Melursus Ursinus Sloth Bear Vulnerable
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Melursus ursinus Sloth Bear Vulnerable Geographic Range Information Sloth bears are present in India, Nepal, Sri Lanka, and Bhutan. Until recently they were also known to occur in Bangladesh, but their continued existence there is uncertain: the last documented records are from the late 1990s. In historic times, sloth bears never ranged further west than Gujarat, India, and probably no further east than the states of northeastern India, although some unverified reports suggested that they once occurred in the southwestern corner of present day Myanmar (Erdbrink 1953). Although still widely present in its former range, its distribution is now highly fragmented. Range Countries Bangladesh (possibly extinct) Bhutan India Nepal Sri Lanka 2 Population Information A mark-resight based population estimate is available for one park in Nepal; density was estimated at 27 bears/100km2 for the whole park, and as high as 72 bears /100km2 in a core area (Garshelis et al. 1999a). Other population estimates (guesstimates) exist for 3 many other parks and reserves, but these were based on uncertain methodology (mainly just expert opinion gleaned from interviews and questionnaires). Good information is available on area of occupied range in India (Chauhan 2006, Yoganand et al. 2006), Nepal (Garshelis et al. 1999a), and Sri Lanka (Ratnayeke et al. 2006). Some attempts have been made to apply estimated densities in various protected areas to occupied area to obtain a rangewide population estimate. Depending on methods and data employed in this process, rangewide estimates vary from <10,000 to somewhat >20,000 (Garshelis et al. 1999b, Chauhan 2006, Yoganand et al. 2006). None of these estimates are considered reliable enough to track changes in population size. Habitat and Ecology Information Sloth bears subsist primarily on termites, ants, and fruits. This is the only species of bear adapted specifically for myrmecophagy (ant and termite-eating; Garshelis et al. 1999b, Sacco and Van Valkenburgh 2004). The ratio of insects to fruits in the diet varies seasonally and geographically (Baskaran et al. 1997, Joshi et al. 1997, Bargali et al. 2004, Sreekumar and Balakrishnan 2002). Sloth bears occupy a wide range of habitats on the Indian mainland including wet or dry tropical forests, savannas, scrublands, and grasslands (Joshi et al. 1995, Sreekumar and Balakrishnan 2002, Akhtar et al. 2004, Ratnayeke et al. in press). They are primarily a lowland species. Most sloth bear range in India and Nepal is limited to habitats below 1500m, although the species may occur as high as 2000m in the forests of the Western Ghats (Johnsingh 2003). In Sri Lanka, sloth bears are confined to the remaining dry forests in the north and eastern parts of the island, mostly below 300m (Ratnayeke et al. 2006). In areas where cover is sparse, and where daytime temperatures are high (a large part of the range), the bear is largely nocturnal or crepuscular and will shelter in rock outcrops, thickets, and tree cavities during the heat of the day. Although sloth bears may be active during the day in protected areas, they tend to be almost exclusively nocturnal in disturbed and fragmented forests interspersed with human habitations (Akhtar et al. 2004). Studies in Nepal and Sri Lanka suggest that sloth bears avoid areas where human disturbance is high, so crop depredation by sloth bears is typically rare (Joshi et al. 1995, Ratnayeke et al. in press). Conversely, in some parts of India, sloth bears routinely raid peanut, maize, and fruit crops (e,g., Chhangani 2002). Chauhan (2006) suggests that such crop depredations may occur because these habitats are severely affected by human exploitation, including the extraction of several food sources for bears. Sloth bears typically breed during June-July, and females give birth, usually to one or two cubs, during November –January (Laurie and Seidensticker 1977, Joshi et al. 1999, Chauhan et al. 2003). Cubs typically ride on the mother’s back during their first nine months, presumably to reduce the risk of predation. Cubs remain with their mothers for 1.5–2.5 years. 4 Threat Information Major threats to this species are habitat loss and poaching (Johnsingh 2003, Chauhan 2006). Habitat has been lost, degraded, and fragmented by overharvest of forest products (timber, fuelwood, fodder, fruits, honey), establishment of monoculture plantations (e.g., teak, eucalyptus), settlement of refugees, and expansion of agricultural areas, human settlements, and roads (Santiapillai and Santiapillai 1990). Poaching, mainly for the commercial trade in bear parts, has been reported (Servheen 1990, Garshelis et al. 1999b), but its current extent and impact on bear populations is uncertain. Poaching also occurs for local use (e.g., male reproductive organs used as aphrodisiac; bones, teeth and claws used to ward off evil spirits; bear fat used for native medicine and hair regeneration; Santiapillai and Santiapillai 1990, Chauhan 2006). Capture of live cubs for use as "dancing bears" remains a significant threat in some parts of the range (Seshamani and Satyanarayan 1997). Also, in some parts of the range, encounters between people and sloth bears have led to numerous human injuries and many deaths (Rajpurohit and Krausman 2000, Bargali et al. 2005, Chauhan 2006). Such incidents tend to occur where people frequently use bear habitat, and where the habitat has thus become severely degraded. Bears that attack or threaten to attack people may be destroyed. The only natural threats to sloth bears are tigers (Panthera tigris) and possibly leopards (P. pardus). In fact, the threat of tiger predation may account for the very aggressive nature of sloth bears (Joshi et al. 1999). Sloth bears have been observed fending off approaches by tigers, but they have also occasionally been observed as a prey item of tigers (e.g., Gopal 1991). Conservation Measures Sloth bears are reported to exist in 174 Protected Areas in India, which include 46 National Parks and 128 Wildlife Sanctuaries (Chauhan 2006). Populations appear to be reasonably well protected inside these PAs, but faced with deteriorating habitat conditions outside PAs (Santiapillai and Santiapillai 1990, Akhtar et al. 2006). Reduced cover and food resources outside PAs (Akhtar et al. 2004) have led to increased bear– human conflicts, including frequent maulings (Bargali et al. 2005). It is estimated that half to two-thirds of the sloth bears in India live outside PAs. About half the occupied range in Sri Lanka is outside PAs (Ratnayeke et al. 2006). Sloth bears are listed in Appendix I of CITES and are completely protected under Schedule I of the Indian Wildlife Protection Act. They are also protected to varying degrees by national laws in the other range countries. However, they can be killed to protect life or property. Given the aggressive nature of this animal, and the increasing number of encounters between bears and people, these bears are widely feared. Although education may help to reduce bear-human conflicts and enhance a conservation ethic among locals, the root of the problem is largely related to deteriorating habitat, which increases the chance of interaction between people and bears. Thus, habitat 5 improvements (government or community-based reforestation) would be helpful in alleviating such conflicts. Red List Assessment Category: Vulnerable Criteria: A2cd+4cd; C1 Rationale: Although no truly reliable large-scale population estimates exist for sloth bears, best guesstimates indicate a reasonable possibility of there being ~20,000 or fewer animals, and thus <10,000 adult animals. Moreover, strong evidence of their range reduction suggests that their population has declined by 30-49% over the past 30 years largely as a result of habitat loss, and to some extent from exploitation for parts, or systematic elimination as a pest. The recent probable extirpation of sloth bears in Bangladesh highlights serious concerns over persistence of small, isolated sloth bear populations elsewhere in their range, especially in unprotected areas. They are particularly vulnerable to loss of habitat because of their reliance on lowland areas, which tend to be the places most readily used by people. Poaching and trade in sloth bears or their parts is also common in many parts of their range, including the capture and removal of cubs from the wild. Given the lack of effective measures to control the rate of habitat loss and exploitation, sloth bear populations are expected to continue declining. Assessors: Garshelis, D. L., Ratnayeke S. & Chauhan, N. P. S. Assisted with range mapping: Akhtar, N., Bargali, H., Chauhan, N.P.S., Choudhury, Islam, A., Joshi, A., Ratnayeke, S., Sarker, S., & Wijeyamohan, S. Evaluators: McLellan, B. & Garshelis, D. References Akhtar, N., H. S. Bargali, and N. P. S. Chauhan. 2004. Sloth bear habitat use in disturbed and unprotected areas of Madhya Pradesh, India. Ursus 15:203-211. Akhtar, N., H. S. Bargali, and N. P. S. Chauhan. 2006. Extent of biotic pressure on unprotected sloth bear habitat and human-bear conflict in North Balispur Forest Division. Tigerpaper 33(1):33-40. Bargali, H. S., Akhtar, N. and Chauhan, N. P. S. 2004. Feeding ecology of sloth bears in a disturbed area in central India. Ursus 15:212–217. 6 Bargali, H. S., N. Akhtar, and N. P. S. Chauhan. 2005. Characteristics of sloth bear attacks and human casualties in North Balispur Forest Division, Chhattisgarh, India. Ursus 16:263-267. Baskaran, N., N. Sivanagesan, and J. Krishnamoorthy. 1997. Food habits of the sloth bear at Mudumalai Wildlife Sanctuary, Tamil Nadu, South India. Journal of the Bombay Natural History Society 94:1-9. Chhangani, A.K. 2002. Food and feeding of sloth bear (Melursus ursinus) in Aravalli Hills of Rajasthan, India. Tigerpaper 29(2):1-6. Chauhan, N. S. 2006. The status of sloth bears in India. In: Understanding Asian bears to secure their future. pp: 26-34 Japan Bear Network, Ibaraki, Japan. Chauhan, N.P.S., Bargali, H.S.