1) Many wild bee species interact with soil either as a nesting substrate or material. These soil interactions create a risk of exposure to agrochemicals such as imidacloprid or other neonicotinoid pesticides that can persist in soil for months after application. At the landscape level, concentrations of imidacloprid residue in soil are limited to the immediate treatment area, and thus risks to soil-interacting bees could be low if they avoid contaminated soils. 2) We utilized Osmia lignaria (Say), a solitary cavity nesting bee which collects mud to partition and seal nests, and conducted two laboratory experiments to test whether nesting females select or avoid soils containing various levels of imidacloprid residue. For the first experiment, we assessed behavioral responses of females to treated soil utilizing a choice arena and pairing various choices of soil with imidacloprid residues ranging between 0 and 780 ppb. For the second experiment, we developed a laboratory assay to assess soil selection of actively nesting O. lignaria, by providing choices of contaminated soil between 0 and 100 ppb and 0 and 1,000 ppb to nesting females. 3) We found no evidence that O. lignaria females avoided any level of imidacloprid contamination, even at the highest residue level (1,000 ppb) in both the experiments, which may have implications for risk. The in situ nesting methodology developed in this study has future applications for research on soil or pollen preferences of cavity nesting Osmia species, and potential for breeding of O. lignaria in laboratory.

中文翻译：

---

梅森蜂（膜翅目：巨蛉科）没有避免使用吡虫啉处理过的土壤

1) 许多野生蜜蜂物种作为筑巢基质或材料与土壤相互作用。这些土壤相互作用产生了接触农药的风险，例如吡虫啉或其他新烟碱类农药，这些农药在施用后会在土壤中持续存在数月之久。在景观层面，土壤中吡虫啉残留物的浓度仅限于直接处理区域，因此如果蜜蜂避免受污染的土壤，它们与土壤相互作用的风险可能很低。2）我们利用蜂巢蜂（Say），一种收集泥浆以分隔和密封巢穴的孤腔筑巢蜂，并进行了两次实验室实验，以测试筑巢雌性是否选择或避免含有不同水平吡虫啉残留的土壤。对于第一个实验，我们评估了雌性对处理过的土壤的行为反应，利用选择场地并将各种选择的土壤与 0 至 780 ppb 之间的吡虫啉残留物配对。对于第二个实验，我们开发了一种实验室测定方法来评估积极筑巢的 O. lignaria 的土壤选择，通过为筑巢的雌性提供 0 到 100 ppb 和 0 到 1,000 ppb 之间的污染土壤选择。3) 我们没有发现任何证据表明 O. lignaria 雌性避免了任何水平的吡虫啉污染，即使在两个实验中的最高残留水平 (1,000 ppb) 下也是如此，这可能对风险有影响。本研究开发的原位筑巢方法可用于研究空腔筑巢 Osmia 物种的土壤或花粉偏好，以及在实验室培育 O. lignaria 的潜力。