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1987年9月至1989年8月,笔者对来自云南瑞丽的2只雄性马来熊成体和7只幼体(3♂,4♀♀)在人工饲养条件下进行了观察研究,本文报道在不同生长时期的不同饲料配方、幼熊感觉器官的发育、齿式的形成、外部形态的变化、体重的生长方法及行为。  相似文献   
2.
We assessed the effectiveness of national and international wildlife trade regulations in Asia by surveying four wildlife markets in Myanmar for bears and bear parts. Bears are protected in Myanmar and neighbouring countries, and are included in CITES Appendix I, precluding international trade. Three of the four wildlife markets were situated at the border with neighbouring countries (China and Thailand) whereas the fourth, situated in Myanmar’s interior, also catered to international markets. During seven checks (1999–2006) we recorded 1,200 bear parts, representing a minimum of 215 individual bears. Most items were from Asiatic black bears Ursus thibetanus but also sun bear Helarctos malayanus parts were offered for sale. There were significant temporal and spatial differences in what items were offered for sale. Prices were low (USD 4–40 per item) and the total monetary value of the items for sale was USD 6,500–9,500 (not including gall bladders). Carcasses, skulls, canines, paws, claws, whole skins, pieces of skin, gall bladders and derivates, were openly displayed, with vendors being frank about prices, origin, and potential buyers. Only in the interior were prices quoted in the local currency; at the other three markets currencies of the neighbouring countries were used. Legal (international) trade in bears or bear parts from Myanmar is virtually non-existent, and the observed trade in bear parts strongly indicates a serious lack of enforcement effort. International trade in bear parts from Myanmar is significant, and open, and we conclude that the enforcement of wildlife trade regulations, at least when they concerns bear species, have by and large failed.  相似文献   
3.
马来熊脑源性神经营养因子基因编码区的克隆与序列分析   总被引:4,自引:0,他引:4  
参照人脑源性神经神经生长因子(BDNF)基因序列设计出一对引物,利用聚合酶链式反应,首次从马来熊基因组DNA中扩增和克隆到BDNF基因的编码区。对该基因所作的序列分析表明,马来熊和人BDNF基因编码区的核苷酸序列同源性为94%,而与大熊猫BDNF基因的核苷酸序列同源性高达99%。在推导的多肽序列中,除在前导肽区有两个氨基酸的差异外,马来熊BDNF的成熟区与人和其他已报道的哺乳动物BDNF成熟区的氨  相似文献   
4.
Wild bear populations in Southeast Asia are threatened with extinction, but the ecology and distribution of the 2 species occurring in the region's protected areas is poorly known, so there is little scientific basis underlying conservation strategies. We used bear signs, primarily claw marks on climbed trees, to study habitat selection and distribution of Asiatic black bear (Ursus thibetanus) and sun bear (Helarctos malayanus) across Khao Yai National Park, Thailand from March to December 2008. We found black bear claw marks in 24 of 30 random sample blocks (80%), indicating that this species was widely distributed across Khao Yai. Sun bear signs were much scarcer: their claw marks occurred in 11 blocks (37%); data were too sparse for sun bear so we limited our focus to Asiatic black bear. Using logistic regression, we found that fruit abundance best explained variation in presence of black bear, whereas human disturbance, distance to park edge, elevation, and ground cover had little influence. Fruits appear to be a key resource for Asiatic black bears, and factors affecting fruit abundance or shifts in seasonality (e.g., climate change) will impact bear populations. Knowledge of this relationship will allow managers to be more proactive in managing bears. We recommend using sign surveys for monitoring changes in black bear occupancy as they are inexpensive, efficient, and can be conducted by trained park rangers. © 2011 The Wildlife Society.  相似文献   
5.
Abstract: Asiatic black bears (Ursus thibetanus) and sun bears (Helarctos malayanus) are sympatric in mainland Southeast Asia and face similar threats of habitat loss and commercial poaching. They are rarely seen but leave distinct signs, especially claw marks on climbed trees. These markings, which are potentially valuable indicators of presence, population status, and behavior of black bears and sun bears, have limited usefulness if the 2 species cannot be differentiated. We measured 121 claw mark imprints on climbed trees from 43 known (mainly captive) individual black bears and sun bears of both sexes in Thailand and Cambodia. The span across the markings made by 3, 4, or 5 claws from the hind foot was significantly greater for black bears than sun bears. We developed discriminant function models with these variables and arranged them in a 3-step process that distinguished claw marks as either sun bear, black bear, or indeterminate. This procedure correctly classified 95% of claw marks from the experimental animals. Tested on wild bears (at sites where only one species occurred), the procedure correctly classified 91% of claw marks of black bears in China (n = 94) and 100% of claw marks of sun bears in Indonesia (n = 32). The main limitation of the method was in distinguishing young, small black bears (cubs and yearlings) from sun bears. Nevertheless, application of these findings will be valuable in bear research and monitoring programs throughout Southeast Asia, where sign surveys have, until now, been hampered by the inability to differentiate these 2 ecologically and behaviorally similar species. (JOURNAL OF WILDLIFE MANAGEMENT 72(3):814–821; 2008)  相似文献   
6.
Droughts and forest fires, induced by the El Niño/Southern Oscillation (ENSO) event, have increased considerably over the last decades affecting millions of hectares of rainforest. We investigated the effects of the 1997–1998 forest fires and drought, associated with an exceptionally severe ENSO event, on fruit species important in the diet of Malayan sun bears (Helarctos malayanus) in lowland dipterocarp forest, East Kalimantan, Indonesian Borneo. Densities of sun bear fruit trees (≥10 cm DBH) were reduced by ~80%, from 167±41 (SD) fruit trees ha?1 in unburned forest to 37±18 fruit trees ha?1 in burned forest. Densities of hemi-epiphytic figs, one of the main fallback resources for sun bears during periods of food scarcity, declined by 95% in burned forest. Species diversity of sun bear food trees decreased by 44% in burned forest. Drought also affected sun bear fruit trees in unburned primary forest, with elevated mortality rates for the duration of 2 years, returning to levels reported as normal in region in the third year after the ENSO event. Mortality in unburned forest near the burn-edge was higher (25±5% of trees ≥10 cm DBH dead) than in the forest interior (14±5% of trees), indicating possible edge effects. Combined effects of fire and drought in burned primary forest resulted in an overall tree mortality of 78±11% (≥10 cm DBH) 33 months after the fire event. Disturbance due to fires has resulted in a serious decline of fruit resources for sun bears and, due to the scale of fire damage, in a serious decline of prime sun bear habitat. Recovery of sun bear populations in these burned-over forests will depend on regeneration of the forest, its future species composition, and efforts to prevent subsequent fire events.  相似文献   
7.
圈养马来熊行为节律和时间分配的季节变化   总被引:1,自引:0,他引:1  
2009年3-12月,分春、夏、秋、冬4个季节,采用人工观察和红外摄像记录观察2种方式,对上海动物园的圈养马来熊进行行为学研究。建立的行为谱包括休息、走动、踱步、乞食、采食、爬树、探寻、擦痒、玩耍、追逐、嗅闻、示警、打斗、爬跨、舔阴、交配和排泄,将相关行为合并后归纳成6类,即休息、运动、乞食、刻板、社群和其他行为。马来熊用于休息的时间最多,其次是运动和乞食行为。各行为具有不同程度的季节性差异,运动行为(F=62.748,P<0.001)和社群行为(F=26.041,P<0.001)季节性差异极显著,刻板行为(F=4.667,P<0.05)差异显著,休息行为(F=1.857,P>0.05)和乞食行为(F=1.180,P>0.05)差异不显著。圈养马来熊具有明显的日活动节律,00:00-5:00和20:00-24:00是马来熊的休息高峰,6:00开始活动量增大,8:00-9:00是马来熊的正常进食高峰,同时,运动、乞食、社群等行为逐渐增多,乞食行为集中在运动场10:00-15:00游客多的时段。18:00之后运动逐渐减少,进入休息状态。春夏昼间行为比较,运动和刻板行为(P<0.05)差异显著。年龄因素,春季对休息、运动和刻板行为影响特别显著(P<0.001),社群和乞食行为的影响显著(P<0.05),夏季对乞食行为影响特别显著(P<0.001),运动、刻板和社群行为影响显著(P<0.05)。性别因素,春季对社群行为影响极显著(P<0.001),休息、乞食和其他行为影响显著(P<0.05),夏季只对社群行为影响显著(P<0.05)。秋冬间各行为差异不显著,室内和运动场的行为对比表明,刻板和休息多在室内,运动行为多在运动场,室内和运动场秋季的运动行为和社群行为差异显著(P<0.05),冬季的刻板行为差异极显著(P<0.001)。  相似文献   
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