The influence of sub-lethal neonicotinoid doses and ambient temperature on individual Apis mellifera scutellata flight efficiency

Abstract

Honey bee (Apis mellifera) thermoregulation plays an integral part in their behaviour and physiology and has been shown to be vulnerable to the effects of neonicotinoid insecticides. Flight muscles are a crucial source of physiological heat as well as being vital for behavioural heat regulation, and are negatively affected by neonicotinoid insecticides. In this study, we evaluated the flight efficiency and capacity of Apis mellifera scutellata under the influence of both elevated ambient temperatures and sublethal neonicotinoid exposure. The various aspects of flight; success, distance, speed, and duration, were not notably affected by these factors. However, the honey bees’ ability to initiate a successful flight was significantly affected by neonicotinoid exposure. Such a reduction in honey bee flight capacity, and flight muscle function in general, especially under the increasing frequency and intensity of hot weather events, is cause for concern when considering legislation and use of these neonicotinoids in the agricultural and suburban setting.