More misinterpreted science - watch out for the spin-fest

[gavin]

Hi Folks

Yet another bit of science contributing to the overall picture of the effect of pesticides on bees. James Nieh's team in California.

Boil it all down and pare away all the spin and what do you get? Bees fed 24 ppb imidacloprid (that's 20+ times the exposure expected in the UK from seed treatment of oilseed rape) were temporarily affected. The effect was to make them less keen on lower concentrations of sugar. Less proboscis extension in trapped bees, less waggle dancing for the weaker sugar. The effect was measured 1 hour after treatment and, guess what, 24 hours after treatment the effect had gone. Just as would be predicted from the work that shows that imidacloprid has a half life in a bee of about 5 hrs.

All wrapped up in the usual hype and spun to within an inch of its life. The University of San Diego claims this 'sheds light' on one of the main culprits suspected to be behind recent bee declines.'

http://ucsdnews.ucsd.edu/pressreleases/commonly_used_pesticide_turns_honey_bees_into_pick y_eaters/

So, what this research seems to say is that if bees are exposed to much greater levels than are encountered in properly regulated agriculture, there is a temporary effect. The effect noted will *decrease* the propensity of the colony to forage on the dangerous flowers and presumably decrease the threat to the colony (obviously a good thing). Then the colony recovers quickly. This work just confirms that the way these compounds are used in the UK is OK, but over-dosing and over-use could be dangerous.

Let the spinning, campaigning, and piss-poor journalism commence .....

Gavin

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http://jeb.biologists.org/content/215/12/2022.abstract

A nicotinic acetylcholine receptor agonist affects honey bee sucrose responsiveness and decreases waggle dancing

Daren M. Eiri* and
James C. Nieh

A nicotinic acetylcholine receptor agonist, imidacloprid, impairs memory formation in honey bees and has general effects on foraging. However, little is known about how this agonist affects two specific aspects of foraging: sucrose responsiveness (SR) and waggle dancing (which recruits nestmates). Using lab and field experiments, we tested the effect of sublethal doses of imidacloprid on (1) bee SR with the proboscis extension response assay, and (2) free-flying foragers visiting and dancing for a sucrose feeder. Bees that ingested imidacloprid (0.21 or 2.16 ng bee–1) had higher sucrose response thresholds 1 h after treatment. Foragers that ingested imidacloprid also produced significantly fewer waggle dance circuits (10.5- and 4.5-fold fewer for 50% and 30% sucrose solutions, respectively) 24 h after treatment as compared with controls. However, there was no significant effect of imidacloprid on the sucrose concentrations that foragers collected at a feeder 24 h after treatment. Thus, imidacloprid temporarily increased the minimum sucrose concentration that foragers would accept (short time scale, 1 h after treatment) and reduced waggle dancing (longer time scale, 24 h after treatment). The effect of time suggests different neurological effects of imidacloprid resulting from the parent compound and its metabolites. Waggle dancing can significantly increase colony food intake, and thus a sublethal dose (0.21 ng bee–1, 24 p.p.b.) of this commonly used pesticide may impair colony fitness.

[Jon]

Thanks Gav. I read some of the newspaper reports but none of them mentioned the PPB. You need to be testing 1-5 PPB with Imidacloprid.
Why do they always test far higher levels such as in the Harvard Study?
I suspect it is that nothing is noted at lower levels
The other thing is that the lab tests are like the tests being done about 10 years ago.
I think one of the best ways forward is the RFID transmitter work with full colonies foraging in the open.

Did you see the picture of bees in this study. bear in mind the concept of the honeybee colony as a superorganism.

http://ucsdnews.ucsd.edu/pressreleas..._picky_eaters/

[gavin]

Yep, and the 'superorganism' part of this research suggests that the whole colony is fine.

Let's speculate. Let's imagine that there is a smaller but still detectable effect when you reduce the concentration to one twentieth. Unlikely, I know, but let's assume it to be true for now. Then bees flying out to the OSR fields come back a bit unwell. They are no longer interested in dilute sugar nectar, and don't feel up to doing a lot of waggle dancing. Their contribution to the overall colony effort declines. The colony isn't encouraged to visit those dangerous fields. Other bees going to sycamore and early hawthorn, plus the pears, late plums, dandelions, gorse, you name it, they are fine. They come back and dance vigorously. The colony switches to safe forage and hardly touch the stuff with the short-term slightly deleterious effects.

But the whole colony had been contaminated, you say! OK, but the effects were slight even for the bees that fed on the contaminated nectar and burned up a lot of it on their journeys to and from the dangerous fields. So it was diluted even more for the other bees. Once the automatic positive feedback for better forage sources kicks in it would be very diluted. No problem.

This is a self-regulating system. The effects were transitory for grossly over-contaminated bees. There are no alarm bells ringing here for bees in the UK as far as I am concerned. And we don't see colonies regularly ignoring fields of oilseed rape in favour of other sources out at the same time. Probably. As far as I can tell. Do correct me if you think otherwise.

G.

[Bumble]

From Jon's link

“Remarkably, bees that fed on the pesticide reduced the number of their waggle dances between fourfold and tenfold,” said Eiri. “And in some cases, the affected bees stopped dancing completely.”

Maybe the bees wouldn't have bothered passing on the information because they didn't like what they were being forced to eat?

[Stromnessbees]

Let's have a close look at how Gavin is twisting another study result:

...
The effect was to make them less keen on lower concentrations of sugar. Less proboscis extension in trapped bees, less waggle dancing for the weaker sugar. The effect was measured 1 hour after treatment and, guess what, 24 hours after treatment the effect had gone. Just as would be predicted from the work that shows that imidacloprid has a half life in a bee of about 5 hrs.

Gavin makes it sound as if all the effects had gone within 24 hours.
But they clearly haven't:

...
Bees that ingested imidacloprid (0.21 or 2.16 ng bee–1) had higher sucrose response thresholds 1 h after treatment. Foragers that ingested imidacloprid also produced significantly fewer waggle dance circuits (10.5- and 4.5-fold fewer for 50% and 30% sucrose solutions, respectively) 24 h after treatment as compared with controls. However, there was no significant effect of imidacloprid on the sucrose concentrations that foragers collected at a feeder 24 h after treatment. Thus, imidacloprid temporarily increased the minimum sucrose concentration that foragers would accept (short time scale, 1 h after treatment) and reduced waggle dancing (longer time scale, 24 h after treatment). The effect of time suggests different neurological effects of imidacloprid resulting from the parent compound and its metabolites.

It's even mentioned twice: there is a longer lasting effect, be it from imidacloprid itself or its metabolites.
All the other talk about the colony regulating the effect of the toxic substance by taking in less of it is far fetched, as parts of the study results have been selectively ignored by Gavin.


And did anybody else here notice that Gavin was economical with the truth again?
Jon?
Nellie?

Where's your scientific scrutiny?

[Neils]

Funny, when you read the bits you didn't highlight it appears to match what Gavin said. Even when you read the bits you did highlight but use the rest as context it still appears to match what Gavin said.

There's a self correcting mechanism in play here. Bees affected coming back to the hive don't dance as much as those who aren't affected. So the rest of the colony gets directed to forage that isn't treated.

Now the report says "24h after treatment". That's ambiguous as far as I'm concerned. Does it mean up to 24 hours, at least 24 hours? The wider context which you choose not to highlight states a temporary effect. Now I've not actually had the time to read this yet, I've been busy so I'm purely responding to what's been written here rather than the full study so if I take your interpretation at face value and simply respond to what you've written/quoted I'll do the same for Gavin who states the bees were given 20 times a field realistic dose. Yet they still only exhibited a temporary effect and part of that temporary effect was not communicating that forage to the rest of the colony.

[Jon]

Nice touch - the use of red ink and bold for all the stupid people who use this forum.

Where's your scientific scrutiny?

Another study which finds unequivocally that poison is poisonous at high doses, in this case 10-20 times field realistic.
Useful to know

[Stromnessbees]

Nice touch - the use of red ink and bold for all the stupid people who use this forum.

Another study which finds unequivocally that poison is poisonous at high doses, in this case 10-20 times field realistic.
Useful to know

Jon, instead of replying to my serious concerns about Gavin's misrepresentation of this study you choose to point out my use of red ink and bold letters. This was only done to highlight the areas of contradiction, btw.

You are now sinking just as low as Gavin who has taken to pointing out all my typos - but nobody else's it seems - while still making plenty of spellling mistakes himself.

Are you still claiming to be neutral in this debate?

[Neils]

And instead of replying to my far more reasonable reply than is warranted you chose to have another go at both Jon and Gavin instead. Ms Pot I fear you complain too much about the kettles right now. So I'm done responding because it's finally, finally sunk into my thick skull that given the chance between a discussion and a poo flinging contest you'll race for the monkey suit every time and it's getting boring.

[Jon]

Are you still claiming to be neutral in this debate?

For your point of view it is not a debate - it is a campaign to get neonicotinoids banned.
You have already decided that is what you want, so the exercise from you point of view is to cherrypick, cut and paste, bold and highlight, post clips from youtube and links to websites which campaign against pesticides. In short, a low brow tabloid approach based on the idiosyncratic style of borderbeeman.

Fair enough, each to their own, but I think in a different way.
I am prepared to change my mind as evidence changes.
I have already moved from a position similar to the one you hold now, based on an impartial evaluation of the evidence, and I would be quite prepared to change position again should compelling evidence be presented that neonicotinoids are a big problem for bees.

I think they can be highly dangerous in certain situations and there is no doubt that planter dust is lethal to bees.
The overwhelming evidence around seed treatments is that they are not causing a major problem through pollen or nectar at the levels typically found and foraged by honeybees..
If insecticides from whatever class are used, it is critical to work out which are more dangerous than others to non target species - homo sapiens for example.

You clearly see this as a crusade whereas I see it as an exercise in gathering evidence. That's where we differ.