New studies appear to confirm that neonicotinoid pesticides are killing bees, even as chemical companies continue to tout their safety. An EU-wide ban is looking increasingly likely.
Image: picture-alliance/blickwinkel/McPHOTO
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Insecticides threaten bees
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Bees aren't just the makers of delicious honey, they play a crucial role in the world's agricultural systems. But they are slowly vanishing - due mainly to loss of habitat and exposure to pesticides.
Pesticides are present all around us - from the flowers in our gardens, to our meals, our soaps and our swimming pools.
Insecticides are generally the most toxic pesticides, at least in terms of direct, short-term effects, according to the Pesticide Action Network.
Particularly controversial are neonicotinoids, a family of insecticides used to control destructive crop pests. In 2013, the EU restricted their use after detecting environmentally harmful effects - particularly on bees.
But the debate still rages: Should neonicotinoids be completely banned? Or are they safe enough to continue to use?
The European Commission is preparing to review limits on the use of neonicotinoids set out in 2013. By fall this year, these pesticides could be under much tighter control.
Pesticides: useful for controlling unwanted damage, but harmful for biodiversityImage: picture alliance / Dinodia Photo
The neonicotinoids controversy
Several studies have shown these pesticides affect the brains and bodies of bees and other insects, changing their behavior, and reducing their fertility and lifespan.
As the risk these products pose to biodiversity became clear, the European Union in 2013 restricted the use of three neonicotinoids - clothianidin, thiamethoxam and imidacloprid.
Opponents of the ban have argued that evidence for the restrictions came from studies conducted under artificial exposure conditions, where the insects were exposed to higher levels of the pesticides that they would have been in the real world.
A new study financed by German chemical company Bayer and agribusiness giant Syngenta has now looked at the effect of neonicotinoids on bee colonies at exposure levels typical in the field.
But the companies argue that the results do not show the whole picture.
Life in the field
The study was carried out in the UK, Hungary and Germany, looking at three different bee species. In the first two countries, honeybee colonies' success at overwintering was reduced after exposure to crops treated with neonicotinoids.
Scientists have analyzed three species of bees in three different countriesImage: Paul Fisher
However, in Germany, no harmful effects on overwintering honeybees were found. That's partly because the UK and Hungary colonies were already in weaker health due to local diseases - and were feeding regularly on nearby oilseed rape crops treated with one of the neonicotinoid pesticides restricted by the EU.
"Up to 50 percent of their food came from crops treated with pesticides," Richard Pywell, co-author of the study, told DW.
This shows that despite the EU moratorium, there is a strong presence of these toxic substances in the fields, Pywell said.
It also upholds theories that neonicotinoids amount to an additional pressure on bees, which add up together into a cumulative negative effect.
However, Peter Campbell, head of research collaborations with Syngenta, told DW that researchers have only published the negative effects - while the findings also show potential beneficial ones.
"The results are much more complex than the simplistic conclusion the researchers have presented," Campbell said.
Bees' future may depend on upcoming political decisionsImage: Paul Fisher
Economics vs. the environment
The European Commission plans to revise the ban on neonicotinoids to prevent them from being used in any outdoor space, limiting them to greenhouses, Anca Paduraru, a spokesperson for Health and Food Safety at the European Commission, told DW.
The European Commission will present the revised regulation mid-July to be approved by member states, and is hoping for a resolution by the end of November.
However, recent debate over the herbicide glyphosate has shown such processes tend to take longer than planned - particularly if large member states such as Germany drag their feet.
Experts fear Germany may prioritize the economic advantages of the pesticides over their environmental impact.
Pywell said he wouldn't give a personal opinion on the controversial issue. "We are independent scientists and it is not our role to make political decisions," he commented.
However, he highlighted the need for greater consistency between regulations among different EU countries.
All about the birds and the bees...
All they want to do is feed on sweet nectar or other delicacies. But at the same time, they pollinate flowers and thus enable plants to reproduce. There's more to these little creatures than meets the eye.
Image: picture-alliance/dpa/P. Pleul
As sweet as honey
They are the pollination super stars! Honeybees account for about 80 percent of all pollination by insects. They visit a large variety of plants, collecting pollen and nectar taking it back to their hive. Each hive can collect about 66 pounds of pollen every year. As well as the honeybees, there are several thousand wild bee species. Most of those live a solitary life, not in hives.
Image: picture-alliance/dpa/P. Pleul
The humble bumblebee
They are bigger and hairier than honeybees, but just as useful: bumblebees also feed on floral nectar, using their long hairy tongues to collect the delicious liquid. Bumblebees are social animals like honeybees, but form much smaller colonies of only about 50 to 600 individuals.
Wasps have a bad reputation and the vast majority of wasp species play no role in pollination. That is because wasps have a smooth body without hairs, and pollen doesn't stick to them. Pollen wasps are different, though. They collect pollen and nectar inside their throats and feed their young with it.
Image: Colourbox
Just a busy bee?
These little creatures try to look dangerous by imitating the coloring of bees and wasps - but they are harmless and cannot sting. They are often seen hovering above flowers. The adults love nectar and pollen and are important pollinators. Hoverfly larvae are also useful: they feed on aphids and thus help with pest control.
Image: picture alliance/H. Bäsemann
To bee, or not to bee
They look a bit like a cross between a fly and a bee, hence their name. Bee flies can grow to up to four centimeters. They live in many parts of the world, but are most diverse in the tropics and subtropics. Adult bee flies love pollen and nectar; their larvae, though, feed on the eggs or larvae of other insects.
There are more than 18,000 species of butterflies, and most of them are brightly coloured. With their long, thin legs and relatively small bodies, they cannot carry as much pollen as bees. Still, they do a good job pollinating plants. Unlike bees, butterflies can see red which attracts them to different blooms than bees.
Image: MEHR
A help or a hindrance?
Moths are less colourful than butterflies, but they still belong to the same family. Moths fly at night. That's why they do not need bright colours. But they also feed on flowering plants. Some moths, and especially their caterpillars, are major agricultural pests, though.
Image: picture-alliance/Arco Images/J. Fieber
Don't beetle about the bush
Did you know that beetles also play a role in pollination? Some of them do, such as the flower scarab, also called flower beetle. As the name suggest, they visit flowers for pollen and nectar. There are around 4,000 species. One is the green rose chafer (photo).
Image: picture-alliance/blickwinkel/J. Fieber
In the blink of an eye
It is not only insects that do the pollinator's job - there are birds on duty as well. Especially birds with long slim bills like hummingbirds carry pollen from one flower to the next when feeding on nectar. Some species of plants have even evolved to produce flowers that appear especially attractive to hummingbirds.
Image: CC BY 2.0: KevinCole/flickr.com
Sun worshipper
Some other birds belonging to the passerine group also appreciate floral nectar. Take this Seychelles sunbird. Its long, slender bill shows that it is specialized on drinking from flower blossoms. This species is especially fond of hibiscus flowers.
Image: picture-alliance/blickwinkel/M. Woike
Creature of the night?
Bats - including their larger relatives, the fruit bats - play an important role in plant distribution and reproduction. While some bat species prefer insects, others feed on fruit or on nectar. When they drink nectar with their long tongues, they transfer pollen from one blossom to the next.
A creature that nose pollen
In Madagascar, primates like this mouse lemur pollinate flowers and are even essential to the reproduction of some tree species. They stick their noses into the flowers to drink nectar, and pollen collects on their snouts.
Image: Imago
Scaling up
Yes, there are even some species of lizard and snake that help with pollination. Researchers found that, especially on islands, lizards are important pollinators. They suspect that lizards have fewer predators on islands and are therefore more numerous. On these islands they can roam around more freely and expand their diet to nectar, pollen and fruit.
