Scientists said they’ve found that exposure to the neonicotinoid pesticide imidacloprid produces complex changes in the social behaviors and activities of bumblebees – a very bad thing for creatures who rely on their colonies to survive. Bumblebees exposed to imidacloprid became less social and spent less time together. The bees also spent less time nursing larvae, foraging and constructing the wax canopy which insulates and regulates the temperature of the hive. These findings match earlier studies, but by using an automated, robotic platform for continuous, multicolony monitoring of uniquely identified workers, the study found that the behavioral changes in the bees varied over the course of a day. Behavioral changes appeared to peak at night and when the temperature was cooler. Bees exposed to field-realistic concentrations of imidacloprid experienced problems regulating temperature, which may have been exacerbated by a tendency to move to the edges of the nest rather than remain clustered together at the center.
The complex changes to bee behavior with neonic exposure highlight the value of using technology to examine the impacts of environmental changes not just on a large scale, but even down the hive.
Source: Courthouse News Service, 8 November 2018
James D. Crall et al. Neonicotinoid exposure disrupts bumblebee nest behavior, social networks, and thermoregulation. Science 09 Nov 2018: Vol. 362, Issue 6415, pp. 683-686