Researchers from Harvard University developed a tracking system to determine that neonicotinoids reduce activity in bumble bee colonies
Neonicotinoids are commonly used insecticides that eliminate several crop pests. However, these pesticides have insidious effects on bees. High doses of these neurotoxins in the pollen and nectar collected by bees harm their memory and ability to gather food. Now, a team of researchers from Harvard University developed a new tracking technique to determine that neonicotinoids reduce activity in bumble bee colonies, thereby making bees less concerned about offspring. This in turn arises challenge for the colony to regulate nest temperature. The research was published in the journal Science on November 09, 2018.
The researchers examined the bees’ collective behavior after exposure to the chemicals in order to determine how the pesticides were affecting colonies. To track the bees, uniquely patterned 3-by-4-millimeter tags were glued onto the backs of several bumble bees. A robotic equipment from a fruit fly lab was used to assemble a moveable platform with two high-resolution cameras. The cameras monitored several bumble bee colonies by picking up the movement of the tags. The data was later sent to computers for analysis. Nine colonies were given sugar syrup laced with six parts per billion of a common neonicotinoid called imidacloprid. The researchers found that overall level of activity of the bees and their social interactions decreased over a 12-day experiment period. Bees in control colonies were found to spend around 25% of the night caring for the brood, whereas the pesticide-consuming bees spent less than 20%.
Further experiment revealed that imidacloprid can restrict the ability of colonies to regulate their temperature. According to Richard Gill, a bee ecologist at Imperial College London, a hive requires to stay at a constant temperature for proper development of colony’s larvae. To learn more about how pesticides and temperature interact, the researchers are focused on developing tools for tracking and manipulating temperature in colonies. According to James Crall, an animal behavior biologist at Harvard University, the system of automated video surveillance can be used to make pesticide testing faster, cheaper, and more sophisticated.