photo of bee landing on oilseed rape flower

Bees and neonicotinoids: the problem

Find out how the use of neonicotinoid pesticides in growing our crops is contributing to the decline of wild bees.
  Published:  26 Jul 2017    |      5 minute read

Since 1900 we've lost around 13 species of bee in the UK alone, and a further 35 are at risk. A number of factors are responsible for the decline of bees. Find out why bees and neonicotinoids are such a controversial topic and what part pesticides play in the decline of our bee populations.

From bumblebees to solitary bees, we rely on each species to help pollinate our plants and crops.

But bees are in trouble. Loss of habitat and climate change are key factors. But pesticides are thought to be playing a huge part in the critical decline of our bee populations. And there's overwhelming evidence that a particular type of pesticide - known as neonicotinoids or neonics - is doing a lot of damage.

How neonics affect bees

Neonics are systemic pesticides used on plants. This means they are absorbed into every part of a plant – from the roots and stem, to leaves and flowers. When a bee feeds on pollen or nectar containing these chemicals, the neonic can damage its nervous system and motor function. This will affect the bee's feeding, navigation, foraging and reproduction.

Impacts of neonics on wildlife and the wider environment

New evidence shows that these pesticides aren’t only found on the crops they’re intended for. High levels of neonics are being detected on wildflowers and hedgerows around fields of treated crops. And this means the bees can’t escape them.

Other wildlife is also at risk. For example, it’s been shown that neonic seed treatments are washed off by rain and contaminate soils and water. Neonics have been found to affect earthworms, which are essential for keeping our soil healthy.

Neonics and the EU ban

In 2013 three of these pesticides were restricted across the EU following a vote of European member states. The UK vigorously opposed the move, despite the scientific evidence that these chemicals posed a “high acute risk” to honeybees.

Since then stronger evidence linking neonicotinoids with bee decline – and the decline of other wildlife – has emerged. And the European Commission is now proposing that the restrictions be extended to all outdoor crops.

Environment Secretary Michael Gove announced UK support for a neonicotinoid ban, recognising that the science is stacking up against them.

The extension to all crops is needed because evidence now shows that neonicotinoids contaminate the environment and can end up in wildflowers or water.

The EU will hold a vote on whether to strengthen the ban in the light of new research. Following Michael Gove’s announcement we expect the UK to vote for the tougher restrictions then keep them in place after we leave the EU.

A recent survey found that 81% of the British public want the government to maintain the EU ban on bee-harming pesticides.

As the UK heads for Brexit, we’ll be pushing our government to commit to tough environmental legislation to protect wildlife - and not to give in to pesticide industry lobbying.

Reasons for a ban on neonics

1. Neonics harm bees (and other wildlife)

Compelling scientific evidence includes research from both laboratory studies and field trials, such as:

  • In June 2014 a global study involving 29 scientists and over 1,000 papers by the Global Task Force on Systemic Pesticides concluded that neonics “are causing significant damage to a wide range of beneficial invertebrate species and are a key factor in the decline of bees”.
  • In April 2015, the highly respected European Academies Science Advisory Council (PDF) said there is clear scientific evidence for sub-lethal effects on bees and other pollinators exposed to very low levels of neonicotinoids over extended periods.
  • A study by Newcastle University, published in April 2015, found that bees preferred to feed on solutions containing neonics. It concluded that treating flowering crops with commonly used neonics “presents a sizeable hazard to foraging bees”.
  • Field trials in Sweden found the use of neonics-treated seeds “has negative effects on wild bees, with potential negative effects on populations".
  • In 2016 the Centre for Ecology and Hydrology published an 18-year study that showed a correlation between neonic use and the decline of wild bees.
  • Evidence is growing that neonics may also be affecting butterflies. Evidence includes a study by the University of Stirling which showed that the decline of 15 out of 17 butterfly species monitored correlated with neonic use.
Bee next to a poppy flower

2. Bees are being exposed to more neonics than previously thought

A wildflower study found that flowers like poppies growing next to fields of crops treated with neonics contain high levels of these pesticides. Poppies and other wildflowers are an important source of food for bees.

Meanwhile research from Canada found that neonics remain much longer than expected in soil dust, and that the dust is dispersed widely, potentially increasing bees' exposure to them.

In 2016 the European Food Safety Authority concluded that there is a high risk to bees exposed to the neonicotinoid clothianidin via dust drift when treated cereal crops like wheat are sown. There is also a high risk from exposure via flowering crops grown after a treated crop such as winter wheat. This is because of the persistence of the chemical in the soil.

Research is showing neonics remain in the environment and are found a long way from where they were used. So there is now a strong case to extend existing restrictions - which only apply to some crops like oilseed rape - to all crops such as wheat.

Photo of honeybees returning to hive

3. There is a lack of evidence that neonics help farmers

The National Farmers Union (NFU) says there are crop losses due to damage from cabbage stem flea beetle (CSFB), resulting from the restrictions on neonicotinoids.

The NFU persuaded the government to allow oilseed rape treated with 2 of the restricted pesticides to be planted in parts of the country in 2015. But when it tried to do the same in 2016 the government rejected the application, keeping our oilseed rape fields free of the banned pesticides.

In fact, when neonics could not be used - in 2015 - yields for oilseed rape were higher than in 2014 and above the 10-year average. Although yields in 2016 were looking to be below the 5-year average, this was due to a number of factors including weather, with loss to pests being only one.

Some farmers will have suffered crop losses because of pests, but these could have happened even with neonic-treated seeds. In fact, one study found no consistent benefit on crop yield from using treated seeds.

What we do have evidence for is that insect pollination enhances oilseed rape yields - and has also been found to increase the value of 2 British apple varieties by £37m a year.

Now new research suggests that neonics could be damaging food production. Apples pollinated by bumblebees exposed to neonics were lower quality than neonic-free bumblebees

We found that bees exposed to pesticides returned from apple flowers with less pollen than bees in the control group. This suggests that bumblebees exposed to pesticides must somehow behave differently on flowers.

Dr Mike Garratt, University of Reading

4. There are alternative ways of controlling pests

The NFU says that farmers will be forced to use more of other pesticides such as pyrethroids if the neonic ban continues. It's true that some farmers have used more of these pesticides, but we believe there is no need to.

Research for Friends of the Earth found that there are effective non-chemical means of control, such as encouraging natural predators that eat the pests. Measures to help natural predators can be good for pollinators too. This includes things such as planting wildflower margins and hedgerows.

Pesticide use can also be reduced if crops are carefully monitored for pests before a decision is taken to use a chemical. If sprays are only used as a last resort the pests are less likely to develop resistance too.

Farmers need more support from the government and the farming industry to develop other promising methods of pest control. Approaches could include companion cropping, which may help draw pests away from the crop.

Help save Britain's bees. Donate today for your Bee Saver Kit.

Help save Britain's bees. Donate today for your Bee Saver Kit.