Wendland Victor
, Ringbahnstr. 79, D-100, Berlin 42.
Oecologia. 1975 Dec;20(4):301-310. doi: 10.1007/BF00345520.
In the biggest forest of West Berlin, the Grunewald, with an area of 3100 ha, the Yellow-necked field mouse (Apodemus flavicollis) is the most abundant vertebrate. From 1952 to 1973 I collected owl pellets (9/10 of which were Tawny owl pellets) from the West Berlin area, and found in them 35041 vertebrates. During the investigation it was found that the actual percentage of Apodemus flavicollis in the total prey from the nesting Tawny olws (Strix aluco) in the Grunewald showed a noticeable peak every 3 years, fluctuating between 36.2 to 40% of the total take. In both the following years the actual percentage falls on a regular basis to approximately half (17.6 to 23.7%). Investigation of the breeding longeared owls (Asio otus) in the Grunewald gave the same picture. Only in 1973, the last year of the investigation, did a break in this regularity occur.One of the diagrams representing these 21 years of investigation (see Fig. 3) shows this out-of-the-ordinary regularity over the whole period. It is particularly noticeable that all peaks of the curve lie at nearly the same height (36-40%), and also that the actual percentage values of the low point years show only slight variation, (17.6-23.7%). One parallel study over 11 years in another West-Berlin forest area showed similar results.From these results it can be concluded that the regulation of population size of the Yellownecked field mouse pass through a rhythmical 3-year cycle which is affected neither by the weather (climate) nor by food availability, but is definitely regulated by physiological intraspecific events.
在西柏林最大的森林格鲁内瓦尔德森林（面积3100公顷）中，黄颈姬鼠是数量最多的脊椎动物。1952年至1973年期间，我从西柏林地区收集了猫头鹰的食丸（其中十分之九是仓鸮的食丸），并在其中发现了35041只脊椎动物。在调查过程中发现，格鲁内瓦尔德森林中筑巢的仓鸮（Strix aluco）所捕食猎物中黄颈姬鼠的实际比例每3年有一个明显的峰值，占总捕获量的36.2%至40%。在随后的两年里，实际比例会定期降至大约一半（17.6%至23.7%）。对格鲁内瓦尔德森林中长耳鸮（Asio otus）繁殖情况的调查也呈现出相同的情况。只有在调查的最后一年1973年，这种规律出现了中断。代表这21年调查结果的一张图表（见图3）显示了整个时期这种不同寻常的规律。特别值得注意的是，曲线的所有峰值几乎处于相同高度（36 - 40%），而且低谷年份的实际百分比值变化很小（17.6% - 23.7%）。在西柏林另一个森林地区进行的为期11年的平行研究也得出了类似的结果。从这些结果可以得出结论，黄颈姬鼠种群数量的调节经历一个有节奏的3年周期，这个周期既不受天气（气候）影响，也不受食物供应影响，而是肯定由种内生理事件调节。
