But two new studies have found that a commonly used pesticide disturbs the lake in bees and flies – with major consequences for the important insects.
In one study, researchers looked at the effect of pesticides on bumblebee behavior by giving the creatures nectar sugar twisted with neonicotinoids – one of the most commonly used pesticides – and then tracking their movements in a feeding path.
The effect of the pesticide – equivalent to the amount a bee would encounter in the wild – was strong.
“It seems to interfere with the body clock in feeding bumble bees – they feed much less, more of this feed takes place at night, and they sleep much more during the day. It causes a mistiming of their normal behavior,”
This, she explained, could have serious consequences: “It’s quite worrying because other studies and our studies show that the motivation to seek food has decreased.”
Many plants – including fruits and vegetables that we eat and feed our pets – rely on pollinators, such as bees, to reproduce.
Nearly 90% of wild plants and 75% of the leading global crops depend on deep pollination, notes the World Wildlife Fund.
Bees take on a large portion of this workload: Pollinators, often honey bees, are responsible for one in three bites of food, according to the U.S. Department of Agriculture, increasing crop values in the United States by more than $ 15 billion each year.
But bees and other pollinators are threatened by widespread use of pesticides, habitat loss, the climate crisis and parasites, so much so that the odds of spotting the hard-working bumble bee in Europe and America have fallen by more than 30% since the last century. .
Tasman warned that bees are now “quite sluggish, and they still go out less often.”
“If the time when they manage to go out and feed is at night, when flowers are not available, it will greatly reduce how successful they are at gathering the food that the colony needs to grow and reproduce, “Tasman, lead author of the study, said.
In another study published Thursday, the researchers focused their attention on flies – again, exposing them to neonicotinoids and then using infrared rays to monitor how this affected movement.
The results showed that the pesticide worked directly on the cells in the brain that run the body clock, which determines when sleep and activity occur during the day – and confuses them.
“It seems that these pesticides freeze these cells in daytime form, so the body does not know if it is daytime or night,” Tasman said, adding that it is very likely that the same kind of mechanism that happens in the flies, also happens. and beers.
Researchers say their research could help us further understand how these pesticides affect vulnerable insects.
“It also gives us tips on what we could investigate if we were to make more pest-specific pesticides – if we understand exactly how they work in insects, we might be able to make some that only work on pests,” Tasman added.