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Posted 23 April 07

Is ‘Colony Collapse Disorder’ a Condition Resulting from ‘Suspect’ Pollen Quality and Compounded by Honey Glut in the Brood Nest Restricting the Queen’s Laying?

Eric McArthur

I have been keeping bees in the Glasgow area for around 40 years and I am now almost convinced that the present ‘Colony Collapse Disorder’ being experience in most countries where bees are kept is due in some way to the quality of pollen and honey, which the bees have available to them in the hive food stores gathered in the previous season. Another detrimental aspect of CCD seems to be that the combs in the hives in which colonies fall victim to the condition are solid slabs of honey. Such volumes of honey especially if the ‘glut’ of honey results in a dramatic restriction of space available for the queen to lay eggs in the late summer will cause the colony to enter the winter with a preponderance of old bees, which will die off very quickly as the winter progresses. As the colony population dwindles less food is consumed and the honey glut will persist into the late winter period when traditionally the queen will resume egg laying. If her laying space is still restricted few new young bees will be reared to replace the steady loss of the older bees.

On the 13th April 2007 I did an internal spring check of my colonies at an apiary in Strathblane, near Glasgow. It had been a fortnight since the previous visit, which was merely a non invasive check on the number of frames the bees were covering in the hive. Within that two week time window 11 of my colonies had dwindled to covering between one and two combs, instead of expanding as is the normal case as spring moves into summer. The shock of seeing previously prosperous looking colonies reduced to just one or two frames of bees was quite daunting.  Especially since all of these colonies contained brood combs with virtually slabs of honey in them and very little brood.

This site in the past was an over-wintering apiary for bees coming back from the heather moors in early September; however the heather in my area in the West of Scotland has all been killed off by the predations of a parasite, aptly named ‘The Heather Beetle’. These hives remain in situ all year round now.

Over the time from the heather demise, some three years ago, I have noticed a steady increase in colony losses at this site, despite the bees having adequate stores of pollen and honey at the start of the winter, however the surviving colonies were able to build up sufficiently well for the late summer flows from willow herb and Himalayan balsam.   I have felt for some time that although the balsam and willow herb at this site secrete nectar well, the pollen of these plants is somehow inferior for brood rearing, much the same as dandelion pollen, which has been proved scientifically to lack a particular protein and is useless for brood rearing on its own! 

I feel that in the past the bees built up each spring on the previous autumn's stored heather pollen.  The build up on balsam and willow herb pollen seems to be slower - almost like a borderline malnutrition condition. The weather this late spring/early summer has been stunningly fine since the 22nd March and the bees have been flying steadily at all the apiaries - but the Strathblane site is a poor ‘early pollen’ location - plenty of snowdrop, on which the bees did well;  virtually no crocus, catkins, blackthorn or Norway maple - in a word, only marginal pollen available in the immediate apiary vicinity.

Normally the bees do not have such long settled flying conditions as this year and I feel that that is also a contributing factor to the present situation. In a 'normal' year the bees are much less active, than they have been this year.  The bees have had a longer time for flying this spring and thus more time to lose the older less able bees.

The result seems to have produced a scenario similar to 'Colony Collapse Disorder' in my case.  I am certain that although my experience above might not be the whole story - it could be a factor in many of the cases which have occurred to date. 

There is another important factor in the over-wintering honey bee colony. Most of the bees in a honey bee colony in the early spring are young bees reared in the hive from around the middle of January. If the pollen in the colony is of poor quality the resulting increase in the young bee population could be drastically affected. Consider however; many of the countries and regions experiencing CCD have considerable acreages of conventional OSR and Canola and sunflowers. Vast amount of systemic pesticides are used on these crops. In my opinion the pollen and honey stored in hives in the vicinity of these crops could have been contaminated by even trace levels of these systemic pesticides, which have already been shown to have low neuro toxic effects which impair bee orientation ability

An analysis of pollen stored in a CCD affected colony might be very revealing. The fact that no robbing out of the stores in a CCD affected hive is a significant pointer that any contamination of pollen and honey is sensed by as yet unaffected bees.

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This piece appeared in the “Scottish Beekeeper” magazine in January 2002

IMIDACLOPR1D

R.G. LEGG, Heards Farm, Brentwood

This could be an interesting/worrying development! Winter oilseed rape now has clearance for Imidacloprid seed dressing, sold as Chinook.

Two thirds of the seed I have sown this year has been treated with Chinook and one third with methiocarb. These seed treatments have replaced Lindane, the application of which has been banned in the UK for several years but Lindane-treated seed can be imported and is widely used.

The use of insecticide-treated seed is essential to the establishment of OSR due to the devastation caused by cabbage stem flea beetles. The alternative treatment would be two or three well timed applications of a broad spectrum insecticide - not easy, not always successful, and these would also kill beneficial and predatory insects. With seed costing from £3,500 to over £10,000 per tonne the £65/tonne extra for Chinook is worth it - as you only get one chance to establish a decent crop. With about 200 days between sowing and f1owering compared to 50 for sunflowers hopefully our bees will be safe. Any over wintering honey bee losses would not show until Spring 2003

More worrying is the loss of area payments in the UK which will make OSR unviable to grow in the present political environment and which will suck in US produced and heavily subsidised Soya (GM?) 1' and remove our main crop.

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