The bad weather of last summer and autumn was bad news for bees

IT IS finally looking like spring, our honey bees are flying and there is some strong blooming underway. 

Bees are bringing in nectar and pollen, and the beekeepers are visiting their apiaries where their hives have been overwintering.

However, this autumn and winter was rough on bees and many beekeepers are opening hives to find their bees have died out. 

On a national level we don’t have data yet on how many hives of bees failed over the last winter, but at a recent gathering of Co Cork beekeepers in the Bessborough Centre in Cork, winter losses were the sole topic of conversation, indicating an anticipated high loss rate. 

And as our role as honeybee shepherds, or beekeepers, is to help our bees survive the winter and bring in a crop of honey in the following summer, we are all feeling disheartened and frustrated with the anticipated high losses. 

We certainly are hoping it will not be as bad as the winter of 2012 when losses of 37% were reported and many beekeepers gave up and never returned to beekeeping.

I have previously pointed out that the nation’s honeybee population is declining year on year and colony losses tend to be higher than the average in other countries.

We know that bees which suffer from parasite or disease problems do not live as long as healthy bees. We hear from beekeeping researchers that varroa mites are still the biggest threat to the health of honeybees. 

When beekeepers ask questions about colonies which have died for unknown reasons, I always ask whether they treated for varroa mites in the Autumn and again mid-winter. 

Most beekeepers tend to do this now despite the extra work and cost so the mite problem is becoming more controlled.

A number of other factors contribute to winter losses besides disease, including insufficient food, weak colonies, and local factors such as weather and floral diversity. 

What we are seeing this spring on opening hives, is small clusters of dead bees, with heads stuck deep inside the empty honeycomb. This is a typical picture of starvation but intriguingly a few inches away from these dead clusters of bees there is plenty food.

As the bee hive colony goes into winter and does not hibernate, it needs to contain a strong population of healthy bees to survive. Having enough bees in the hive in cold weather is crucial. 

The larger the winter cluster of bees, the more easily the colony can raise temperatures to a survivable range, plus a large cluster can shift position in the hive and move to additional honey stores. 

It is necessary to have least 20,000 bees per hive in late Autumn but no matter how many bees begin the winter, some will die before spring.

During winter, the cluster of bees must constantly be fueled by stored honey to produce heat, and they must move to additional honey as it is needed. 

A small cluster of bees often does not make this move over the combs to the honey. 

At the beekeeper gathering, a lot of beekeepers were reporting that, going into the winter, the hives had smaller numbers than was optimal. 

We think this was most likely due to the queen in the hive who was a poor layer and in some cases she may have failed to lay. 

Without sufficient eggs being laid the numbers of bees produced will be small. 

Maybe you can remember that the summer and autumn of 2015 was wet and very windy. We had very poor weather altogether. 

The virgin queens need to go out on mating flights to mate with multiple drones and because of either wind or rain or both, the queens were probably inadequately mated and didn’t get sufficient semen to allow them to produce high numbers of bees for the winter.

On top of this, because of the cool weather, we noticed that the ivy flower didn’t bloom as prolifically as it would normally do. 

Flower buds did appear but they didn’t mature and consequently there was a lack of the little black berries on this ivy this winter.

Ivy is one of the most important plants to provide food for bees and this was confirmed in a recent study at the University of Sussex where it was found that ivy formed the mainstay of the pollen and nectar collected by honey bees in both urban and rural areas during the autumn months.

Without a good winter store of food March can be the most difficult month for the honeybee hives that have so far survived. 

The slightly warmer weather can trigger the colony to increase its size, the queen will restart laying eggs, or increase her laying and the bees will go in search of pollen and nectar to feed the young.

The danger lies in the need to use up the last of the winter stores to give them the energy to forage, if little is available, there is a danger of starvation. 

Honeybees look for pollen, protein and fat for the baby bees, also collect nectar which is converted into honey.

In March they may feed on winter flowering cherry, pussy willow and winter honeysuckle and on top of this, beekeepers will aid them by giving them a little extra boost by supplying sugar fondant to the hive.

Despite our disappointing 2015, beekeepers are eternal optimists and this March is a time of great anticipation. 

We are all looking forward to getting ready to gather in a new crop of honey in 2016.

County Cork Beekeepers Association, http://cocorkbka.org/ 



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