Last week I went to a British Library evening event on pollinators and pesticides, which took a look at whether pesticides are the real culprit for the decline in bee numbers. The event only cost £5 and it included free wine and chocolate honeycomb covered sweets. Score!
Oh, and it had some very good speakers too, which is why I was there of course. Our chair was BBC Presenter and hobby beekeeper Bill Turnbull, with speakers Dr David Aston (Chairman, The British Beekeepers Association), Dr. Peter Campbell (Senior Environmental Specialist, Syngenta) and Dr. Lynn Dicks (Postdoctoral Research Associate, University of Cambridge).
Talk Science events are held by the British Library for researchers from academia and industry, policy makers, research funders, publishers and all those with a stake in science. You can follow the Science team on Twitter @ScienceBL, event hash tag #TalkScience. The team has since done a British Library science blog post on the event, which has a photo of me and a link to my blog – thanks guys!
This particular talk was being filmed for a Horizon programme due to be broadcast on Friday 2nd August, so you may spot me in the audience if you watch it! Bill Turnbull began by saying that he wanted “an informative rather than combative debate” – a sign that feelings would be running high.
Each panellist began by saying a little bit about themselves and their work. David was speaking on behalf of honey bees and identified weather and forage availability (both quality and quantity) as two of the biggest problems facing them.
According to David, 30 kilos of pollen are required by an average honeybee colony during a year (the equivalent of 15 bags of sugar) and 120 kilograms of nectar – just to survive, before the beekeeper comes along and removes any surplus honey.
He reminded us that beekeeping now requires a high degree of technical competence. Bees are wild animals, not domesticated creatures like sheep and cattle. They have their own minds and won’t always do what beekeepers want them to!
David has seen no evidence of harm to honey bees in the UK from neonicotinoids. He is worried about what alternative products will be used after the ban comes in.
Lynn has expertise in ecology and conservation. She put bees as pollinators in the food chain into context with a few facts:
- Bees are important pollinators because they consume pollen both as developing larvae and as adults (unusual in the insect world)
- There are around 256 species of wild bees living in the UK: just one species of honey bee, 24 species of bumble bees… and the rest are solitary bees.
- Hoverflies are important pollinators too. In some parts of Scotland, hoverflies are the most frequent pollinator visitors to flowers. There are 250 odd species of hoverflies in the UK and they eat pollen as adults. Of course there are also the wasps, beetles, butterflies and moths busy doing their thing too.
We have a good idea that wild bees have declined in diversity in the UK, but we don’t know by how much. Research published in Science journal in 2006 provided the first data available on bee numbers. However, we still don’t know how many individuals there are. We do have numbers for butterflies and moths – they are suffering ongoing declines.
For Lynn, the main problems are loss of flowers, loss of habitat, possibly climate change and diseases – “multiple, interacting threats”. She has four suggestions to help bees:
- Farmers should start treating pollination as an essential agricultural input to invest in and think about how to manage their landscape for pollinators
- We should protect habitat, both in urban and country areas
- Reduce use of pesticides overall (use is actually going up slightly right now)
- Find out how many wild bees and hoverflies there are. Hard as that might sound, Lynn says there are good techniques available which don’t cost much.
EDIT: Philip Strange, a scientist and writer, kindly left me a comment below with a link to a post by Lynn where she expands further on these points: Action for pollinators: things we can all agree on.
Peter was last to speak. No-one booed when he introduced himself as an environmental risk assessment scientist at Syngenta, a manufacturer and seller of pesticides, but I imagine some bristled a bit.
Obviously Peter has a particular angle to take on behalf of Syngenta, which is that neonicotinoid research studies in the past two years have mostly been carried out in labs rather than the field. Syngenta have been doing many field trials on honey bees themselves, which so far have found no risk to bees when the neonics are used properly.
They are currently doing a project on developing flowering margins, particularly on cereal farms, and have developed flowering mixes for field edges. The mixes have led to species which had disappeared previously returning. “Habitat is everything with wild bees… and varroa in the case of honeybees” Peter said.
Things got spiky between the panel, particularly Peter and Lynn, as Bill came onto the issue of neonicotinoids. He brought up a study which had found that neonicotinoids left the directional memory of honey bees unaffected, but did have an effect on the landscape memory of bees trying to find their way home.
Peter’s response to this was that the study gave an unnaturally high dosage to bees, much higher than they would come across in the field. An experienced beekeeper in the audience agreed with him, using the analogy that experiments done so far seem to be like locking dogs in a garage with a running car for 24 hours and then blaming the internal combustion engine for their deaths. However Syngenta are doing work this year with RFID tags to try and see if landscape memory is a real issue.
David’s worry is that the neonicotinoids ban could lead to greater risk of exposure to other pesticides which farmers will turn to instead. Neonics were originally seen to be an environmental improvement on previous treatments. Peter added that oil seed rape may not be such a profitable crop without neonics and farmers may switch to growing cereals instead – but Lynn disagreed with this theory.
Lynn would like to see farmers become more reliant on integrated pest management (which the National Bee Unit inspectors recommends beekeepers carry out too). This involves using a range of methods during the year to keep pests at bay, rather than relying on one particular method of treatment.
According to Lynn, using systemic neonics in crop seeds means that farmers are no longer treating if and when pest attack is seen, but in advance of it happening – sounds good in theory but is not so great for the environment. Peter’s counter argument to this was that seed treatment allows farmers to target pests very carefully, and leads to less dosing of the field environment as a whole.
“Is the European Commission ban worthwhile?” asked Bill.
The background to this is of course the European Commission’s two-year moratorium on the use of three neonicotinoid insecticides on “bee attractive crops”, following risk assessment reports from the European Food Standards Agency.
Lynn – the ban is a good place to start but two years is not long enough to assess its impact. However, scientists can do more analysis within the next two years to gather data on the possible effects of neonics. She pointed out that whilst the case for an effect on honeybees is uncertain so far, lab studies using realistic doses have found a dramatic reduction in bumble bee queen production.
She believes we don’t yet know how realistic lab studies are, but if there is a risk it’s best for the EC to take a precautionary approach until we know more. This does mean making a subjective judgement. Two years gives some time for scientists to gather baseline data on bee numbers. A fantastic study named ‘Status and Trends of European Pollinators‘ (STEP) is currently going on to document the nature and extent of European pollinator declines. Knowing how many pollinators there are is necessary to tell if numbers go up or down as a result of this ban or any future ones.
Moving on to less controversial subjects, Bill went on to ask “Why is weather such a problem now?”
David replied that our weather today is a reflection of carbon dioxide levels twenty years ago. We are having increasingly extreme weather swings, with 2012 bringing unusually long periods of both wet and dry weather in the UK. In early 2012 water companies were running campaigns to save water, only to be followed by one of the wettest springs on record, with flooding in many parts of the country. Long periods of wet, cold weather can cause problems with unmated virgin queens.
“Colony collapse disorder. Is it here in Britain?” – Bill.
David told the audience that the general BBKA view is CCD doesn’t occur in this country. Colonies do collapse, but not in the same way as reported in the US.
And finally, Bill’s last question was “What does the future hold for bees? Are you feeling optimistic?”
David – To be a beekeeper, you’ve got to be optimistic! We can all do things to improve forage and nectar sources. Weather and a lack of forage are critical factors for most insect species.
Lynn – optimistic about the huge amount of interest in pollinators and the number of young scientists being trained. More funding money is becoming available from governments. During the past 20-30 years insects have not been looked after well – this may be starting to change.
Peter – we need biodiversity. Helping pollinators is all about habitat. Environmental subsidies will really help pollinators going forward. We also need more research into practical solutions, such as fighting varroa – the biggest problem facing honey bees now.
Not being a scientist or farmer myself, and without having read through much of the current research, it was hard for me to form an opinion as to whom was right – Lynn that neonics pose serious risks to bumble bees based on the research, or Peter that lab studies are too unrealistic and do not reflect field conditions.
Knowing that Peter must defend Syngenta’s interests as part of his job does make me skeptical. It’s easy for Syngenta to say that lab tests don’t relate to field doses, knowing full well that it’s very difficult to carry out tests in the field because bees forage over such large distances. On the other hand, I agree with Peter that providing good bee-friendly forage and researching solutions to varroa is very important – even though I suspect he may be bringing up these factors to distract from the neonics issues!
What do you think, was the EC right to put the ban in place?