It has been ten years since the “Research Unit” Bees and Environment “has developed this type of test unique in the world, which has made it possible to prove the harmful consequences of pesticides, including neonicotinoids, on foraging colonies.
Freddie-Jeanne Richard, Director of Research in Biology and Bee Behavior in this Institute, works with emerging honey bees, which she puts by dozen in plexiglass “cagettes” equipped with tubes filled with a sweet solution.
Just out of their cell, they are exposed to a pesticide through food. “”We have been able to demonstrate that pesticides (…) In the doses that are currently used, have non -lethal impacts (which do not death) on pollinators“She explains.
However, the use of neonicotinoids, even in small quantities, can “alter bee behavior“, which can have”repercussions on the scale of the individual or the colony“Said the researcher.
Concretely, neonicotinoids, just like other pesticides or fungicides, can have effects on “Communication and orientation capacities of bees“, In particular workers who regularly emerge from the hive to feed the colony and ensure the survival of the brood.
Eggs, larvae and nymphs can also be contaminated by bees in contact with pesticide “When they come together, collect nectar or pollen on the flowers“Explains Freddie-Jeanne Richard.
The Queen, who holds the monopoly of reproduction within the hive, can also see her altered capacities and thus undermine all the development of the colony.
Empty hives
After being exposed to a pesticide, the bees are individually marked by a chip. Julie Fourrier, project manager in experimental ecotoxicology, manipulates them with care using an entomology clamp.
With only a small point of glue, it has an RFID chip (radio frequency identification) on their backs on their backs. They can also be equipped with a tiny QR-Code, a more recent device.
“”The arrival of this technology allowed us major advances in terms of monitoring the activity of bees“She says.
Dressed in their combination, scientists then release them about one kilometer from their colony, to follow their ability to return to the hive. The latter is equipped with a counter attached to the fleas, which records the precise moment of entry and exit of the fogger.
Bees not coming back “will be lost bees that will eventually die on the ground, since a domestic bee cannot live outside its colony“Explains Julie Fourrier.
This technology revolutionized research on the impact of neonicotinoids on bees. “”This allowed us to respond to the concerns of beekeepers“Who saw completely empty hives, due to disoriented bees by the effect of pesticides on their nervous system.
This is why, for Cédric Alaux, Director of Research in Biology and Protection of Bees at INRAE, if the National Assembly adopts the text proposed by Senator Les Républicains Laurent Duplomb, who must be examined in the hemicycle at the end of May, we could attend “A step back, while there is a lot of evidence of () toxicity“Neonicotinoids.
This bill which hears “Raise constraints to the exercise of the farmer profession“Aims to authorize by derogation and for certain sectors (hazelnut, beet) the use of a type of neonicotinoid: acetamipride. This product has been prohibited in France since 2018, after a long mobilization of beekeepers and the scientific community.
“”The toxicity of neonicotinoids has been proven twenty times, both in laboratory condition but also in the field“, Underlines Cédric Alaux, determined to continue to improve these technologies for new advances intended to protect these precious insects.