Table 1. Effects of chronic Fipronil exposure on drone life cycle traits.

	Ctrl (n = 22)	Fip (n = 22)	p value
	mean ± SD	mean ± SD
Drone survival rate (%)	45.3 ± 22.8	39.8 ± 22.4	0.296
Drone maturity rate (%)	62 ± 9.6	64.3 ± 10.1	0.405
Semen volume (μL/drone)	0.83 ± 0.11	0.85 ± 0.11	0.602

At sexual maturity, which corresponded to the end of the exposure period, the hives were opened in order to capture 20-day-old cloistered drones and to collect semen. Drone survival and maturity as well as the average semen volume per drone were determined for each hive. The data represent the mean values ± standard deviations obtained from drone populations recovered from hives in 4 experiments monitored from 2012 to 2014 (n = 22). Statistical analyses were performed using a generalized linear mixed model with a random effect on the different experiments.