[Pollinator] A new paper shows mixed effects of neonics on honeybee hives

[Clement Kent]

Hi Hollis - a couple of my colleagues pointed out the different conclusions
between the just published Dively et al and last year's Sandrock et al
studies. Both found poorer one-year survival of queens, but they differ in
the short term effects shown. My colleagues noted that Sandrock et al made
sure the pollen patties containing neonics were fully consumed, while
Dively et al did not. Another difference is that Dively et al used
imidacloprid, while Sandrock et al used thiamethoxam and clothianidin.

Although the differences between the studies are interesting, the fact that
two studies both using field-realistic exposure levels of two different
neonics found poor one-year queen survival after exposure is probably the
biggest message I see here.

Clement

On Fri, Mar 20, 2015 at 11:37 AM, Hollis Woodard <euglossine at gmail.com>
wrote:

> I totally agree, Clement. And we're already seeing the
> misuse/misrepresentation of this article in the media, like this article in
> the Guardian, which claims that "Research by the University of Maryland
> this week found that a neonicotinoid developed by Bayer, imidacloprid,
> isn’t the main cause of higher death rates in honeybee colonies in the US
> over the past decade."
>
> Um.. no it didn't.
>
>
> http://www.theguardian.com/sustainable-business/2015/mar/19/pr-battle-neonicotinoids-decling-bee-colonies-food-security?CMP=share_btn_tw
>
> --
> S. Hollis Woodard, Ph.D.
> Section of Integrative Biology
> The University of Texas at Austin
>
>
> On Thu, Mar 19, 2015 at 11:32 AM, Clement Kent <clementfkent at gmail.com>
> wrote:
>
>> A new paper (Dively et al. PLoS One 2015, "Assessment of Chronic
>> Sublethal Effects of Imidacloprid on Honey Bee Colony Health") makes
>> interesting reading. Honey bee colonies were exposed to imidacloprid in
>> pollen patties within the hives, and many variables relating to hive health
>> were tracked.
>>
>> It will be important for a clear understanding of the issues around
>> neonics to read this study carefully.
>>
>> Some important points to consider:
>>
>>    1. exposure to imidacloprid was via pollen patties.
>>    - question: how much in-hive pollen do foragers eat?
>>       2. strong effects of imidacloprid on colony survival over winter
>>    were shown (their Figure 9,), but
>>    3. effects on other endpoints were not significant.
>>
>> As a result of point 3 above, supporters of continued neonic use will
>> quote this article as showing no ill effects of neonics on bees.
>>
>> Those wishing to support a more scientifically complete viewpoint will
>> need to draw attention to points 1 and especially 2.
>>
>> The study is freely available at
>> http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0118748
>>
>>
>> Clement Kent
>>
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>>
>
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