MALAYAN SUN BEARS-Sun Bear-Helarctos malayanus
The Malayan sun bear (Helarctos malayanus) is the only tropical bear species inhabiting lowland tropical forest of Bangladesh, Myanmar, Thailand, Laos, Kampuchea, Vietnam, Southern China, Peninsular Malaysia, and the islands of Sumatra and Borneo (Servheen 1990). They are the smallest of the eight living bear species, which, in combination with its long claws, is possibly an adaptation for its habit of climbing trees
for feeding and resting (Meijaard 1999a). Adults are about 120 to 150 cm long and weigh 27 to 65 kg. Males are 10 to 20 % larger than females (Sterling 1993). They have short, sleek, black coats with a more or less crescent-shape white or yellowish ventral patch. Often this ventral patch is dotted with black spots, and varies in size, shape, and color. The name of the sun bear in Thailand and Malaysian Chinese translates to “dog bear,” probably because of their small size, short hair, and smaller head that is more dog-like than those of the Asiatic black bears (Ursus thibetanus) (Servheen 1990).
Malayan Sun Bear |
live (Kemf et al. 1999).
The species was listed as protected in Peninsula Malaysia and Indonesia in 1972 and 1973, respectively (Khan 1988; Santiapillai and Santiapillai 1996). In the Malaysian state of Sabah, sun bears are listed as a totally protected animal under Wildlife Conservation Enactment 1997; hunting of this species is prohibited (Sabah Government 1997). The species receives little conservation attention in any country within its range. This lack of attention stems from the fact that the sun bear is uncommon, rarely seen, and competes for conservation attention with major species of conservation interest in its range, such as Sumatran rhinoceros (Dicerorhinus sumatrensis), tigers (Panthera tigris), Asian elephants (Elephus maximus), orangutans (Pongo pygmaeus), and several smaller primate species.
The habitats of the sun bear are the lowland tropical hardwood forests of Southeast Asia. These forests are highly diverse and are valued for timber production. Timber harvest affects portions of the habitats of the sun bear. Malaysia and Indonesia are the world’s leading exporters of tropical hardwoods, sawn-wood, and veneer (Laarman 1988), and much of this harvest originates in sun bears habitats. In Peninsula Malaysia, the proportion of the total land area under forest declined from 74 percent in 1958 to about 40 percent in 1990- a drop of 34 percent in 32 years (Aiken and Leigh 1992). Another source reported that 48 percent, about 64,000 km2 of forestlands in Peninsula Malaysia were cleared or will be developed for agriculture (Abidin et al. 1991). In Sumatra, it is estimated that between 65 and 80 percent of the lowland forest have already been lost (Whitten et al. 1984). By 1988, the remaining lowland forest had further decreased to only 10 percent of the land area of Sumatra (Santaipillai and Santiapillai 1996).
According to the World Bank, the deforestation rate in Borneo reached 7,000 km2/year in 1988 (Davis and Ackermann 1988). Other data indicated that Kalimantan, Indonesian Borneo, lost more than 100,000 km2 of forest between 1984 and 1990 (Meijaard 1999b). In Sabah, forest harvest almost tripled from 1,570 km2/year in 1980 to 4,263 km2/year in 1990 (Meijaard 1999b), and in Sarawak, forest harvest increased from 1,400 km2 to 4,500 km2/year (Rijksen and Meijaard 1999). Between 1960 and 1990, 30-60% of suitable sun bear habitat was estimated to have been reduced in Borneo (Collins et al. 1991; Meijaard 1999b; Rijksen and Meijaard 1999).
Malayan Sun Bear |
Meijaard (2001) predicted that some 14,000 – 28,000 sun bear will lose their habitat in Kalimantan, and most likely die in the next 5-10 years, due to the disappearance of suitable sun bear habitat across its distribution range, together with hunting pressures. In a report by Caldecott (1988) on hunting activities in Sarawak, sun bear were most often thought to be in rapid decline. His survey revealed that 77% of 48 longhouses (traditional communal house in Sarawak and Kalimantan) reported a serious decline in the number of Malayan sun bears. Based on the information provided by Caldecott (1988) (approximately 1 bear/50 hunting family was killed each year), Cleary and Eaton (1992) (estimated of 105,000 hunting families), Colins et al. (1991) and Meijaard (1999a) (93,000 km2 of potential sun bear habitat), and Davies and Payne
(1982) (estimated bear density of 1 bear/4 km2 ), Meijaard (1999b) estimated that 10% of the sun bear population in Sarawak was shot in 1988. Additional threats to the sun bear populations in the wild include the uses of sun bear parts for traditional ceremonies, the international and regional trade in sun bears and bear parts, and keeping sun bears as pets (Santiapillai and Santiapillai 1996; Meijaard 1999b).
Despite threats from habitat loss and hunting, Malayan sun bear remains one of the most neglected large mammal species in Southeast Asia, and the least known bear species in the world (Servheen 1999). Even basic biological attributes such as food habits, home range size, and reproductive biology are unknown. Until recently, little research had been conducted on Malayan sun bear ecology, and there have been no organized surveys of its distribution and population densities (Meijaard 1997). The lack of biological information on the sun bear is a serious limitation to conservation efforts (Servheen 1999). Basic research on sun bears is the highest priority research need for any of bear species worldwide (Servheen 1999). Because so little information exist on their biology and numbers, sun bears are classified as “Data Deficient” in the 2001 IUCN Red List of Threatened Animals (IUCN 2001).
The scarcity of biological and ecological information of Malayan sun bear can be largely attribute to the animals’ secretive behavior, low density, uncommonly seen, spear distribution, and hostile environment in which it lives. Because of its shy, secretive nature, and because it lives in dense tropical forest, it is impossible to study this species from direct observation. Thus, radio-telemetry, together with remote sensing automatic cameras, are useful tools to study its ecology. My study is one of the first successful and in-depth attempts using radio-telemetry to gather information on sun bear food habits, home range, movement patterns, activity patterns, population density, use of day beds, among other topics. This study also documented a famine period during a prolonged non-fruiting season where we observed signs of starvation among sun bears and
bearded pigs (Sus barbatus) in the forest. Field works were undertaken during the summer of 1998, and between January 1999 and December 2000.
Few important reasons that make this study plausible and successful, among others, were the permission to conduct this study approved by Economic Planning Unit of the Malaysian Federal Government, Danum Valley Management Committee, and approval and collaboration with Sabah Wildlife Department. The study would also not have been successful without the facilities, warm hospitability, and help provided by staffs from Danum Valley Field Center and Sabah Wildlife Department.
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