Meeting Abstract

P2.168  Sunday, Jan. 5 15:30  The neonicotinoid pesticide thiamethoxam affects motor responses and foraging behavior of honey bees. BLATZHEIM, L*; BOWER, C; POLK, T; IKIZOĞLU, D; KARAHN, A; LEVINSON, B; GUNEŞ, N; ÇAKMAK, I; WELLS, H; HRANITZ, J.M.; Southwester Oklahoma State University; Bloomsburg University of Pennsylvania; Southern Nazarene University; Uludağ University, Bursa, TURKEY; University of California, San Diego; University of Tulsa blatzheiml@student.swosu.edu

Neonicotinoid compounds are the next generation of nicotine-like substances (e.g., thiamethoxam) that are currently widely used in agriculture. Neonicotinoids have been implicated as causal agents in honey bee colony collapse disorder (CCD), since the onset CCD coincided with the widespread use of neonicotinoids. The doses that bees encounter in agriculture are well below the LD50 and considered “safe” but sublethal effects may be important. Our goal was to study the sublethal effects of thiamethoxam on the motor coordination of captive bees and foraging behavior of free-flying bees. We tested doses at 1/5 to 1/500 of the LD50 for motor responses after 4 h of administration for harnessed bees and 60-150 minutes after administration in free flying bees. At 4 h post-administration, motor coordination was assessed for antennal movement, proboscis extension reflex, leg, and abdomen movement. Motor coordination of bees treated with 1/5 LD50 was lower than motor coordination of control bees. We assessed the visitation rate and foraging abilities of free-flying bees on an artificial flower patch. The return rate was significantly lower for pesticide-treated bees at doses as small as 1/10 LD50 and the ability of foragers to distinguish between high and low sucrose nectar was impaired at doses higher than 1/50 LD50. Our results show significant sublethal effects of thiamethoxam, impairing basic motor coordination and foraging performance of honey bees at doses substantially lower than the LD50.