石山生境中白头叶猴的觅食策略与空间记忆

Two major challenges that social animals face in exploiting their environment are the ability to locate ephemeral, widely scattered, and productive feeding sites and to obtain access to food resources. How can they find the feeding and resting sites? This question is the center of behavioral ecology and animal cognition. Studies of foraging and ranging behavior in several animal species indicate evidence of goal-directed travel and relatively straight-line movement between distant or out-of-view feeding sites. In general, animals may maintain detailed internal representations or "mental maps" of the spatial locations and distributions of major feeding and resting sites within their home range. Studies on the spatial memory and foraging strategy may provide the information on the cognitive ability and evolution.White-headed langurs Trachypithecus leucocephalus are listed as class I special state protected wildlife in China, as well as the Appendix II spicies in CITES. They are restricted to only four counties in southern Guangxi. Their habitat area is about 200 km2 . The population size is fewer than 700. Previous authors have reported their distribution , general ecological habits, activity budgets, diet and habitat quality, respectively . But detailed data on the relationships among spatial memory, ranging behavior and foraging strategy of white-headed langurs have not been previously available. In this study, data on distribution of resources(including food resources,feeding sites and resting sites), ranging patterns, home range size, daily travel length and the use of feeding route and landmarks will be collected to test hypotheses concerning forging stragegy and spatial memory in langurs. The results will formulate the foundation to evaluate the ability of spatial memory,which should enhance our understanding on the cognition adaption of this endangered primate. Furthermore, this study will provide foundational data to identify the priority and key area in habitat conservation.

如何准确到达觅食地点是动物生存中面对的主要挑战，也是行为生态学和动物认知研究领域的热点内容。在觅食和漫游过程中，动物的漫游线路选择与空间记忆功能有关，它们通过对家域内的主要觅食地和休息地的位置等信息进行编码，形成记忆地图。对灵长类的觅食策略及其空间记忆功能的研究，能进一步了解动物的认知能力、适应策略及其进化。白头叶猴是我国特有的一级重点保护珍稀濒危动物,栖息生境仅200km2左右，种群数量少于700只。目前，白头叶猴的觅食策略、漫游行为和空间记忆功能关系的研究尚属空白。我们从白头叶猴的觅食策略和漫游行为入手，收集食物资源、觅食地和休息地的空间分布数据，研究其家域、日活动距离、漫游规律、觅食线路选择，通过验证空间记忆模型假说，探讨白头叶猴的觅食策略与空间记忆功能的关系。本研究对深刻理解白头叶猴空间记忆功能和认知能力具有重要理论价值，同时对栖息地保护中重点和优先区域的确定具有重要实践意义。

对灵长类的觅食策略及其空间记忆的研究对深入了解动物的认知能力和食性适应策略及其进化有重要意义。本项目通过分析白头叶猴的重要食物资源、觅食地、休息地的空间分布对日活动线路的影响，探讨白头叶猴的漫游行为、觅食策略和空间记忆模式。研究表明，白头叶猴共计采食134种植物，分别隶属48科75属。猴群主要以树叶为食物，占总觅食记录比例72.2%-80.7%，其中嫩叶占55.6%-66.4%，成熟叶占14.3%-16.6%；其次为果实，占11.4%-22.8%；依次为花，占3.1%-5.8%；最后为其它部位，占1.9%-2.2%。白头叶猴并不是均匀利用食物种类。在134种食物中，占全年觅食总记录的1%以上有23种，共占76.6%；觅食比例>2%的15种，>4%的6种，>8%的仅有2种。白头叶猴采食最多的10种植物共占总觅食记录的53.2%。休息是白头叶猴主要行为类型，占日活动时间的37.7%-42.8%；其次为觅食，占24%-24.4%；依次为移动，占17.5%-19.2%；再次为社会行为，占 14.6%-17.7%，最后是其他行为，仅占0.8%-1.6%。研究猴群的家域面积为14.5-15.8ha。猴群选择性地利用家域，对重要斑块表现出集中利用的趋势，这与食物的数量成正相关。猴群对重要斑块的利用方式维持稳定。平均每天移动距离为449.6-480.7m。猴群早晨离开夜宿地—上午觅食高峰发生方格—中午休息高峰发生方格—下午觅食高峰发生方格—傍晚进入夜宿地之间有固定路线节段，平均长度为30-125m。在猴群移动线路网络中，共有20-33个重要节点，其中80%以上为重要觅食斑块。数据显示，白头叶猴的觅食线路的选择可能是基于固定线路地图，其中，重要觅食斑块空间分布对觅食路线的选择有重要影响，觅食斑块在白头叶猴的记忆模式中起到标志物的作用。我们还对同域分布的熊猴和猕猴的生态学进行了研究。