The Effects of Crop Protection Pesticides on Honey Bee Forager Survival

摘要

Honey bees (Apis mellifera) account for most of the approximately $ 16 billion in bee pollination services contributed annually to agriculture in the United States. Among the many crops pollinated by honey bees is almond, which relies almost entirelyon honey bees for pollination. The almond industry in California produces about 80 percent of the almonds consumed worldwide and employs approximately 60 percent of all managed honey bee hives to provide pollination services during the crop's bloom in mid to late winter. In protecting almond orchards from various pests and pathogens, heavy chemical treatments are employed during bloom. Despite their ubiquitous use, the effects on honey bee health of the various pesticides used repeatedly in almond orchards are not well understood. In particular, only a handful of studies looking at the effects on honey bees of fungicide formulations in almonds have been reported to negatively impact brood survival and induce sub-lethal effects on thermoregulation in adult workers. In addition, synergistic effects of select fungicides and insecticides on worker and colony mortality have been reported. Recently, an examination of various pesticides including insecticides, a fungicide and a herbicide in other crop systems such as cotton, rice and corn revealed significant negative impacts of these chemicals on worker survival. Because honey bees exhibit age-based division of labor, only workers over 21 days of age serve as foragers. Therefore, foragers, as the only workers that spend time outside the hive, comprise the age group susceptible to direct exposure to agro-chemical applications or contact with residues left over from such aDDlications.