Sublethal concentrations of clothianidin affect honey bee colony growth and hive CO concentration.

The effects of agricultural pesticide exposure upon honey bee colonies is of increasing interest to beekeepers and researchers, and the impact of neonicotinoid pesticides in particular has come under intense scrutiny. To explore potential colony-level effects of a neonicotinoid pesticide at field-relevant concentrations, honey bee colonies were fed 5- and 20-ppb concentrations of clothianidin in sugar syrup while control colonies were fed unadulterated syrup. Two experiments were conducted in successive years at the same site in southern Arizona, and one in the high rainfall environment of Mississippi.

Landscape factors influencing honey bee colony behavior in Southern California commercial apiaries.

Colony brood levels, frames of bees (adult bee mass) and internal hive temperature were monitored for 60 colonies for each of two years as they were moved from agricultural, tree crop and mountain landscapes in southern California to blueberry and almond pollination sites. Hive weight was also continuously monitored for 20 of those hives for 6 weeks for both years, during commercial pollination. Pesticide residues in wax, honey and beebread samples were analyzed by composite apiary samples.

Exposure to sublethal concentrations of methoxyfenozide disrupts honey bee colony activity and thermoregulation.

Methoxyfenozide is an insect growth regulator (IGR) commonly used in agriculture to simultaneously control pests and preserve beneficial insect populations; however, its impact on honey bees in not fully understood. We conducted field and laboratory experiments to investigate bee health in response to field-relevant concentrations of this pesticide. Significant effects were observed in honey bee colony flight activity and thermoregulation after being exposed over 9 weeks to supplemental protein patty containing methoxyfenozide.