For the last few years as I can recall, the Winter has been mild with little or no snow. This year, it has been freezing cold, and very wet, and with a short but heavy snowfall, so my attention is drawn to the amount of feed stores left in the hives. Throughout Winter, honeybees don't hibernate. What they do is cluster in a rugby ball shape, keeping the Queen (in the centre of the cluster) quite warm at a steady 35°C. They generate heat by vibrating their wings. Honeybees can do this by effectively dislocating the flight muscles, so the wings can vibrate without taking flight. The kinetic energy to do this is enough to generate heat. If you put your hand on top of the hive when it is open, you can feel this heat quite easily as it rises up through the frames.
Of course, not hibernating means the bees constantly need to eat. A typical hive, like you see in the apiary photo will need at least 20Kg of honey stores to make it through Winter without starvation. Taking too much honey from the bees in late Summer is a rookie mistake, and new beekeepers often find in Springtime that the colony has starved. As soon as I have taken some honey from the bees, I always put a sugar feed on the hive to help them replace the lost stores. Throughout the Winter, I also give them a slab of baker's fondant (icing) which they can take or leave.
The square frame you see on top is called an 'eke'. We use these to create height to allow us to put food trays on top. Otherwise the roof would not sit properly. The board with the oval cutout is called a crown board, and is effectively an insulation board, with a hole to allow me to feed the bees. Some of my crown boards have perspex boards, so I can see into the top without lifting the board off. But these do not have holes in so I don't use them when I need to feed. It is good practise not to disturb the bees whatsoever, unless you really need to.
I cut the fondant and put it in an upturned takeaway tray. This stops it drying out. If the bees are hungry, they will take it. If not, then no harm. It's a safe way to be able to leave them to their own devices over winter and not disturb them too much. I will probably only open up the top to check on the fondant level every 2-3 weeks.
Here's a close up of the hole in the crown board. You can see how the heat from the hive has been warm enough to melt the fondant from the previous tray. The picture shows that my bees look healthy and clean, so it is looking good for Springtime. Normally bees only live for around 6 weeks. They literally work themselves to death in the Summer. However, because they are not working hard in the Winter, they live longer. All the bees in the hive in Winter are female workers, and the Queen. All the male bees (drones) were ejected from the hive in late Autumn. The male bees do not do anything other than try to mate with a Virgin Queen. When not out on a mating flight, they just hang around the hive and do no work at all, just eat. So, to save food, the girls kick them out in Autumn.
Because the worker bees are quite old now, it is really important to get the Queen laying in March and to get new bees up and running to work the hive. The next few weeks are critical. I saw a large drift of snowdrops emerging near my hives, so as soon as it is warm enough (14°C) the bees will be out collecting the snowdrop pollen.