Data from: The effect of repeated, lethal sampling on wild bee abundance and diversity

1. Bee pollinators provide a critical ecosystem service to wild and agricultural plants but are reported to be declining world-wide due to anthropogenic change. Long-term data on bee abundance and diversity are scarce, and the need for additional quantitative sampling using repeatable methods has been emphasized. Recently, monitoring programmes have begun using a standardized method that employs a combination of pan traps and sweep netting, resulting in lethal sampling of bees. This standardized method can remove a large number of bees from sites during each sampling day, raising concern that the sampling itself could have a negative effect on bee populations. 2. We conducted an experiment to assess whether lethal sampling for bees using pan traps and netting affected bee abundance and diversity when done every two weeks throughout a season and over multiple years. We compared bee abundance, richness, evenness and functional group composition between sites that had been sampled every two weeks from 2009 to 2012 to similar sites not previously sampled. 3. We found that the standardized method for sampling bees, with specimens from 132 morphospecies, did not affect bee communities in terms of abundance, rarefied richness, evenness, or functional group composition. Thus, our results indicate that the bee communities we sampled are robust to such sampling efforts, despite removing an average of 2862 bees per season. 4. We discuss several explanations for why sampling did not affect bee abundance or community structure, including a density-dependent response to reduced competition for resources. 5. These results suggest that bee monitoring programmes sampling once every two weeks with pan traps and netting will not affect bee community structure. We urge researchers monitoring bees to utilize standardized protocols so that results can be compared across space and time.

1. 传粉蜜蜂（bee pollinators）为野生植物与农业作物提供了至关重要的生态系统服务，但据报道，受人为活动改变的影响，全球范围内的蜜蜂种群正呈下降趋势。目前关于蜜蜂种群数量与多样性的长期监测数据十分匮乏，学界已强调需采用可重复的方法开展更多定量采样工作。近年来，相关监测项目开始采用一种标准化采样方案，该方案结合了色盘诱捕器（pan traps）与扫网采样（sweep netting），属于蜜蜂致死性采样（lethal sampling）。这种标准化方法在每次采样日均可从样地中捕获大量蜜蜂，由此引发了一项担忧：采样活动本身可能会对蜜蜂种群产生负面影响。
2. 本研究开展了一项控制实验，以评估在整个生长季内每两周采样一次、且持续多年的情况下，采用色盘诱捕与扫网方式开展的蜜蜂致死性采样是否会对蜜蜂种群数量与多样性造成影响。我们对比了2009年至2012年间每两周采样一次的样地，与此前未开展过采样的匹配样地之间的蜜蜂种群数量、物种丰富度、均匀度以及功能群组成差异。
3. 本研究发现，这种针对蜜蜂的标准化采样方法（共采集到132个形态种（morphospecies）的标本）并未对蜜蜂群落的种群数量、稀疏化物种丰富度、均匀度以及功能群组成产生显著影响。尽管每次采样季平均移除了2862只蜜蜂，但研究结果表明，我们所采样的蜜蜂群落对这类采样活动具有较强的耐受性。
4. 本研究探讨了采样未对蜜蜂种群数量与群落结构造成影响的多种潜在机制，其中包括资源竞争减少所引发的密度依赖响应。
5. 上述研究结果表明，采用色盘诱捕与扫网方式、每两周采样一次的蜜蜂监测项目，不会对蜜蜂群落结构造成负面影响。我们呼吁开展蜜蜂监测工作的研究人员采用标准化采样方案，以便在不同空间与时间尺度上实现研究结果的横向对比。