We studied populations of the eusocial paper wasps Polistes nimpha from 2012 to 2014, near Poznań, Poland, to identify the causes of mortality and to analyze changes in the number of active nests during the breeding season (from May to September). Results of the 3-year study showed that the major cause of P. nimpha mortality (51.9 %) in the study areas was the activity of mammals, probably foxes and wild boars. The second major cause of wasp death was ant predation (12 %). Only 11 of the 308 nests (3.6 %) demonstrated a natural colony decline, following the emergence of reproductives.

中文翻译：

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Polistes nimpha 群体死亡的原因

我们研究了 2012 年至 2014 年在波兰波兹南附近的 eusocial 纸黄蜂 Polistes nimpha 的种群，以确定死亡原因并分析繁殖季节（5 月至 9 月）期间活跃巢穴数量的变化。为期 3 年的研究结果表明，研究区域内 P. nimpha 死亡率 (51.9%) 的主要原因是哺乳动物的活动，可能是狐狸和野猪。黄蜂死亡的第二个主要原因是蚂蚁捕食（12%）。在繁殖后代出现后，308 个巢穴中只有 11 个（3.6%）表现出自然种群数量下降。