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Bees neonicotinoid pesticides Decrease Bee Flight distance to a third


scattering of colorless crystals with a & # 39 is the most popular and widespread insecticide in the world. Called imidacloprid, he used to kill and control various insects: termites, beetles, grasshoppers and stink bugs. This, however, is not intended to destroy the bees – a round, fuzzy, essential pollinators. Despite the lack of intent, it is increasingly clear that imidacloprid affects the bee, so the study released on Monday showed that he could bring down their rates.

The researchers write in the journal Ecology and Evolution that in the context of research, bumblebees imidacloprid exposure in doses, they would have faced in the fields fly much shorter distances and for less time than unexposed bees. Imidacloprid belongs to the class of neurotoxic pesticides called neonicotinoids, and it is already banned in Europe because of its impact on bees. However, it is regularly used in other countries, including the United States. If the ban will be applied in the United Kingdom after Brexit currently unknown.

Daniel Kennan with the & # 39 is the first year Ph.D. student at the Imperial College in the UK and the first author of the study. he says return he hopes that these findings shed a little more light on how the potential of bee foraging seven & # 39; ads affected landscapes exposed to pesticides in general. In the United Kingdom, views were more fragmented growth of agricultural production over the past 50 years. As the bee population change, in turn, with the & # 39 is ambiguous: Two of Britain 25 species of bumble bees become extinct, while eight species are endangered. Oddly enough, the two most common types of numbers actually increased.

Bumblebees round and inaccurate than honeybees.

In this study, Kennan and his colleagues evaluated the kinds of bees Bombus terrestris AudaxCommercial company filed three colonies, each of which contains a queen and about a hundred workers. Then hives have received a dose of imidacloprid, which was equal to what they may face, say, the American field. Their flight was tested with something called a "Flight mill" – spinning device, which is a bit like a terrifying chair swing ride. Small metal disks were attached to the backs of bees, which are connected to a magnet on the machine. The idea of ​​this device is that the bees can fly in a circle while scientists can observe them under controlled conditions.

Originally discovered bees were sent to the state of hyperactivity – that fly much faster than the bee, not exposed to the pesticide. However, after this increase in energy consumption, they are rapidly slowed down. The findings suggest that workers who eat contaminated food, when a gathering may not be able to make it back to the colony after irradiation.

bee design study
The study design, including mill flight (a) and b, pesticide exposure chamber (s), and a close-up of a magnet on the back of a bee (g).

"We were very surprised by the magnitude of the effect on flight endurance," says Kennan. "Naked workers only flew a distance of one-third of non-exposed workers, and this can have serious & # 39; serious consequences in terms of the resources that foraging bees are capable of achieving."

Hyperactivity condition was probably because the induced neonicotinoids stimulate the activity of the neuron, which makes sense, as imidacloprid has been made to mimic nicotine – which of the & # 39 is a stimulant. Previous studies at Imperial College found that neonicotinoids focused on nerve receptors of insects, which are similar to the receptors targeted by nicotine in mammals. In turn, the researchers showed that bees exposed to these pesticides to develop a taste for them, becoming addicted.

Although more research is needed to know exactly why pesticides have made it so difficult bumblebee to fly, it is also known that imidacloprid and clothianidin pesticide, negatively affects the nervous system of bees and literally change their genes. If different types of bees are going to survive in the next decade and pollinate our food, it is likely that some of the pesticides regulation will play a role.


On the & # 39; emergence of agriculture land use change poses a number of problems that insect pollinators such as eusocial bees, must be overcome. The resulting fragmentation and loss of suitable habitat foraging, combined with exposure to pesticides may increase the requirement for foraging, in particular, the ability to collect or to achieve sufficient resources under so much stress. Understanding the effects that pesticides have on the flight It is very important if we want to measure the success of the colony in this changing landscape. Neonicotinoids with & # 39 is one of the most widely used class of pesticides around the world, as well as the impact on the bee was associated with a reduction in the efficiency and foraging homing ability. One explanation for these effects can be that the flight elements are exposed to, but apart from a few studies on honeybees (Apis MELLIFERA), it's almost not been tested. Here we used the mill flight to investigate how exposure to realistic field (10 ppb) acute dose of imidacloprid affected flight of wild insect pollinators, bumblebee, Bombus terrestris Audax. Interestingly, the observations showed open work collided with a much higher rate than in the first ¾ km flight. It is obvious hyperactivity, however, may have cost as open work showed reduced flight range and duration of about one-third of the control workers have been able to achieve. Given that the bumblebees with & # 39 is a central place foragers, flight endurance deterioration can translate to a decrease in the potential field of feed, reducing the richness, diversity and nutritional quality of food available, while potentially reducing the chances of pollination services.

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