Our honeybees don't hibernate, but they certainly slow right down and become torpid as the daylight hours shorten and temperatures drop. The colony will stay in the hive for the duration of the winter only coming out on the sunniest days to perform cleansing flights or to gather pollen from the winter flowers such as ivy (Hedera spp.) weather permitting. The brood in the hive will have diminished to a small amount as the bees have to gather closer together to provide the necessary heat. The queen will continue to lay eggs but to a much lesser extent. Its thought that only in the furthest north extremities of our honeybees range does the queen stop laying all together and then only temporarily. Remembering that during the season bees only last 5 or 6 weeks it makes sense that the queen will continue to produce brood as long as there is pollen and honey to feed them with, and as long as the temperature in the hive permits. As the winter deepens and temperatures fall and stay low the colony will cluster together around the queen and brood to keep warm, gradually using up the stores of pollen and honey in the hive. Adult bees will be quite old, perhaps a couple of months old, and many on the extremities of the cluster will gradually die off gradually through the winter.
The cluster will move up in the hive when it is very cold and will remain there surviving on stores in the immediate vicinity. It is an unfortunate fact that many colonies are lost in winter because of 'isolation starvation' when they are clustered in the top of the hive having used up all the stores there, yet unable to move to the plentiful stores in the next but one frame. The reason for this is that the honeybee simply seizes up in the cold and can't move, and perish quickly. It is imperative that the colony has stores available and that they can access them.
Preparing your colonies for winter is essential. A healthy colony will require 15 - 20 kg (30 - 40 lbs) of stores to see them safely through to April. It starts when you are making decisions about harvesting the Autumn crop, do you leave it for the colony to over-winter on? Is it enough? Do you need to give them supplementary feed? If you have harvested the Autumn crop then the answer is that you must feed them up with heavy syrup while the temperature still permits the bees to ripen it in the hive. If you feed syrup into the hive later when the temperature is too low (lower than 8℃) the bees can not reduce the water content and it will simply ferment and go off in the comb, and cause dysentery. The bees will take the syrup down and fill up available space around the nest, but if there are no honey supers left on, it will not be enough. They will need more food as the winter progresses and the stores in the brood box are used up. An eke on top allows enough room to place bags of fondant or blocks of candy on top of the brood box frames. Alternately you can put an empty super on with bags of sugar laid directly on top of the brood frames. Prepare the sugar bags by piercing the paper bag with a fork and submerging in water for a few seconds. The water dampens the sugar which solidifies somewhat, avoiding sugar grains cascading down through the hive when the bees chew through the paper. As an emergency measure you can use a frame of honey laid across the top of the brood frames but they will use what they can access quickly. Avoid leaving open space above the brood frames as heat from the colony will be lost, use quilts or bubble wrap to fill the gaps and provide some insulation where necessary.
Eventually in the cold weather the colony will cluster together in the top of the hive, in the honey supers if you left them on, or in the food in the eke. It is essential that any queen excluders have been removed to allow the queen to move freely with the colony, keep them above the quilt or cover board until spring. Winter weather is likely to include high winds, driving rain, sub zero temperatures and snow. Check that hive boxes fit well together without gaps where killer drafts can get in, use gaffer tape round the joints if necessary. It's worth remembering that out of season the bees can't produce the propolis necessary for plugging and sealing gaps that were left after a late autumn / early winter inspections. In a well sealed hive the colony will regulate its own climate and remain cosy. Mouse guards should be in place and secure. Make sure roofs are secure, and weighed down with stones or bricks. Inspection boards in varroa floors have a habit of blowing out in the wind, secure them in place or change for a solid floor. Snow happily drifts up the front of a bee hive and seals up the entrance where air vents and prevents the bees getting out on sunny days. If you can't get in to clear snow drifts, a large board can be placed against the front of the hive to stop snow sealing the entrance, but beware of creating a sail effect which may result in the hive being blown over.
Through the winter the bees will remain tight in the hive only venturing out on the brightest calmest days when the sun's rays heat the hive up enough to allow the colony to move freely and fly out for a brief period, primarily to void their bowels. They won't stay out long and will swiftly go back in as soon as the sunshine disappears. In the very cold and wet winter periods they will cluster tightly together generating just enough heat to keep the queen and any brood alive. During this time there may be a complete lack of bee activity at the hive entrance for weeks and you may be tempted to make a disturbance, like tapping on the hive walls, just to see bees appear or hear the colony inside. Don't! as this will unsettle them breaking up the cluster putting them on alert which will cause them to use up energy and precious stores, and it can 48 hours or more before they fully settle down to a cluster again. The cost of that may be fatal to the colony in the long run as numbers and stores are prematurely depleted. Bearing that in mind, periodic inspections involving a quick look under the crown board to check where the bees are and if they are getting the food are necessary. Do this on a good day when there is least chance of chilling the colony, and have suitable replenishments at hand. If you can see bees on top of the frames then they are hungry and need feeding quickly. Keep an eye open for signs of vermin trying to get in, mouse guards are good but rats will gnaw right through the wood of your hive. Keeping the grass around your hives low and keeping your hives raised off the ground helps deter unwelcome visitors.
Be confident that a healthy colony, in a weather tight hive, correctly prepared with sufficient stores, will over-winter successfully with very little intervention necessary, and will be snug in the hive even if you don't see them for months!
Once you have prepared your apiary for winter and your beekeeping activities have reduced down to periodic inspections, its a good time to reflect on the years activities and to plan next years. Time to go over your notes and analyse what went well, what didn't go well, which colonies performed well and which didn't, and planning what you will do differently. Effect any repairs that are outstanding, and replace old and damaged equipment. Winter lectures are often provided by associations during the winter months and are a good way of catching up with fellow beekeepers.