On Monday 6th October I went to the fourth annual London Honey Show, an event celebrating London’s honey and bees in general. As well as a honey tasting competition, there are stalls selling food, beekeeping books and beauty products, plus expert speakers doing short talks. This year’s show was a lot of fun, especially as I knew several people there and warming honey cocktails & mead samples were on offer.
Dave Goulson’s talk
Here are some notes from the talk by Dave Goulson, the second speaker. Dave is well known as a Biology Professor at the University of Sussex, writer of books A Sting in the Tale and A Buzz in the Meadow and founder of the Bumblebee Conservation Trust in 2006, a charity which now has 8,000 members.
Speaking to a room of honey fans, Dave wanted to remind us that honeybees are not the only bees! There are an incredible 22,000 known species of bees worldwide, including around 250 species of bumblebee.
He gave a quick explanation of the life cycle of bumblebees to us. Emerging from their winter hibernations, bumblebee queens visit pussywillow and lumpwort flowers in early spring. They look for ex-mouse or vole cavities, preferably with some soft bedding material already inside. After laying their precious first eggs, they sit over them like birds on their nests, shivering their muscles to keep the eggs warm. So cute!
We think bumbles first originated east of the Himalayas about 30 million years ago. They have adapted to live in cold weather and tend to be scarce in warm areas like the Mediterranean. Bumbles can keep their body temperature an incredible 30ºC higher than the surrounding air temperature, allowing them to fly in the Arctic in temperatures below freezing. Dave showed us a photo he took of a buff-tailed bumblebee flying in January, feeding on Mahonia amongst the snow.
The downside to this ability to stay warm is that it takes them huge amounts of energy to stay in the air. Bumblebees need LOTS of flowers. This appetite and their ability to do buzz pollination makes them major pollinators of crops like oilseed rape, field beans, tomatoes, peppers, raspberries and strawberries. I took the photo of the bumblebee below on chinese anemone and seem to remember she was doing some buzz pollination, intensely vibrating her muscles to shake the flower and release extra pollen from its anthers.
Unfortunately bumblebees are not doing as well as they used to be. For instance, as recently as the 1950s the great yellow bumblebee used to be found in many different sites in England, Wales and Scotland, from Scotland’s Orkney Islands to England’s most southerly county, Cornwall. It is now confined to Orkney, the Hebrides and the northerly coast of Scotland. Why?
Dave gave us his opinions on the reasons some British bumblebees, such as the great yellow bumblebee and the short-haired bumblebee, have declined in their range:
1. Changes to farming
England lost 98% of its hay meadows and chalk downland during the 20th century. Like the great yellow bumblebee, Corncrakes, birds which used to nest in hay meadows all over the UK, now live only in remote corners of Scotland where farming has changed relatively little.
The commercial trade in bumblebees shipped for pollination has spread diseases such as nosema ceranae between bumblebee populations. This has happened in Chile, where accidental releases of European bumblebees being used for pollination have spread disease to native bumbles there.
Dave begged us not to buy bumblebee colonies from garden centres. They are supplied from factory reared colonies from Europe used for tomato pollination, and are often full of parasites and diseases. Read more about this issue at Buzzaboutbees.net’s Bumblebees for sale? page.
3. Neonicotionoids (Neonics)
For this part I’ve added to my notes using the chapter ‘The Disappearing Bees’ in Dave’s recent book A Buzz in the Meadow. Introduced to the world in the mid-1990s, this type of insecticide works by attacking the nervous system and brain of insects. Their advantage is meant to be that they can be applied as a seed dressing before the crop is sown, which the growing seedling then absorbs, spreading the chemical throughout the plant. This prevents the farmer having to spray insecticides several times as plants develop.
The trouble with a insecticide present in all parts of the plant is that nectar and pollen produced by the plant contains the insecticide too. Each time a pollinator visits the plant, they consume a small amount of the neonic. This stuff is highly toxic – just 1 teaspoon of neonicintinoids is enough to kill over a billion bumbles.
Research carried out by Dave and his team, published in the journal Nature, found that bumblebee nests fed on nectar and pollen mixed with very low field-like concentrations of the neonic Imidaclaoprid (used to treat oilseed rape seeds) produced 85% less queens over a season than nests fed with clean nectar and pollen. The control nests fed with untreated food produced an average of about thirteen new queens each, the nests fed with treated food an average of just two.
Disturbingly, most of the neonic seed chemical coatings, between 80-98%, end up not in the plants themselves but in the soil. Once in the soil, most published estimates of the half-life of neonics are anywhere between 200 to 6,000 days, depending on soil type and conditions. They are also water soluble. So these chemicals are everywhere in our soil and waterways, having who knows what effect on the insects within them. Please, please don’t add to the chemicals in our world by treating your lawns and garden plants with insecticides.
Don’t buy “hideous annual bedding plants – an absolute travesty”. They often have no scent, no nectar and some no pollen. Instead, grow perennial cottage garden type flowers. Dave’s favourite is viper’s bugloss.
If you have no garden, badger your local council to stop wasting your money on mowing verges and removing habitat for bees.
I’ve done some other posts on books/talks by Dave:
- Book review: A Sting in the Tale by Dave Goulson (2013)
- A future without bees: A talk at the Southbank Centre (2013)
And Emma’s done a very entertaining post on the London Honey Show with lots of photos:
Below is Dave speaking in front of a photo of Toby, a army-trained sniffer dog who helped one of Dave’s Phd students hunt for bumblebee nests. You can read about him in Dave’s book A Sting in the Tale.
Thanks for posting this. I too am a fan of Dave Goulson
Thanks Ann. He is doing such good work to save bumbles.
I would love to hear Goulson speak. I had “A Buzz in the Meadow” ordered on Amazon to arrive immediately it was published. I was not disappointed! Amelia
I am enjoying it, though of course some chapters are very upsetting, such as the research on neonics and inbreeding. I’m sure your garden plays an important part in preserving local bee populations.
I too am a big fan of Dave Goulson, his book A Sting in the Tail, and the Bumblebee Conservation Trust he founded. Pleased you had the opportunity to hear him speak. Thanks for this account.
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Not only the Insects but more seriously the trace elements of the Neonicotinoids from the ground, groundwater and Maize Corn and Rape oils are building up in OUR systems at the top of the food chain and are being linked to the increased incidence of early Alzheimers.
Two other problems with the coated Maize corn seed are, firstly the shaking of large seeds when drilled give off a dust which drifts into surrounding hedgerows killing other insects, and secondly though the bees get no nectar from the Maize, they feed their young with contaminated pollen from the tassels which affects their ability to navigate and return to the hive or nest.
I’m sure you’re right, we’re not only hurting insects but ourselves. Disturbing to think these chemicals are all around us.
It would be good if Jonathan could provide a reference to the science behind his claim that the neonics are leading to an increase in incidence of early Alzheimer’s Disease.
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Thanks for sharing his talk, depressing as it is. I’m sure we are in the same bumblebee mess over here. I’ve added those books to my “to read” list.
Although a lot of issues covered in Dave’s books are sad, I should add there’s a lot of humour and fascinating facts about bumbles too. I think you’ll enjoy reading them.
Great talk summary!
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Thanks for the summary, Emily, very interesting. It’s good to see the different risks to bumblebees laid out clearly. Have you seen this post from Dave Goulson which contains some important support for the present ban on neonics: http://splash.sussex.ac.uk/blog/for/dg229/2014/10/10/are-crops-being-devastated-without-neonicotinoid-protection
Thanks for the link, I read the post earlier today on the London beekeepers Facebook group. Amazing that anyone could claim badgers are the main danger bees face! Seems like a cynical attempt to justify the badger culls to me.
One of my bee club mentors taught me the slogan “don’t eat what they spray and they won’t spray it any more!”…I was wishy washy over organic produce until I kept bees and realized how heavily so many fruits and veggies are sprayed. On the basis of seeing what the local blueberry farmers spray (everything you can think of, including neonics at least 4 times a season), I refuse now to eat anything but organic blueberries! Most berry crops have horrendous spray regimes. David is right about Viper’s Bugloss (Echium vulgare) and I find Catmint (not catnip) is an even bigger favourite with my honey bees. They also love spring flowering heather, fennel, Rosebay Willowherb (Epilobium) and Phacelia. And in my yard, Borage is a bumblebee magnet!
I will look out for organic blueberries now, thanks for the warning. Ours love borage and rosebay willow-herb too.
Thank you Philip —-Rodrigues, K. J. A., et al. “Behavioral and biochemical effects of neonicotinoid thiamethoxam on the cholinergic system in rats.” Ecotoxicology and environmental safety 73.1 (2010): 101-107.
also – the research of the Dutch toxicologist Hank Tennekes on residual pesticides in soil and groundwater affecting the feeding bird and raptors food chain.
My exact words were ‘are being linked to’ as more research is needed.
Though many research articles differentiate between insect and mammalian receptors to neoni cotinoids, It is very conceivable that like DDT, these lingering residues from different sources may build up and affect us mammals.
Incidentally badgers are a very big threat to bumble bees and will dig them up wherever found and in Sussex they are also being blamed for the serious lack of Hedgehogs to which they are also very partial..
Thanks for the references Jonathan.
I know badgers dig up bumble bee nests, but badgers and bumblebees have both survived together in this country for thousands of years. Unless we have an unprecedented number of badgers at the moment, I don’t see why they would suddenly be a problem. To ignore habitat destruction, lack of forage and insecticides being used all over the country and instead blame…. the badgers…. seems hugely unfair to me.
Thanks for the references Jonathan. As you say, there is some evidence that the neonics can affect mammalian brain in animal experiments but the relevance to their use as insecticides will depend on the concentrations needed to see an effect in these animal tests. Whatever the outcome, these experiments are a long way from Alzheimer’s disease.
I totally agree with you Emily that it is a very unfair comment in the article ,I had not looked at the context of the remark in the link before I wrote.
We do however have a lot of badgers round here and judging by the frequent roadkills ,cars are their main balancing factor. In their favour they also love wasp nests!
I’m glad you have lots of badgers around – hope they manage to escape the government culls. Eating wasp nests is very useful! They are plaguing our bees at the moment.
I to am a fan of Dave. I spotted the buzz in the meadow and started to read it thinking he could not captivate me again like the sting in the tail. I was wrong, it was brilliant. It’s the sort of book I finish and start thinking about who to lend it to straight away. I found the last sections of the buzz in the meadow were not comfortable to read at all, but it needed to be said and I’m glad he wrote it.
Definitely. Hope he’s working on the next one!
Another fan of Mr Goulson & his books. Thanks for the account of his talk and for provoking such an array of relevant and interesting comments and replies. We have made life so complicated with our interferences and ‘improvements’, sadly to our own detriment.
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Another Goulson fan here! A hero among bee keepers – he really is an expert!
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