The neonicotinoid insecticide imidacloprid disrupts bumblebee foraging rhythms and sleep. Tasman et al.

Neonicotinoids have been implicated in the large declines observed in insects such as bumblebees, an important group of pollinators. Neonicotinoids are agonists of nicotinic acetylcholine receptors that are found throughout the insect central nervous system and are the main mediators of synaptic neurotransmission. These receptors are important for the function of the insect central clock and circadian rhythms. The clock allows pollinators to coincide their activity with the availability of floral resources and favourable flight temperatures, as well as impacting learning, navigation and communication. Here we show that exposure to the field relevant concentration of 10 µg/L imidacloprid caused a reduction in bumblebee foraging activity, locomotion and foraging rhythmicity. Foragers showed an increase in daytime sleep and an increase in the proportion of activity occurring at night. This could reduce foraging and pollination opportunities, reducing the ability of the colony to grow and reproduce, endangering bee populations and crop yields. Tasman et al Figure 1 contains the activity counts for each individual forager for 5 days of LD (collected using the LAM), in 30 minute bins. Each .txt file is for a single bee, first line shows the run name, followed by the monitor number and then the channel number, e.g. 2015CtM022C08. Here run name is 2015Ct, monitor is number 22 and channel is number 8. This is followed by the date on which the run started. The second line shows the number of bins, the third line shows the length of these bins in minutes and the 4th line shows the time of the first bin, e.g. 09:00. The activity count for each bin is then listed. The file contains the data for colonies 1-3, which were combined for analysis of activity levels and circadian rhythms. Each folder contains a text file detailing which individual received which treatment, e.g. control, IM 1 ug/L or IM 10 ug/L. Tasman et al Figure 2 contains the same type of data as in Figure 1 but for 5 days of DD. Tasman et al Figure 3 contains the same type of data as in Figure 1, for 5 days of LD in both 1 min and 30 mins bins, which was used for sleep analysis. Tasman et al Figure 4 contains excel spreadsheets of the readout for the RFID reader, for the 5 days of LD. There is a folder for each of the three runs, within which there are folders for each day of the run and a spreadsheet for each 30 min bin within that day. These spreadsheets show each read from the RFID reader, listing (from left to right) the date and time of the read, the reader number and the ID of the bee being read. Consecutive reads less than 1 min apart from the same bee were counted as one activity bout. Days start at 9am except Day 1 which starts at 10am. There is a text file showing the colony number and treatment for each reader in each run. This was analysed for foraging activity and rhythmicity. Tasman et al Figure 5 shows the same type of data as in Figure 4 but for 5 days of DD.新烟碱类杀虫剂（Neonicotinoids）被认为与熊蜂等重要传粉昆虫类群的大规模种群衰退密切相关。新烟碱类是烟碱型乙酰胆碱受体（nicotinic acetylcholine receptors）的激动剂，该受体广泛分布于昆虫中枢神经系统中，是突触神经传递的主要介导因子。此类受体对于昆虫中枢生物钟与昼夜节律的功能至关重要。生物钟可帮助传粉昆虫将其活动与花源可获得性、适宜飞行温度相匹配，同时还会影响其学习、导航与通讯行为。本研究表明，暴露于10 μg/L吡虫啉（imidacloprid）这一田间相关浓度下，会导致熊蜂的觅食活动、运动能力及觅食节律出现下降。觅食蜂的日间睡眠时间增加，且夜间活动占比升高。这可能会减少觅食与传粉机会，削弱蜂群的生长与繁殖能力，进而威胁蜜蜂种群与作物产量。 Tasman等人的图1包含了5天长光照（LD）条件下每只觅食蜂的活动计数数据（采用LAM设备采集），数据以30分钟为时间窗进行分箱。每个.txt文件对应单只蜜蜂，首行标注运行名称、监测器编号与通道编号，例如"2015CtM022C08"，其中运行名称为2015Ct，监测器编号为22，通道编号为8。紧随其后的是实验运行的起始日期。第二行标注分箱总数，第三行标注各分箱的时长（单位：分钟），第四行标注首个分箱的起始时间，例如09:00。随后依次列出每个分箱的活动计数。该文件包含了1-3号蜂群的数据，这些数据经合并后用于分析活动水平与昼夜节律。每个文件夹均包含一个文本文件，用于说明每只个体所接受的处理方式，例如对照组、1 μg/L吡虫啉处理组或10 μg/L吡虫啉处理组。 Tasman等人的图2包含与图1同类别的数据，但对应5天长暗周期（DD）条件。 Tasman等人的图3包含与图1同类别的数据，为5天长光照条件下以1分钟和30分钟为时间窗分箱的数据，该数据用于睡眠分析。 Tasman等人的图4包含射频识别（RFID）阅读器的读数Excel表格，对应5天长光照条件。每个实验运行对应一个文件夹，文件夹内包含实验每日对应的子文件夹，以及当日每个30分钟分箱对应的电子表格。这些电子表格展示了RFID阅读器的每一次读取记录，从左至右依次为读取的日期与时间、阅读器编号以及被读取蜜蜂的ID。同一蜜蜂的两次读取间隔小于1分钟时，将被计为一次活动事件。实验天数从上午9点开始，但第1天从上午10点开始。另有一个文本文件，用于说明每个实验运行中各阅读器对应的蜂群编号与处理方式。该数据被用于分析觅食活动与节律性。 Tasman等人的图5包含与图4同类别的数据，但对应5天长暗周期条件。