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1.
西藏南迦巴瓦峰地区孟加拉虎的初步研究   总被引:4,自引:2,他引:2  
1994年5~6月、9~10月及1995年6~12月,作者对西藏东南部南迦巴瓦峰和邻近地区的孟加拉虎的分布及生态进行了野外调查,初步弄清了该地区虎的现状。通过在墨脱县格当乡的抽样调查及跟踪观察虎的移动和觅食,查明了金珠藏布江流域内近两年有关虎捕食大型牲畜的报告属实。1993年10月至1995年7月,该河谷内因虎捕食共损失牛、马和骡302头,估计活体总重量约59881kg,平均月损失2722kg,相当于自然状态下11头虎的月进食量。全乡12个村的牲畜均受到不同程度的影响,受损的户数占该乡总户数的62%,户牲畜损失率为7.7%~100%不等。对其它动物的调查表明,虎大量捕食牲畜与低海拔河谷的开发和环境中虎的自然食物缺乏有关  相似文献   
2.
1.  The larva of the tiger beetle (Cicindela chinensis) possesses six stemmata on either side of the head. Optical and physiological properties of two pairs of large stemmata and a pair of anterior medium sized stemmata, and responses of second-order visual interneurons (medulla neurons) have been examined.
2.  Objects at infinite distance were estimated to focus 50 m deep in the retina in the large stemmata. Receptive fields of four large stemmata, the acceptance angle of each being 90°, largely overlapped one another.
3.  The stemmata possessed a single type of retinular cell with a maximal spectral sensitivity at 525 nm, and a flicker fusion frequency of 25–50 Hz.
4.  Medulla neurons expanded fan-shaped dendrites in the medulla neuropil, and their axons extended into the protocerebrum. They responded to illumination with a variety of discharge patterns. They also responded with spike discharges to moving objects and to apparent movements provided by sequential illumination or extinction of LEDs. They did not show directional selectivity. They possessed well-defined receptive fields ranging from 30° to 105°.
  相似文献   
3.
黑龙江省野生东北虎调查管理信息系统的构建   总被引:1,自引:0,他引:1  
文章以黑龙江省野生东北虎(Panthera tigris altaica)野外调查数据为基础,利用地理信息系统技术、计算机技术与野生动物资源调查管理技术,构建了黑龙江省野生东北虎调查管理信息系统。主要运用面向对象程序设计语言C#和ArcGIS Engine嵌入式组件技术以及SQL Server数据库技术,设计并构建东北虎调查管理系统,实现了对野生东北虎调查数据的图形可视化操作管理。同时,结合研究区域内的自然因素和人文因素对调查资源进行动态的空间分析,及时准确地反映出东北虎的种群数量和空间变化规律,并制作出相应的分类专题图及野外分布信息统计图表等。该管理信息系统将有助于野生东北虎种群及栖息地调查数据与资料的科学管理,对于推动我国野生东北虎就地保护和科学管理具有重要意义。  相似文献   
4.
Connectivity for large mammals across human-altered landscapes results from movement by individuals that can be described via nested spatial scales as linkages (or zones or areas) with compatible land use types, constrictions that repeatedly funnel movement (as corridors) or impede it (as barriers), and the specific paths (or routes) across completely anthropogenic features (such as highways). Mitigation to facilitate animal movement through such landscapes requires similar attention to spatial scale, particularly when they involve complex topography, diverse types of human land use, and transportation infrastructure. We modeled connectivity for Asian elephant (Elephas maximus) and gaur (Bos gaurus) in the Shencottah Gap, a multiple-use region separating two tiger reserves in the Western Ghats, India. Using 840 km of surveys for animal signs within a region of 621 km2, we modeled landscape linkages via resource selection functions integrated across two spatial resolutions, and then potential dispersal corridors within these linkages using circuit theoretical models. Within these corridors, we further identified potential small-scale movement paths across a busy transportation route via least-cost paths and evaluated their viability. Both elephants and gaur avoided human-dominated habitat, resulting in broken connectivity across the Shencottah Gap. Predicted corridor locations were sensitive to analysis resolution, and corridors derived from scale-integrated habitat models correlated best with habitat quality. Less than 1% of elephant and gaur detections occurred in habitat that was poorer in quality than the lowest-quality component of the movement path across the transportation route, suggesting that connectivity will require habitat improvement. Only 28% of dispersal corridor area and 5% of movement path length overlapped with the upper 50% quantile of the landscape linkage; thus, jointly modeling these three components enabled a more nuanced evaluation of connectivity than any of them in isolation.  相似文献   
5.
Conspecific competition is an important component of the ecological processes of many species. In the case of sessile consumers, high population densities lead to competition within conspecific populations that, in turn, affect the survival, growth, and reproduction of the individuals involved. This study quantified neighborhood crowding and evaluated the extent of density effects on a tiger beetle (Cicindela japonica Thunberg) population by monitoring individually identified larvae at regular intervals. As an index of conspecific competition, the neighborhood density (the number of other larvae within a given radius for each larva) of each individual was measured. The radius size representing the highest mean coefficient of variation of density was determined as a suitable scale for detecting the density effects. Multiple logistic regression analysis was carried out to evaluate the effects of three factors (neighborhood density, prey abundance, and environmental influences) on larval survival and development. The analysis revealed that the neighborhood density significantly influenced the survival and development of larvae through every larval stage from the first to the third-instars. Moreover, the neighborhood density had a stronger influence on larvae of the same instar as compared to that on those of different instars. Our results suggest that density-dependent mortality affects the tiger beetle larvae due to the lifestyle pattern of these sedentary, ambushing predators that exhibit an aggregated spatial distribution.  相似文献   
6.
浙江丽水虎纹蛙形态特征的两性异形和食性   总被引:5,自引:0,他引:5  
林植华  计翔 《动物学研究》2005,26(3):255-262
用数显游标卡尺测量了407只2001—2003年9月下旬至10月上旬浙江丽水罚没的死亡虎纹蛙的体长等10个形态指标,结果表明:雌性成体体长(SUL)大于雄性成体,幼体形态无显著两性差异;ANCOVA去除SUL差异的影响后,雌性成体的头长和后肢长大于雄性成体,前肢长、眼径和耳径则小于雄性成体。前肢两侧对称性的偏移度成体大于幼体,雌性大于雄性;后肢两侧对称性成幼体和两性无显著差异。10个形态指标主成分分析的前三个主成分共解释64·6%的变异:第一主成分中头宽、眼径和耳径,第二主成分中后肢长,第三主成分中眼间距和鼻间距分别有较高的正负载系数。用NikonSMZ-1000解剖镜鉴别277只个体胃内容物中的食物种类,发现其秋季食物以节肢动物为主;成幼体和两性食物生态位宽度为3·42~5·25,食物生态位重叠度较高为0·93~0·98。分析表明,虎纹蛙局部形态特征的两性差异微弱,而体长两性异形差异显著;雌体具有较大的体形与食性无关,而可能与生育力选择的作用有关。  相似文献   
7.
半圈养条件下东北虎繁殖期的行为时间分配   总被引:4,自引:2,他引:2  
1998年 10月~ 2 0 0 0年 10月在黑龙江东北虎林园 ,采用随机取样法和瞬时扫描取样法对繁殖期东北虎的行为进行了研究。结果表明 ,在繁殖期的不同阶段东北虎的行为发生较大的变化。在发情交配期雌雄虎的时间分配相似 (P >0 0 5 ) ,均将最多的时间用于运动 ,用于休息的时间较少 ,用于发情交配和其它行为的时间较多。雌虎在妊娠期较多的时间用于休息和运动 ,取食、站立、社会和其它行为的时间均较少 ;产仔期最多的时间用于休息 ,其次是运动 ,用于产仔和其它行为的时间较多 ,用于取食的时间最少 ;哺乳期最多的时间用于休息 ,其次是哺乳和运动 ,用于取食和其它行为的时间较少。活动规律方面 ,各种行为在强度、出现和持续的时间上存在较大差异。单因素方差分析表明 ,在繁殖期的不同阶段雌性东北虎的休息和运动存在极显著差异 (P <0 0 0 1) ,取食存在显著差异 (P <0 0 5 ) ,只有其它行为不存在显著差异(P >0 0 5 )。 10 0日龄内幼虎用于休息的时间最多 ,其次是运动和取食 ,其它行为的时间最少。  相似文献   
8.
中国的野生东北虎(Panthera tigris altaica)数量已降到了极低的状态,及时开展有关东北虎及其猎物资源野外调查,对了解东北虎生存现状和制定保护策略都具有重大意义.吉林珲春东北虎国家级自然保护区是我国现存东北虎活动最频繁的地区之一,为了解该保护区的东北虎及其猎物资源状况,2009~2010年冬季,采用样...  相似文献   
9.
虎血清H5 亚型流感病毒抗体调查   总被引:1,自引:1,他引:1  
为查明我国圈养虎群中H5 亚型流感病毒的流行情况,应用血凝抑制(HI)方法检测了1998 ~ 2009 年间采集于哈尔滨、宜昌、桂林、唐山、上海和郑州等地的309 份虎血清样品的H5 亚型流感病毒抗体效价。结果发现1998 年4 月至2002 年4 月采集的20 份血清样品全部为H5 亚型流感病毒HI 抗体阴性。在2002 年7 月至2003
年6 月采样于上海、唐山、哈尔滨的34 只虎中,有31 只曾出现过高热、抽搐和肺炎症状,其中24 只虎的血清样品H5 亚型流感病毒HI 抗体呈阳性(抗体效价1∶ 10 ~ 1∶ 320),2 只无临床症状虎也为抗体阳性。对2004 年随机采集自哈尔滨的220 份血清样品调查发现抗体阳性率可达25.9% ,其中28 只有临床高热与肺炎病史的虎中有14 只抗体呈阳性(抗体效价1∶ 10 ~1∶ 80),其余无病史的192 只虎中有43 只抗体阳性。2009 年8 月采集的35 份血清中仅有3 份H5 阳性,抗体阳性率下降为8.6% 。上述结果表明H5 亚型流感病毒能够感染虎并对圈养虎的健康构成威胁,而且其公共卫生意义更值得关注。  相似文献   
10.
Elephants are thought to be effective seed dispersers, but research on whether elephant dung effectively protects seeds from seed predation is lacking. Quantifying rates of seed predation from elephant dung will facilitate comparisons between elephants and alternative dispersers, helping us understand the functional role of megaherbivores in ecosystems. We conducted an experiment to quantify the predation of Dillenia indica seeds from elephant dung in Buxa Reserve, India from December 2012 to April 2013. Using dung boluses from the same dung pile, we compared the number of seeds in boluses that are a) opened immediately upon detection (control boluses), b) made available only to small seed predators (<3 mm wide) for 1–4 months, and c) made available to all seed predators and secondary dispersers for 1–4 months. Using a model built on this experiment, we estimated that seed predation by small seed predators (most likely ants and termites) destroys between 82.9% and 96.4% of seeds in elephant dung between the time of defecation and the median germination date for D. indica. Exposure to larger seed predators and secondary dispersers did not lead to a significant additional reduction in the number of seeds per dung bolus. Our findings suggest that post-dispersal seed predation by small insects (<3 mm) substantially reduces but does not eliminate the success of elephants as dispersers of D. indica in a tropical moist forest habitat.  相似文献   
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