Effects of hoarding activity of Apodemus mice on the regeneration and spreading of acorn-producing tree species.

为了阐明姬鼠的贮藏行为对橡实树种更新和扩散的影响，我研究了姬鼠的种群动态和贮藏行为，Pasania edulis橡实产量，以及橡实生产到幼苗建立的死亡率。美丽银纹伊蚊和银色银纹伊蚊种群数量的季节变化基本一致，春季数量最多，夏秋两季数量减少，晚秋开始数量增加。冬季留居鼠数量的年变化与紫果杨橡子产量的年变化并不总是一致的。结果表明，紫果栎果实每3-4年发生一次肥大，在肥大年份，空果率较低。姬鼠平均能将落下的橡子搬运10- 50米，并将它们藏在土壤中。运输橡子的百分比变化的捕食强度由中型和大型哺乳动物，如野生钻孔。大约60%的橡子被囤积者找到，大约40%的橡子被囤积者以外的老鼠偷走。在这两种情况下，回收的橡子被运送到离母树更远的地方。我制作了1995年至2008年生产的橡子生命表，并进行了关键因素分析。橡子的总死亡率的年度变化期间橡子生产的树木幼苗建立（总K）由捕食的强度下降橡子由姬鼠（K21）。全K和K_（21）与密度呈负相关。在这14年中，只有在1999年、2003年和2007年这三个老鼠数量较少的年份，姬鼠才能充当种子传播者，促进橡子生产树种的再生和传播，而在另外11年，老鼠似乎充当种子捕食者。

To clarify the effects of the hoarding activity of Apodemus mice on the regeneration and spreading of acorn-producing tree species, I studied the population dynamics and hoarding behavior of Apodemus mice, the acorn production of Pasania edulis, and its mortalities from acorn-production to seedling-establishment. A.speciosus and A.argenteus showed the same seasonal changes in their numbers every year ; the population was largest in spring, decreased during summer and fall, and then increased from late fall. The annual changes in the number of resident mice during winter and the acorn production of P.edulis did not always correspond. The masting of P.edulis acorns was recorded every 3-4 years, and in the mast years, the percentage of empty acorns was low. Apodemus mice transported dropped acorns 10-50m, on average, and hoarded them in the soil. The percentage of the transported acorns varied with the intensity of predation by middle- and large-sized mammals such as wild bores. About 60% of cached acorns were recovered by their hoarders and about 40% of them were stolen by mice other than the hoarders. In both cases, the recovered acorns were transported farther from their mother trees. I made the life tables of the acorns produced from 1995 to 2008, and conducted a key-factor analysis. The annual changes in the total mortality of acorns during the period from acorn-production on the trees to seedling-establishment (Total K) was determined by the intensity of the predation of dropped acorn by Apodemus mice (k21). The density relationships of Total K and k21 were inversely-density dependent. Out of the 14 years, Apodemus mice could act as seed-dispersers and contribute to the regeneration and spreading of acorn-producing tree species only in three mast years with a low mice population ; 1999, 2003, and 2007, and in the other 11 years, mice seemed to act as seed-predators.