Toxic and Repellent Effects of Pyrethroids Used in Orchards on the Honey Bee, \u3ci\u3e Apis mellifera \u3c/i\u3e L. (HYMENOPTERA: APIDAE)

Managed honey bee colonies provide valuable pollination services and are rented by fruit orchards to improve fruit quality and yield. The placement of colonies in this agricultural setting increases the possibility of exposure to pyrethroids used for broad-spectrum pest control in orchards. Although highly toxic to bees, pyrethroids are believed to pose a relatively low hazard due to their low application rates in the field as well as their contact repellent properties. Previous studies have noted a decrease in foraging visits following pyrethroid application possibly preventing bees from acquiring a lethal dose in the field. This research quantified behaviors associated with sub-lethal exposure to orchard-applied pyrethroids, lambda-cyhalothrin, esfenvalerate, and permethrin, using video tracking software, Ethovision XT (Noldus Information Technologies). Bee locomotion, social interaction, and time spent near a food source were measured over a 24-hour period. This project also evaluated the repellency of pyrethroids currently used in orchard production to foraging worker bees under artificial feeding conditions and in a field setting. The objective of this study was to achieve a better understanding of behavioral effects associated with sub-lethal pyrethroid exposures in the laboratory and determine if a field-relevant exposure would result in repellency of foragers. This research will aid in the development of better-informed management decisions made by both growers and beekeepers and provide risk assessment tools and protocols to regulatory agencies seeking to quantify sub-lethal pesticide effects on pollinators. Advisers: Marion Ellis and Blair Siegfrie