17 April 2013

Overview of 2012 - 2013

It's hard to know where to start when trying to explain what went wrong during a beekeeping year, because the roots for a poor season start to develop during the previous year. The winter of 2011-2012 was harsh and cold, but bees can cope with the cold as long as they have enough food and their home protects them from the weather.

2012
The year started cold, then it warmed up quite quickly. The bees enjoyed this early hot spell and built up earlier than usual, so much so that some beekeepers were caught out and lost early swarms.

Then it rained, and rained, and rained.

In our part of the country it rained almost constantly from April through to December, this affected almost every possible aspect of beekeeping.

Swarms
Swarming is the bees means of reproduction, and can be triggered by lack of space. The 'prime' swarm comprises the existing queen and almost all the flying bees, they leave once swarm cells are capped which gives time for existing 'house bees' to develop into flyers and be ready to accompany a virgin queen on her mating flights.

Beekeepers do their best to pre-empt swarming, and will split a colony by separating the queen and flying bees from brood and house bees. The wet weather it made this difficult, swarms were lost to an uncertain future as feral colonies. Some of these will have starved during the 2012-2013 winter.

Forage
Bees need both nectar and pollen. Nectar provides them with carbohydrates, pollen is protein.

When it's cold and damp flowers will not release their pollen, so even if the bees are flying there is nothing to collect. Constant rain can make pollen rot on the flowers, and constant heavy rain can wash the pollen from the flowers leaving the anthers bare.Rain washes nectar out of upward facing flowers - so there's no nectar available during a brief spell between periods of heavy rain.

This lack of forage meant that beekeepers were feeding their bees throughout what should have been the main honey flow, and because even the Ivy failed to produce much needed pollen and nectar, they had to continue feeding into the autumn to ensure the colonies had enough stores for a normal winter.

Queens
A new queen has to make several flights during just a couple of weeks otherwise she becomes unviable. Her first flights are to orientate, and learn where her home is. Later flights are to drone congregation areas, where she is chased by a 'comet tail' of drones hoping to catch and mate with her. She needs to be inseminated by between 15 and 20 drones to be a long-lasting, useful, queen.

The incessant rain meant that new queens couldn't fly, so mating would have been at best erratic. The knock-on from this will be either failed queens - with colonies passing into spring with no new eggs, or drone laying queens - those that lay only unfertilised eggs. Both can be a disaster for a small apiary owner with only a couple of hives, a death sentence for an unmanaged feral colony.

Honey
Some colonies failed to store enough honey to survive the winter, beekeepers provided what should have been enough supplementary food to get them through a normal winter, but the winter 2012-2013 proved to be far from normal and supplementary feeding of both sugar and pollen substitute has continued through into April.

Varroa
This insidious mite can cause havoc to a colony of bees. Not only does it weaken them but it is also a vector for disease.

Treatment involves, at the barest minimum, opening the hive and dusting with icing sugar - intended to persuade the bees to groom each other and so knock off mites. Other treatments require some warmth to be effective, so need to be done late August or early September otherwise the thymol will not evaporate and circulate within the hive. Those beekeepers who had optimistically taken their bees to heather, or whose bees were within reach of heather, found it was too cold to use thymol once the honey flow had ended.

Mid-winter varroa treatment needs a broodless spell to be effective. Around Christmas temperatures warmed up enough to persuade the queens back into laying - so Oxalic Acid will have been less effective.

In USA beekeepers reckon that a daily varroa drop should be no greater than the number of the month (i.e. July =7) before treatment is needed. The Beebase varroa calulator is here.

2012-2013
The winter seemed to be a fairly reasonable, although wet, one, which offered a glimmer of hope after the previous poor year, but then March turned cold and some parts of the country were blanketed in snow. It was the coldest March for tens of years, and DEFRA sent a "Starvation Risk" warning to all registered beekeepers.

The cold, on its' own, wouldn't have been too bad, but coupled with winter floods, low stores, poorly mated queens it was a disaster for the bees. The weather stopped some beekeepers being able to reach their apiaries, and indeed some had to take to boats to rescue hives from floodwater. Rescuing was all they could do, and then hope for the best.

Inspections can only be done when it's warm enough for bees to fly, earliest inspections have proved that the worst fears have been realised, with colonies dead from starvation or showing signs of varroa vectored disease. I still haven't been able to do more than check for stores, it's still far too cold to lift frames. We're already a brood cycle behind what should be 'normal' for this time of year.

Spring is desperately late arriving. We're now into the middle of April and still no sign of leaves on willows, no sign of hawthorn, sloe or apple blossom. DEFRA issued a warning advising "Pollen Substitute Feeding".

Local 'old beekeepers' said that 2011 was the worst year ever, 2012 was worse than that. Let's hope that 2013 doesn't break this 'worst ever' record.

At the moment the best we can hope for is that surviving colonies will have enough time to build up, and time to store enough, to make it through next winter.

~'.'~

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