McGee Sean, Whitfield-Aslund Melissa, Duca Daiana, Kopysh Nicole, Dan Tereza, Knopper Loren, Brewer Larry
Bayer CropScience, LP, Research Triangle Park, NC, USA.
Stantec Consulting Ltd, Stoney Creek, ON, Canada.
PeerJ. 2018 Nov 7;6:e5880. doi: 10.7717/peerj.5880. eCollection 2018.
The objective of this study was to quantify consumption of clothianidin-treated corn seed by birds following standard planting practices. Based on post-planting seed counts on 21 fields in southwestern Ontario, Canada, between 29 and 813 seeds/ha (mean of 224 ± 167 (SD)) were estimated to remain on the soil surface immediately post planting (i.e., less than one seed per 10 m). This represents between 0.03 and 1.2% of the total sown seeds. The number of seeds missing on each field on the third day after planting as a result of any process (e.g., removal by foraging birds or mammals or burial as a result of heavy rains) ranged from 0 to 136 seeds/ha (0 to 0.0136 seeds/m). Behavior monitoring of individual birds and 24 h remote video surveillance were deployed to investigate how much of the treated seed remaining on the soil surface was consumed by birds. Spotting scopes were used to monitor the full duration of the field visits of 596 individual birds during morning hours for three consecutive days after planting on the 21 fields. Two birds were observed consuming treated seeds (one seed each) and three birds consumed seeds for which the treatment status could not be visually confirmed. Additionally, constant (24 h) video surveillance for 2-4 days immediately after planting was deployed at 24 areas where multiple treated seeds were found on the soil surface. Across 1,380 h of collected video footage (including both day and night periods), no birds were observed to consume any treated seeds. This study provides field evidence of two factors that determine exposure of birds to clothianidin-treated corn seeds: (1) standard sowing practices in Ontario are effective at burying treated seeds such that the proportion of sown seeds that remain on the soil surface after planting is low, and (2) birds monitored on these fields consumed very few of the clothianidin-treated corn seeds remaining on the soil surface after planting. As these results are dependent on planting techniques and seed characteristics, they are not necessarily applicable to other types of clothianidin treated seed.
本研究的目的是量化按照标准种植方法种植后鸟类对噻虫胺处理过的玉米种子的消耗量。根据加拿大安大略省西南部21块田地种植后的种子计数，估计种植后立即留在土壤表面的种子数量为29至813粒/公顷（平均为224±167（标准差））（即每10米少于1粒种子）。这占播种种子总数的0.03%至1.2%。种植后第三天，由于任何过程（例如，觅食的鸟类或哺乳动物移除或大雨掩埋），每块田地上缺失的种子数量在0至136粒/公顷（0至0.0136粒/米）之间。对个体鸟类进行行为监测并进行24小时远程视频监控，以调查留在土壤表面的经处理种子有多少被鸟类消耗。在种植后的连续三天上午，使用定点观测镜对21块田地上的596只个体鸟类的田间访问全过程进行监测。观察到两只鸟食用了经处理的种子（各1粒），三只鸟食用了无法目视确认处理状态的种子。此外，在发现土壤表面有多个经处理种子的24个区域，在种植后立即进行了2至4天的连续（24小时）视频监控。在收集的1380小时视频片段（包括白天和夜间）中，未观察到鸟类食用任何经处理的种子。本研究提供了两个决定鸟类接触噻虫胺处理过的玉米种子的因素的实地证据：（1）安大略省的标准播种方法有效地掩埋了经处理的种子，因此种植后留在土壤表面的播种种子比例很低；（2）在这些田地上监测到的鸟类食用种植后留在土壤表面的噻虫胺处理过的玉米种子的数量很少。由于这些结果取决于种植技术和种子特性，它们不一定适用于其他类型的噻虫胺处理过的种子。
