Last updated June 13, 2018 at 4:47 pm
Study reveals negative consequences for queen.
Credit: N Norozoff / iStock
The bumblebee population is being affected by insecticides and, more surprisingly, a dull diet.
Both have “unique negative consequences” on nesting queens, according to new research, including delayed nest initiation and lower brood numbers in the nest. They do partially recover if exposure to pesticides is only temporary, however.
The study carried out at the University of California, Riverside was one of the first to look at the impact specifically on the queen, rather than the worker caste.
There is growing evidence that neonicotinoid pesticides affect pollinating insects. In a laboratory experiment, the researchers found that queen bumblebees exposed to sublethal doses of a similar insecticide died at higher rates and had smaller brood sizes.
They also examined the effects of a pollen diet that came from a single plant species and found this also decreased brood production, though not as much as the insecticides.
“Although insecticide exposure had stronger negative impacts, a monofloral pollen diet on its own was sufficient to reduce brood production in nesting queens,” they write in a paper published in Proceedings of the Royal Society B: Biological Sciences.
“These findings speak to the unique biology of the queen caste in bumblebees and the special challenges they face in response to global change.”
