Exposure to neonicotinoids impairs honeybee winterization before colony collapse
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For what it's worth, EconTalk had a really fascinating interview with a honeybee economist (<-- thing that exists!).
Turns out:
* Practically 100% of US honeybees are domesticated; wild honeybees were wiped out in the late 80s by Varroa mites.
* Honeybees aren't native to the US; I'm not sure if I heard this right, but it may be that none of the social bees are.
* Colony collapse is largely a phenomenon observed during overwintering. Some 15% of domesticated colonies fail over the winter. CCD seems to have upped this figure to 30%.
* If CCD is causing problems for professional beekeepers, those problems don't seem to be reflected in the economy. The price of queen bees (raised by specialized apiarists to help other beekeepers split colonies) hasn't changed. The price of pollination services --- mostly for the California almond crop, which is fed by beekeepers from around the country --- hasn't changed significantly either, with the possible exception of a small spike in pollination fees at the peak of almond pollination season.
It's hard to reconcile what the economist reported with the alarmism surrounding colony collapse.
It's also difficult to compare the impact of "neonicotinoids" with that of the Varroa mite.
Both wild and domesticated Honey bees were present in the Americas when European colonists arrived. However, the common honey bee was not among them, and the other (I hesitate to say 'native') species are indeed no longer extant.
If CCD is causing problems for professional beekeepers, those problems don't seem to be reflected in the economy. The price of queen bees hasn't changed.
Queen pricing might not be as strongly correlated to CCD as you might expect. Raising queens is indeed done commercially by specialized beekeepers, but if you're already a beekeeper, it is not hard to do or learn. You can raise dozens at the same time, in a single hive, and this does not stop that hive from producing honey later in the season. It's therefore quite possible that the increased demand in queens after overwintering has simply been met by an increase in the supply.
I think that this is the earlier point--
(ie, with no huge price ∆)
Sort of - native American bees are generally less social than true honeybees and generally produce some but less honey than true honeybees.
On the other hand, hives treated with neonicotinoids were deserted during the winter.
It's good to know that the CCD hasn't had any impact on the economy.
To wit: if pesticides are wiping out the honeybees, and honeybees are in very high demand to pollinate crops (they are: honeybees are trucked from Virginia to California to work the pollination circuit), the economy should clearly indicate that ecological problem happening.
The point about the Varroa mites is tangential. Or rather, two tangents:
1. Compared to even double-digit overwintering losses, pesticides are nothing close to the problem that mites were; mites eradicated the wild honeybee population! According to the EconTalk interview (this blew my mind and I wouldn't be surprised if it's a drastic oversimplification), if you see a bee in your backyard, and it's actually a honeybee, it's domesticated; its home is some apiarist's colony nearby.
2. The honeybees we're concerned about are themselves not native to the US. Honeybees are a species people introduced to North America.
That's how I interpreted it.
"Bees and the crops they pollinate are at risk from climate change, IPCC report to warn" (7:00AM GMT 29 Mar 2014)
http://www.telegraph.co.uk/earth/earthnews/10730667/Bees-and...
There is alot of multi-colinearity in these data-sets, and the attribution issues are non-trivial.
You can fudge a lot of news and spin things various ways, but if you're paying the same amount now as you were 10 years ago for pollination? I'm not sure where the problem is.
1) There is no mention of whether the people caring for the bees were blinded as to control versus treatment. This is simple, and should have been done if it was not.
2) There were only 6 hives in each treatment group (control, imadacloprid, and clothianidin). There are always constraints, but more hives would be a much stronger study.
3) Lu's previous study found 100% mortality with 1/7th the dose of imadacloprid. Why did they increase the dosage for this experiment?
4) There are 3 apiary locations, but they don't report the breakdown per apiary. Did all the apiaries experience approximately equal losses in the neonicotinoid hives?
5) Is there a "file drawer" effect here? If there had been one fewer treatment hive collapse and one more control collapse, would this study have been published?
6) Were any other studies performed? Or started and abandoned? I'd presume not, but it would be great to have a clear statement from the authors.
7) Is it reasonable to assume that the dosage is spread evenly across all bees? If the clothianidin LD50 is 3.4 ng/bee, and they are administering .74 ng/bee/day, it seems likely that some bees will die from acute poisoning.
8) They don't breakdown the numbers per hive, and instead give averages that include abandoned hives. Were the surviving non-abandoned neonicotinoid hives any weaker than the control hives?
My hope would be that the authors would provide the full data if requested, but I'm constantly surprised that journals don't require this. Without additional information, this seems like an interesting exploratory study that neither confirms or denies any specific hypothesis.
I'd guess that there are enough beekeepers interested in future studies that a larger scale study would be possible. Many bees are fed over the winter with sugar, to compensate for the honey that is taken. Do you suppose that there are beekeepers that would agree to a blind dosing of their bees if the lab were to provide the (possibly poisoned) sugar?
These bees are fundamental to the production of most vegetable matter that we eat. The financial implications of the loss of these insects is huge compared to the 'loss' of money the insecticide companies would bear if these chemicals were banned from sale.
"A survey of honey bee colonies revealed no consistent pattern in pesticide levels between healthy and CCD-affected colonies when pollen, bees, and beeswax were tested for the presence of 170 pesticides. The most commonly found pesticide in that study was coumaphos, which is used to treat honey bees for Varroa mites.
The pesticide class neonicotinoids (clothianidin, thiamethoxam, and imidacloprid) has been accused of being the cause of CCD. The neonicotinoids were developed in the mid-1990s in large part because they showed reduced toxicity to honey bees, compared with previously used organophosphate and carbamate insecticides."
I see lots of articles on bee decline, often blaming pesticides, but they don't seem to have affected wild bees (from my informal survey anyway). These wild bees are very similar to honey bees... I doubt an untrained person could tell the difference. I wonder why the decline in one and not the other? It seems pesticides would affect them both. My guess it has to with genetics and/or cultural techniques. I see mites mentioned sometimes as suspect.
I think the difference probably comes from the practice of transporting domestic bees to large orchards and vegetable fields for pollination services, where their diet is almost exclusively limited to agricultural products (which are sprayed).
Furthermore, the results are jarring. Bees deserted the twelve hives treated with neonicotinoids, to the point that half of the hives died. The survivinghives were seldom populated and either without queen or without brood.
There was no desertion in the control group. One hive of the control group died of some disease, but the hive was full.