Effects of residual doses of neonicotinoid (imidacloprid) on metabolic rate of queen honey bees Apis mellifera (Hymenoptera: Apidae)

Abstract

Bees are key regulators in the maintenance of global biodiversity and food security. Overwhelming evidence has shown elevated colony losses for honey bees and a decrease in the abundance of other pollinators. Insecticides of the neonicotinoid type have been associated with these losses, but few studies have explored how residual exposure doses affect the queen’s energy metabolism. Here, we studied how a residual dose of neonicotinoid (imidacloprid), combined with reproductive status (virgin and inseminated) affects honey bee queen’s metabolism. We conducted the same experiment in two geographical locations (Chile and Colombia) and found a strong reduction of standard metabolic rate (SMR) in insecticide-treated queens (Chilean queen bees 11.3% reduction in watt output; Colombian queen bees 11.7% reduction in watt output). No effects were found when comparing reproductive condition on SMR. We will highlight the possible consequences of a weak honey bee queen’s performance on colony stability.