Abstract Activity traps (ATs) are a widely used method of sampling water beetles (Coleoptera). This case study attempts to investigate the effect of mouth size and trapping effort on the performance of the ATs and reveal sex ratios and proportions of morphs in dimorphic females in populations of Dytiscidae and Noteridae in one particular area of Udomelsky District, Tver Oblast, Russia. ATs are more selective compared to hand netting but make it possible to collect a greater number of abundant species with relatively little expenditures of effort and time. The width of the trap mouth has no effect on efficiency. Long-time (48 h exposure) traps are not more efficient than short-time (24 h) ones, in terms of the relative intensity of collecting individuals and species. The applied number of ATs (up to 330 trap-days) was not sufficient to reveal the full diversity of diving beetles in the studied waterbodies.

中文翻译：

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寻找使用活动陷阱收集龙虱科和睡莲科（鞘翅目）的更好策略：俄罗斯中欧当地动物群的案例研究

摘要 活动陷阱（ATs）是一种广泛使用的水甲虫（鞘翅目）采样方法。本案例研究试图调查嘴巴大小和诱捕力度对 AT 性能的影响，并揭示俄罗斯特维尔州乌多梅尔斯基区一个特定区域的龙虱科和睡莲科种群中双态雌性的性别比例和变体比例。与手工网相比，ATs 更具选择性，但可以用相对较少的精力和时间来收集更多的丰富物种。捕集口的宽度对效率没有影响。就收集个体和物种的相对强度而言，长时间（48 小时暴露）陷阱并不比短时间（24 小时）陷阱更有效。