The perils of Winter

By | March 23, 2013

Today most likely marks the coldest Winter in 50 years, with snow falling in London (and the rest of the UK) in the last weekend of March – one week before British Summer time starts. HA! I say likely, because we dont yet know officially how cold it will get. I suspect this weekend may break more records than first thought..

This chilly March weekend was also when we went and checked on the Walmer Gardens community hive. We’d seen some signs over Winter which didn’t bode well, but we all tried to keep our spirits up.

Still life - a dead queen surrounded by attentive, but equally dead workers

Still life – a dead queen surrounded by attentive, but equally dead workers

Unfortunately when we did open the hive, we found a dead colony with many bees littering the floor of the hive, and some left clinging to the comb. This rather morbid picture shows the dead queen (to the left and marked with a white dot) surrounded by some equally still worker bees, gathered to keep warm. Its a little deceiving as a still photo.. sadly, effectively lying in state.

So, what happened?

There was remaining stored honey and pollen in the hive, and additional candy for good measure which had been partly eaten, so we don’t think it was a shortage of food. We don’t think that disease caused the colony to die, though there was a highish varroa count near the end of Autumn, which can’t be a good thing. We know the queen was well cared for, as we found her surrounded by attentive worker bees. That the queen was still present also means the colony didnt fail because she had died.

We suspect instead the primary cause for the colony failing was due to not  enough bees to maintain warmth. We also found evidence that the bees had split into two smaller inner clusters and got isolated from each other, reducing their effectiveness at keeping warm.

As well as reducing their ability to keep warm, this also isolated bees from the food stores as they dont like to venture too far away from the warm cluster.

We think the reduced population was due to the queen reducing her egg laying too early in Autumn. This reduced lay was potentially a side effect of the Apiguard treatment – ironically a pest management substance to protect against the varroa mite *.

When we were applying the second dose of the Apiguard varroa treatment, we did notice a very low quantity of eggs and larvae. Apiguard is designed to reduce the varroa mites in the hive but can have a side effect of further reducing the queen’s egg laying rate – which is already slowing in the cooler Autumn months.

Worker bees live for around 6 weeks in Summer, and for a number of months over Winter. It really depends on how much flying they are doing as to how long they live – so rather than a life expectancy based by time, they have an odometer of flight miles.

In Autumn, it is useful to have some young bees being born just as you enter Winter, to maintain sufficient numbers through the cold months. Potentially, there were too many old bees, and not enough young bees to keep colony number up to maintain warmth and survive Winter.

People have mentioned first year beekeepers often don’t make it through the Winter – and some don’t come back for a second year because it can eb quite demoralising to lose a colony.

I’m hopeful the community based hive manage to maintain momentum, remember the honey harvested in Autumn, and can find the funds or a swarm to start a new colony.

 

* Some might ask how a tried and tested varroa treatment like Apiguard could have such an effect? When it has been used harmlessly for thousands of colonies year in, year out?
 
I believe it was due to a decision in the community group to tape the hive openings shut, to increase the strength of the Apiguard treatment. This seems to have ‘suffocated’ the bees with the thymol scent and also amplified the side effect to reduce queen egg laying, causing the queen to stop laying all together.
 
In contrast to my hive on the allotment, I didnt seal the hive when applying the Apiguard treatment. I didnt suffer amplified side effects, and effectively reduced the  varroa count within the hive.

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