Bees provide pollination services in both agricultural and natural ecosystems. However, invasive ants that exploit floral nectar in these landscapes can compete with bees for resources, with implications for pollinator resource acquisition, plant fitness, and, ultimately, ecosystem function. While interference competition has been described between bees and nectivorous, non-pollinator antagonists, the behaviors and sensory mechanisms involved remain largely unresolved. Here, we studied the mechanisms by which invasive Argentine ants influence bee nectar foraging behavior. In a series of laboratory assays, we assessed the foraging behavior of bumble bees (Bombus impatiens) in response to live Argentine ants (Linepithema humile) or to a subset of ant chemical cues. Bees were clearly deterred by live ants at a nectar source: they consumed less, fed less frequently, and fed for a shorter duration when live ants were present. Bees were also deterred by a combination of olfactory and gustatory ant chemical cues, consistent with both innate and learned avoidance behavior. Naïve and ant-experienced bees were deterred through chemosensation of ants, feeding less from nectar infused with ant chemicals as compared to nectar lacking ants or their associated cues. Some ant-experienced bees showed a unique behavior, displaying aggression toward ants as well as in response to ant chemicals. The marked effects of this invasive ant on bee foraging behavior—through physical interaction and chemical cues—highlights Argentine ants as a serious pest whose control should be considered when developing pollinator conservation and management strategies.

蜜蜂在农业和自然生态系统中提供授粉服务。然而，在这些景观中利用花蜜的入侵蚂蚁可以与蜜蜂争夺资源，对传粉者资源获取、植物适应性以及最终生态系统功能产生影响。虽然已经描述了蜜蜂和食蜜、非传粉者拮抗剂之间的干扰竞争，但所涉及的行为和感觉机制在很大程度上仍未得到解决。在这里，我们研究了入侵的阿根廷蚂蚁影响蜜蜂花蜜觅食行为的机制。在一系列实验室分析中，我们评估了大黄蜂 ( Bombus impatiens ) 对活体阿根廷蚂蚁 ( Linepithema humile ) 的觅食行为) 或蚂蚁化学线索的一个子集。蜜蜂显然被花蜜来源处的活蚂蚁吓退了：当有活蚂蚁存在时，它们吃得更少，喂食的频率也更低，喂食时间也更短。蜜蜂也被嗅觉和味觉蚂蚁化学线索的组合所吓倒，这与先天和习得的回避行为一致。天真的蜜蜂和蚂蚁经验丰富的蜜蜂通过对蚂蚁的化学感应而被吓退，与缺乏蚂蚁或其相关线索的花蜜相比，它们较少从注入蚂蚁化学物质的花蜜中取食。一些经历过蚂蚁的蜜蜂表现出独特的行为，表现出对蚂蚁的攻击性以及对蚂蚁化学物质的反应。