同域分布啮齿动物间的不对称盗食行为研究

Food pilferage between sympatric small rodents is often asymmetrical: the predominant species can pilfer foods from the subordinate species, but it rarely happens in inverse. Within the asymmetrical pilferage interspecific relationships, what strategies of pilferage avoidance adopted by the victims is very important to their survival and to species coexistence, therefore, depends on pilferage and pilferage avoidance strategies. However, less is known about the asymmetrical pilferage between sympatric rodents. Here, we will study pilferage relationships between Korean field mice (Apodemus peninsulae, both scatter and larder hoarders, nocturnal, 20-35 g body mass), Chinese white-bellied rats (Niviventer confucianus, larder hoarder only, nocturnal, 45-150 g body mass), and Père David's rock squirrels (Sciurotamias davidianus, predominant scatter hoarder, diurnal, 180-260 g body mass) using video traps in semi-natural enclosures and in the wild in Donglingshan area, northwestern Beijing city. The study species are common in the study area, share similar habitats and food items, but vary in activity rhythm, body size and food hoarding behaviors, allowing us to hypothesize that the pilferages between them are asymmetrical. We will study the details of the asymmetrical pilferages among these species, and test the food abundance hypothesis, predominant status hypothesis, and niche overlap hypothesis to identify the effects of food abundance, interspecific predominant status, and interspecific niche overlap on asymmetrical pilferage between these rodent species.The expected results of these studies elucidate the role of interspecific relationships and coexistence between sympatric small rodents with respect to food pilferage, and provide more information to know the ecological based managements in pest rodents in the study area.

种间盗食是动物贮食损失的重要原因，同域分布啮齿动物间的盗食常是不对称的，即一种动物能盗食另一种动物的食物，但相反却难以实现，不对称盗食关系中，竞争弱势种类的反盗食策略对其本身生存和种间共存尤为重要，但种间不对称盗食行为研究鲜有报道。本项目拟通过控制性围栏实验和野外观察，利用视频监控和行为分析系统等手段，研究东灵山地区优势鼠种社鼠、朝鲜姬鼠、岩松鼠间的不对称盗食关系及其对共存的意义，尤其关注竞争弱势种类的反盗食行为，并探讨食物资源压力、优势地位、生态位重叠度对种间不对称盗食行为的影响，提出并验证资源压力假说、优势地位假说和生态位重叠度假说。在群落水平上研究种间不对称盗食关系，并提出相应新假说，具有一定创新性和理论高度。预期结果对深入认识同域分布啮齿动物间基于盗食、反盗食关系的共存机制、充实种间盗食行为研究不足、丰富贮食行为理论、为生态健康型鼠害防控积累基础资料等方面具有一定的理论和实践意义。

种间盗食是动物贮食损失的重要原因，同域分布鼠类间的盗食和反盗食常是不对称的，即一种动物能盗食另一种动物的食物，但相反却难以实现或盗食率很低。本项目通过控制性围栏实验和野外观察等方法，研究了东灵山地区岩松鼠、社鼠、朝鲜姬鼠、大仓鼠等鼠种间的不对称盗食关系及其受食物资源量、优势地位、生态位重叠度的影响。发现（1）社鼠、朝鲜姬鼠间存在不对称盗食，社鼠能盗食朝鲜姬鼠分散贮藏的食物，朝鲜姬鼠却不能盗食社鼠集中贮藏的种子，将分散贮藏转变为集中贮藏是朝鲜姬鼠应对社鼠盗食的重要策略；（2）优势地位（体重）、贮食习性影响种间盗食和反盗食行为：集中贮食的社鼠、大仓鼠的贮食强度受其它种类的影响较小；分散贮食的朝鲜姬鼠，同种个体使其贮藏量增加、将分散贮藏变为集中贮藏，个体较大的大仓鼠、社鼠使其贮藏量减少，个体较大但白天活动的岩松鼠使其分散贮藏量降低；分散贮食的岩松鼠，同种个体使其贮食量增加，花鼠使其贮食量减少，夜间活动的大仓鼠使其分散贮藏量增加；（3）种内种间盗食强度受食物资源量调节：岩松鼠贮食过程中，盗食损失率与盗食获取率基本平衡，支持互惠盗食假说，但当食物资源较丰富时，岩松鼠倾向于从食物源获取资源，而不是盗食其个体的食物；资源丰富时，社鼠倾向于从环境中获取食物，而不是盗食朝鲜姬鼠的食物，二者间的不对称盗食会减弱；（4）朝鲜姬鼠、社鼠在微生境选择、食物组成、种子选择、贮藏和搜寻、日活动节律等方面有较大重叠，使其在食物贮藏和后期食物竞争中具有较强的盗食和反盗食关系。这些结果说明同域分布鼠种间的盗食和反盗食行为具有不对称性，并受优势地位、食物资源量及生态位重叠度等因素调节。随后将关注同域分布鼠种间基于盗食与反盗食关系的互作关系及其生态效应，以探讨物种共存机制。