Honeybees feeding on canola die more than those which don't. Who Knew?

[borderbeeman]

http://www.scotsman.com/news/environ...land-1-2807966

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By HILARY DUNCANSON
Published on Monday 25 February 2013 00:02

A “striking” difference in honey bee survival rates between the east and west of Scotland has been recorded by scientists, prompting calls for greater action to tackle the decline of the species.

A team at the University of Dundee studied more than 600 colonies across the country in 2011-12.

Of 274 colonies examined in the east of the country, 58, or 21 per cent, failed.

By contrast, just 14 of 286 colonies failed in the west – a smaller decline of about 5 per cent.

Scientists believe the presence of intensive agriculture and large areas of oilseed rape in the east could be linked to the poorer results for the area.

But they criticised the way data on pesticide use is, or rather is not, gathered, saying the current system makes it impossible to properly determine what is causing honey bees to die.

Lead researcher Dr Christopher Connolly, of the university’s Division of Neuro-science, said:

"What we do have in the East and not the West is intensive agriculture. It could be that the lack of natural habitat is the cause. It may be that bees and other pollinators may not be getting such a balanced diet. In the west, it’s largely wild crops that they are feeding on, such as trees, heather and gorse (scotch broom). It could be that the intensive agriculture and intensive levels of pesticides are contributing to the failure of the bees."

However, even within the East, there were marked differences in death rates. Colony losses in parts of Fife were as high as 30 per cent and the Tweed Valley figure stood at 19 per cent. The City of Edinburgh recorded losses of less than 6 per cent last year.

A further study led by Dr Connolly analysed colony failures over winter across the country. Of 89 colonies that had fed on oilseed rape, 27 failed, a death rate of 30 per cent. By contrast, just 13 out of 82 colonies which had not fed on oilseed rape died – a smaller failure rate of 16 per cent.

Dr Connolly believes nicotine-based pesticides, neonicotinoids, may be contributing to the deaths of bees feeding on the crop (canola/ OSR), which is more commonly grown in the East.

He said:

“All oilseed rape is treated with neonicotinoids, you can’t buy it without it being pre-treated with neonicotinoids. Although it’s a legal requirement for farmers to record what pesticides they use on their crops, and when, that information is never gathered and stored in a central store. It’s not available to anybody. That information is missing and that is what I’m pushing for. If we can’t even learn from our mistakes, what hope have we got?”

NOTE:
you can read and download the 'hard science' evidence which Dr Connolly submitted to the current Parliamentary Inquiry on Bees and Neonicotinoids here:

http://www.publications.parliament.u...tev/668/m6.htm

Here is his concluding statement to the Inquiry:

In summary, we are playing ‘Environmental Ker-Plunk’, using pesticides to remove insect species (possibly also higher species) and we don’t know which species will be lost and how many other species will collapse with them. Eventually, the entire ecosystem will collapse unless we monitor and regulate pesticide use appropriately.

[Stromnessbees]

Beekeepers have already observed the negative impacts of these pesticides for several years.
It's good to see it confirmed in another study!

[gmcharlie]

Its been a fact without pesticides. straight canola is a know issue......

Barry any chance of slowing down this constant diatribe?
http://dspace.lib.uoguelph.ca:8080/x...pdf?sequence=1

[mgolden]

Recall previous post that indicate higher colony failure rate with hives containing mostly canola honey. Canola honey crystallizes in s short time frame. It is harder for bees to consume and not as healthy as liquid honey.

[JD's Bees]

In Alberta the total harvested acreage in 2011 for canola was 6.2 million acres and wintering losses for 2011-2012 were 13%.

[mgolden]

JD's Bees, are your bees wintering on a high percentage of canola honey and what, if any wintering problems have you experienced? Think I recall you winter in single deeps and trust you check and supplemental feed as required in ?March.

Do you harvest honey periodically over the summer to prevent canola honey from crystallizing in the comb? My thoughts are that one must have to harvest every ??3 weeks to avoid crystalized honey in the comb.

[JD's Bees]

If weather permits I start supplemental feeding in mid March. Honey harvest rotation once I start pulling is about every 10 days. Honey sometimes granulates in frames but my biggest problem is granulation in the 2 inch line from sump to settling tank if I don't extract for a few days.

[mgolden]

JD's. in the following thread, there is some discussion on merits of canola honey and wintering bees. What are your comments?

http://www.beesource.com/forums/show...granular-honey

[JD's Bees]

Well I would agree with what honeyshack had to say in the thread.
The canola honey flow here is mostly done by the end of July and because we are pulling every 10 days there isn't much time for the frames to granulate. Some years with a late spring, seeding may be delayed and that could put the flow later into August where cooler temps can lead to problems.
If I find granulated frames during extracting they are set aside to be used in the brood chambers the following spring.
With single brood chamber hives by the end of summer I sometimes have brood in all frames so I don't need to worry about stored canola honey going into winter.