention to sell or
offer for sale and can be charged up to 5000 Ringgit.
Study site
A rapid survey was carried out in Rajang River area from Kapit town to Pelagus National Park.
Rajang River (also known as Batang Rejang) is the longest river in Malaysia and the largest river
between Sabah and Sarawak, which originates from central highlands of Borneo. The Rajang
headwaters drain the northern slopes of the Kapuas Hulu Range and western slopes of Hose and
Iran mountains while the watershed of Rajang River drains the districts of Kapit, Belaga, Song,
Kanowit, Julau, Sibu, Matu, Daro, Bintangor and Sarikei (Parenti & Lim, 2005). Rajang River
drainage basin is about 50,000 km2in area with elevations exceeding 2,000 m (Parenti & Lim,
2005; Staub & Gastaldo, 2012). From a 30 years rainfall data calculation, the typical single-month
discharge rates for the Rajang River drainage basin range from about 1,000 to 6,000 m3/s, and
the average monthly discharge rate is about 3,600 m3/s (Staub et al., 2000). Peak discharge rates
during the northeast monsoon (December to March) can exceed 25,000 m3/s. There are several
rapids with strong current distributed near the headwaters (Figure 1). This river is used as the
major mode of transportation to the central regions of Sarawak. The river is busy during the
mornings and in the afternoons where express and long boats frequently shuttles people. The
riverbank along this stretch is dominated by secondary lowland dipterocarp forest, patches of
small-scale agricultural farms (e.g. pepper, rubber and paddy rice), settlements (longhouses,
school and abandoned resort), log ponds and a coal mining area. Most of the secondary forests
in this area have been logged several times except for Pelagus National Park which is situated in
the west side of the river.
Rapid boat survey was carried out from 18th – 21st of February 2016 along the Rajang River from
Kapit (N 02˚00’59.4” E 112˚56’25.7”) to Pelagus National Park that stretches approximately 32
km. At any one time there were at least two surveyors in the boat. During this survey we checked
for any bearded pig crossing the Rajang River. We also counted the number of boats and
interviewed local people involved in this hunting activity from the boats (n=20) and elders from the
longhouses (n=15).
The bearded pigs have been reported to cross the river consistently for the past two weeks. This
event occurred for approximately three weeks starting from the beginning of February 2016.
Approximately 50 % of the hunters interviewed suggest that such migrations occur right after the
young piglets were mature enough to swim across rivers for food and this can sometimes last up
to two months. The pigs were crossing from west to east across the river consistently in one
direction especially during early mornings and late evenings when there are fewer boats using the
river. This is consistent with most of the previous river crossings reported by Meijaard (2003).
However it is not known if the pigs have been crossing the river at night. In most cases the pigs
Fig 1. The fast flowing rapids of
Rajang River near the headwaters
close to Pelagus National Park at
Kaki Wong area.
were reported to cross from one to two dozens and occasionally adult females with several
juveniles. These pigs do not appear to be in the stages of emaciation and starvation as reported
by Wong et al. (2005), which suggests that famine or prolonged scarcity of food resources may
not be the driving factor in this migration.
During this rapid survey
we counted appro-
ximately 90 long boats
at any one time at 25 to
30 locations along the
riverbank waiting for
pigs to cross the river
(Figure 2). Each boat
had two to three
individuals looking out
for pigs (Figure 3). This
translates to at least 180
individuals from
approximately 200
villages at any one time
along this 32 km stretch.
Hunting using shotguns
is not allowed. Local
people who are caught
using guns will be asked
by other fellow hunters
from the nearby boats to
leave the area. The pigs
were attacked and killed
using homemade spears
(locally known as
Jerepanq and Sanqkuh:
Figure 4) and machetes.
Once the pigs are
spotted crossing far
enough from the
riverbanks, the boats will
rush towards the pigs
and the first boat to
arrive normally kills at
least one pig at a time. In
general most boats will
hunt at least one pig per
day but boats waiting at
more strategic location
often take two to three
Fig. 2. Location of boats waiting along the Rajang River during the pigs’ migration.
Fig. 3. Longboats with two to three individual waiting near the edge waiting to ambush the migrating
pigs in Rajang River in February 2016.
individuals in a day (Figure 5). The number of
hunters in each boat also partly influences the total
kill per day. A single hunter may only kill and collect
as much as two individuals per day whereas boats
with more hunters will collect as many as they can
fill their boat with. The hunters will wait from
morning until late evening, with their boats parked in
parallel to the pigs’ crossing direction to minimize
the detection of their presence. These hunters are
also opportunistic, as they kill almost all the pig
crossing. As soon as a pig is captured, it is tied to a
big plastic gallon bottle (to keep the pig afloat) while
the hunters move on to the next target and the
process continues until there are no more pigs left
for the session. Occasionally juvenile pigs are
reared if they are captured alive. Excess meat will
be preserved through fermenting and smoking the
meat. During this hunting period, if one hunting
group (per boat) takes home at least one pig per
day, then a modest estimate of pigs harvested
during this migration session at this particular river
stretch in Sarawak for a minimum of 14 days is
estimated at least 1260 pigs. With an approximation
of 30 kilograms of wild meat obtained from each pig
on this basis, this would result in an overall catch
value of 756,000 Ringgit (USD$190,000).
The rapids, wide river crossing, boats and hunting
threats did not prevent the bearded pigs from
crossing the river suggesting that the instinct to
seek new foraging grounds have superseded these
challenges. Preventing the bearded pigs from
will disable
them to find
alternative food and cause starvation, which in turn may
negatively impact local communities that depend on this
resource. The dependency of pigs on mast fruiting
suggests that the Bornean populations are delicate and
susceptible to continuous local extinctions from human
perturbation (Wong et al., 2005). Therefore local
enforcement agency must work together with local
communities to regulate hunting activities to ensure local
populations of bearded pigs are not exterminated.
Fig. 4. Weapons used for pig hunting during river crossings
(left: Jerepanq, right: Sanqkuh). The spears are about 2 meters
long, with sharp ends. The hunters usually spear the forearms
or hind legs of the pigs, just enough to immobilize them but not
killing them, thus allowing them to stay afloat.
Fig. 5. Juvenile bearded pigs hunted from a long boat
showing spear marks near the neck. Note the lateral black
brown stripes on the abdomen indicating that these
individuals are less than 6 months old.
The authors would like to thank local communities that made this brief study possible. We also
thank Department of Zoology, Faculty of Resource Science and Technology, Universiti Malaysia
Sarawak (UNIMAS), the Institute of Biodiversity and Environmental Conservation for supporting
our research, which funded by the Sarawak Energy (grants no [GL(F07)SEB/2014/03(04)] &
FRGS/STWN10(04)/990/2013(31)). We are grateful to the Sarawak Forestry Department and
Sarawak Forestry Corporation for permission to work in Central Sarawak.
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... Additionally, the time commitments related to urban jobs and (e.g. Banks, 1949;Mohd-Azlan et al., 2016). Artwork by Amy Koehler and used with permission KDM community but also the hunting relationship that has connected people and pigs across Borneo for millennia (Medway, 1964). ...
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Aim The environments that existed in south-east Asian islands during the last glacial are poorly known, limiting our understanding of mammalian biogeography in the region. The objective of this research is to investigate the ecological characteristics of mammal faunas on small islands, and to see whether the habitat requirements of the species in those faunas can be used to deduct the vegetation types that existed on islands before becoming isolated by rising sea levels. Location The maps presented here cover the small islands of tropical south-east Asia, including the Burmese, Thai and Cambodian islands in the north, the islands off the coast of west Sumatra in the west, the islands around Java in the south, and the islands off the east coast of Borneo in the east, including the Philippine islands of Palawan and those in the Sulu Archipelago. Methods The presence records of mammal species on 215 small islands in the region were compiled, and the habitat requirements for each of these species was assessed (species that had probably been introduced by humans were excluded from the analysis). For each island location (longitude and latitude), maximum altitude of the island, total area, depth to nearest land, distance to nearest island, and distance to nearest mainland were assessed. Geographical and statistical analyses were used to investigate patterns of mammalian habitat requirements. Results The geographical analysis showed that forest-dependent species, i.e. species that are only found in primary forest (lowland and mountainous), appear to be concentrated on islands off west Sumatra, in the Lingga and Riau Archipelagos, around Palawan, and around Bunguran Island; they are absent mostly from the islands of the Java Sea, those off the east coast of eastern Borneo, from most islands in the Sunda Strait, several islands in the northern South China Sea, and from all islands off the west coast of the Malay/Thai Peninsula and in the Gulf of Thailand. Species that generally occur outside primary forest, that is those in secondary forest, gardens, plantations and open areas mostly occurred on islands where the forest-dependent species were absent. The statistical analysis showed that latitude and size of islands were important factors that determined the absence and presence of forest-dependent species on small islands. Main conclusions The data suggest that during the last glacial there were several areas in the Sundaic region that remained forest covered: west of Sumatra, north-west of Borneo, the Malacca Straits and around Palawan. Other areas may have been covered by more open vegetation types like tree savanna, or open deciduous forest: on and to the east of the Malay/Thai Peninsula, the Java Sea area, including the Sunda Strait, and eastern Borneo.