In 2013, the EU Commission issued restrictions on certain uses of three insecticidal compounds from a group called neonicotinoids in certain crops due to concerns related to their bee safety. How has the ban impacted bees and crops? The Bayer Bee Care Center in Monheim takes stock.

"Oilseed rape used to be our biggest break crop and a very important part of the rotation but now we are down to zero," says Tom Bradshaw who farms 1,350 hectares near Colchester, a town in the South East of England. "This year we stopped growing it because it was no longer economical.

Not with the neonic seed treatment removed." Tom used to harvest nearly four tonnes of rape per hectare but in the first two years after the ban he lost almost half of his rape yield, partially contributed to a pest called cabbage stem flea beetle (Psylliodes chrysocephalus). And Tom is not alone. Since the ban on neonicotinoids, UK farmers have had huge problems in regions where the beetle is prevalent.

In some areas near London two out of three fields were completely lost. Like Tom, many of the farmers have given up growing oilseed rape altogether. Three years into the ban, UK oilseed rape production is down by 17 percent.

The question is: Was it worth it? Has the ban improved the situation of UK bees? "No," says Dr Julian Little, Bayer Bee Care spokesman in the UK.

"In the season before the ban, the UK had some of the lowest honey bee colony overwintering losses since they started recording them in the early 2000s. Then came the ban, and after this, bee losses have become great again. The fact that there was no visible trend towards an improvement seen, after the ban, makes it obvious that there must be factors, other than neonicotinoids, impacting the health of bees."

Beware of the destructive Varroa
One major factor in honey bee colony losses is a parasitic mite called Varroa destructor. A wealth of data shows that high colony losses are mostly correlated with the degree of Varroa infestation in the hive. This correlation is obvious in monitoring data from various countries of Europe and North America and also from a survey conducted on behalf of the EU Commission, published in 2013.

In this, EU beekeepers and EU Member State Reference Laboratories for Bee Health were asked what they thought were the main causes of colony losses and clearly pointed at diseases and Varroa (and the related viruses they transmit). Another key factor impacting the survival and vitality of honey bee colonies is their access to food: Bees need an abundance and diversity of flowers from which to collect nectar and pollen throughout the season.

Unfortunately, the wild flowers that used to make field seams and country lanes so pretty, have largely disappeared, leaving bees with less choice and availability at certain times of the year. If many UK farmers replace oilseed rape with less or even non-bee attractive crops such as spring oats or barley, another important food source for honey bees will dwindle.

"Oilseed rape is a source of pollen early in the season for bees," says Tom Bradshaw. "I am worried about what will happen to the honey bees in Europe if the availability of an important food source like oilseed rape goes down." Suspension of neonicotinoids use has not led to improvement of bee health On the other hand, most available monitoring data shows no correlation between honey bee colony losses and agricultural intensity, nor is there any clear spatial pattern seen that would suggest the involvement of pesticide exposure or agriculture in general as a key factor impacting bee health.

There are for instance data from Switzerland which confirm that colony losses are the same, independent of the altitude - which means the same loss rates whether bee colonies may be exposed to intensive agriculture with neonicotinoids, or not. Likewise, in countries where uses of neonicotinoids have already been suspended before the bans on EU level, like France, Italy, or Germany, no sudden improvement of bee health has been documented.

In contrast, for instance in canola-growing regions in Western Canada, neonicotinoids have regularly and intensively been applied in bee-attractive crops. As a result, honey bee colonies have regularly been exposed to these when foraging and for managed pollination. Here, colony numbers have been rising for many years and bee health is reported to be good. "I am worried about what will happen to the honey bees in Europe if the availability of an important food source like oilseed rape goes down."

Suspension of neonicotinoids use has not led to improvement of bee health
On the other hand, most available monitoring data shows no correlation between honey bee colony losses and agricultural intensity, nor is there any clear spatial pattern seen that would suggest the involvement of pesticide exposure or agriculture in general as a key factor impacting bee health.

There are for instance data from Switzerland which confirm that colony losses are the same, independent of the altitude - which means the same loss rates whether bee colonies may be exposed to intensive agriculture with neonicotinoids, or not. Likewise, in countries where uses of neonicotinoids have already been suspended before the bans on EU level, like France, Italy, or Germany, no sudden improvement of bee health has been documented.

In contrast, for instance in canola-growing regions in Western Canada, neonicotinoids have regularly and intensively been applied in bee-attractive crops. As a result, honey bee colonies have regularly been exposed to these when foraging and for managed pollination. Here, colony numbers have been rising for many years and bee health is reported to be good.

How the farmers try to cope
Farmers need to look after their crops as best they can; and once they have planted them, they need to control the pests. So instead of using neonicotinoids, farmers all over Europe have gone back to using pyrethroids, an older class of insecticides. It is less effective, so you need to use more of it:

"As a result, the number of pesticide applications in the UK has increased significantly," says Tom and highlights another drawback: "Whereas neonics are used as seed treatments, so they are in the ground and exposure of most organisms in the environment is limited, most alternative products need to be sprayed over the crop.

Overall, if we look at the exposure of the environment as a whole, we would be better off with the neonicotinoids". In Europe too, there are regions, where neonicotinoids could actually be used during the past three years because farmers obtained an emergency authorization (derogation) from their respective country for a limited use of some products in order to save certain crops.

One such country is Romania where wide areas are infested with the maize leaf weevil (Tanymecus dilaticollis). In affected areas, neonicotinoids are the only control solution and there is no alternative to treating the seeds. If you wait until the crop has grown, it is too late: The plants are attacked in their early developing stages and without protection they often fail to reach the stage when spray application is possible.

So, Romanian farmers were granted a so-called derogation - an exemption from the suspension. "And it works well," says Ana Gheorghiu, Bayer Bee Care spokesperson in Romania. "The farmers and beekeepers in Romania have very good relationships, and by promoting the use of a technology to reduce insecticidal dust emissions when sowing treated seeds, Bayer has been helping farmers to keep our pollinators safe."

What does Bayer do?
All over Europe, Bayer is committed to safeguarding bee health, promoting stewardship and the safe use of its products. In addition, Bayer is dedicated to supporting agriculture: "Whether farmers have access to neonicotinoids or not," says spokesman Dr Julian Little, "they need to control the pests.

So we offer them old and new chemistry, information about which crop to grow, and the best timing for planting and spraying. We work closely with research institutes to give them the best advice possible in all of these areas." Furthermore, Bayer is for instance cooperating with others in the crop protection industry to provide European farmers and beekeepers in a number of countries with an app to help them cooperate and communicate more easily.

The farmer identifies his farm on the map and announces where and when he will apply a treatment. Then the app sends a message to registered beekeepers in the vicinity. Travelling beekeepers can also register with the app and send a message to the farmers to announce their arrival and where they have positioned their beehives.

Respecting facts and figures
In 2017, the neonicotinoid restrictions are due to be re evaluated by the EU Commission. Bayer's view on the matter is very clear: "Whether a product can or cannot be used should be based on sound science," says Dr Little. "It is almost as if in the past years, these decisions were based on who shouts loudest. Assumptions were made that the ban would help bees, even if there was not sufficient scientific evidence to prove that neonicotinoid seed treatments were causing harm to bees under practical conditions. Neither did the EU have reliable information on the socioeconomic consequences of the ban."

Further research and assessments are now underway to further support evidence based decision-taking. Bayer has been conducting studies such as the large-scale field study in Mecklenburg-Vorpommern in Northern Germany to determine the potential impact of neonicotinoid seed treatment in oilseed rape on bees. The now published data showed no effects of oilseed rape grown from seeds treated with clothianidin on wild bees, bumblebees and honey bees.

And most recently, a study published by the Humboldt Forum for Food and Agriculture has shown what the ban so far has meant for European farmers and the environment. "With this increased knowledge base on hand, hopefully the EU Commission will take their next neonicotinoid decision based on realism, transparency and scientific evidence," adds Julian.

Last, but clearly not least, such an objective approach would be in the interest of European consumers. They expect farmers to be able to produce safe, high quality, affordable food. But without the right tools this will be difficult and consumers will be the ones to pay the price - literally. And while some of the wealthier European countries would "merely" be inconvenienced by rising food prices, in countries like Romania, the ban would have a heavy social impact, says spokeswoman Ana Gheorghiu:

"A ban of neonicotinoids in Romania would mean the loss of 1.2 million tonnes of corn. And it would lead to more people abandoning their villages to look for jobs elsewhere, leaving their children to be raised by the grandparents. That is why a political decision to reverse the ban is important for us. I try to be optimistic."