Winter Preparation

Introduction

The honey bee colony builds up to its maximum foraging force in July for the summer flow when they must accumulate enough food stores to last for the next 7 or 8 months. The population of ‘summer’ bees rapidly declines from now on until there only remains a small number of ‘winter’ bees. Unlike summer bees, who only live for 5 or 6 weeks, the winter bees can live for up to 6 months. Their job is to keep the queen alive and ready to start producing brood again in a few months’ time, as well as to feed the spring larvae. Colonies can be lost in the spring when not enough winter bees have survived to keep the colony alive. The more winter bees, and the longer they live, the greater the chance of the colony surviving into the following year.

Feeding has long been by sugar syrup, fondant and pollen supplement.

Stimulating the queen to lay

Worker bees born in August and September and will die in November but those born after the beginning of October will live until next spring. It is vitally important therefore that the queen continues to lay after the summer peak to produce plenty of heathy, well-fed winter bees. This can be achieved by stimulative feeding of thin 1:1 sugar syrup, and pollen patties if there is little pollen coming in, in September to simulate a nectar flow and help the queen to keep laying. Note that thick 2:1 syrup will only be laid down as stores.

Winter stores

The average colony is estimated to need about 21kg of honey to avoid starvation. Happily for us, the bees usually collect more than they need and the surplus provides us with the delicious honey that we enjoy so much. If we take more, or if the bees haven’t collected enough, we have to replace it with some form of artificial feeding, usually in the form of sugar syrup, pollen supplement or substitute, and fondant.

We know that it is better to leave them enough of their own stores rather than feeding them sugar. Honey contains all the nutrients and trace elements that bees need for good health and long life. Sugar is junk food in terms of its nutritional value.

one full super = 12 kg

4 capped brood frames – 12 kg

Hefting the hives regularly in winter can tell us if they have enough. If the hive feels light, feeds of thick 2:1 syrup can be given as long as the daytime temperature is above about 10 deg C. Thereafter fondant is required.

If you leave the bees with a full super, t’s important to remove the queen excluder so the queen isn’t isolated when the cluster moves into the super. Whether the super is placed under or over the brood box doesn’t seem to make any difference, although bees will often prefer to move upwards, so it could be argued that above is better. In some cases, the cluster will not move up and over the top of the frames to reach the stores in nearby frames and the colony dies in what is known as isolation starvation. Communication holes made in the comb can help the cluster to move more easily from one frame to the next.

Health

A thorough health inspection after the supers have been taken off can give a warning of any adult or brood diseases which can then be treated, hopefully in time. See below on where to find more information on pests and diseases.

Varroa

Varroa infestation is one of the main causes of winter losses and must be treated now.

Although the bee population is decreasing the varroa load continues to rise exponentially and the untreated colony can soon be overwhelmed, with fatal results. Apart from weakening the adult bees and shortening their lives, Varroa can cause them to suffer from a variety of serious virus infections including Deformed Wing Virus (DWV), Chronic Bee Paralysis Virus (CBPV) and more. There are numerous approved products on the market, some containing natural ingredients such as Formic Acid, Thymol and essential oils. Others are composed of manufactured chemicals including Amitraz, Flumethrin and Tau Fluvalinate. Artificial or ‘hard’ chemicals are effective but carry the risk of the varroa developing resistance.

Whilst Formic Acid treatments are said by some to be tough on the queens or cause excessive losses, all the authorized brands are safe to use if the manufacturer’s instructions are followed to the letter, especially regarding dosage, temperature and ventilation. All are designed to kill the mites that are feeding and reproducing inside the capped brood.

Treatment must be applied after removal of the supers containing honey for human consumption. Any supers left in place during treatment should be marked to indicate that they may contain traces of the miticide used and shouldn’t be used again until the frames have been cleaned and refitted with new foundation.

A second treatment of Oxalic Acid to kill the ‘phoretic’ mites, i.e. those living and feeding on the adult bees, is given in winter when there is little or no brood. Traditionally this was carried out in late December between Christmas and New Year, but recent research has shown that in Southern England the optimum period is now early December. Treatment is by trickling the dissolved product from a syringe, using a device called Gas Vap which is a modified blow torch, or by sublimation with special equipment. Treatment with Oxalic Acid requires the operator and any bystanders to wear personal protective equipment.

Queens

Apart from Varroa and its attendant diseases, queen failure is probably the second most common cause of winter losses. Queens are at their most productive in the first 2 years of their life. After that their egg laying capacity declines and they are likely to be superseded. Unfortunately, the chances of a replacement queen being mated are diminishing rapidly and both the old and the new queen will fail to survive.

Now is a good time to introduce new, mated queens which are ready to produce the vital winter bees needed to see the colony through winter and into spring. If the old queen has good genetic traits, and you can’t bear to part with her, she can be retired into a nuc and used for emergencies such as making up winter losses, or for raising new queens next year.

Young queens in their first 2 years are less inclined to swarm the following year. Those that do make swarm preparations will pass on the trait to their offspring and their drones will spread the swarmy behaviour to other colonies in the area. The colony should be requeened as soon as practicable.

Similarly, if the colony has been excessively defensive or flighty during the season, requeening now will improve the temperament of the colony and make your beekeeping a pleasure again, as well as not spreading the undesirable genes to other beekeepers stock by its drones.

Like humans, not all queens are born equal and poorly mated or badly developed queens will fail early in their lives or be superseded.

Pests and predators

Mouse guards and woodpeckers. Mice are sometimes tempted into hives at the start of winter by the prospect of a warm home in which to hibernate. Mouse guards fitted in October will deny them access. In a hard winter when there is little food available, green woodpeckers will drill holes in the side of hives and raid the contents causing considerable damage and often leaving the colony to die of cold or starvation. A cage of chicken wire around the hives will prevent the birds from attacking them.

Insulation

A layer of insulation in the roof of wooden hives can help to keep the cluster warm and reduce the quantity of stores they consume in order to produce heat. The winter bees are more rested and likely to live longer. Insulated hives enjoy better winter survival rates and faster spring build up. Poly hives and nucs have an advantage in this respect.

Summary

• A colony that is fit, strong and well fed, with a productive young queen, will have a better chance of getting through winter and spring.
• Bees born in August and September will die in October and November. Bees born in October will live until the following spring.
• Feeding of thin 1:1 sugar syrup in September will stimulate the queen to lay in October and produce the vitally important winter bees.
• Feeding of thick sugar syrup be laid down as stores.
• Feeding with fondant will see the colony through times when it is too cold for the bees to consume syrup.
• Varroa treatments in August and December are required to prevent winter and spring losses.
• Colonies led by young queens are much more likely to survive than those with older queens. They are also less susceptible to swarming the following spring.
• Protection against mice and woodpeckers is fitted in October.
• Insulation can make stores last longer, extend the life of the winter bees, and help the colony to grow faster in spring.

Further reading: The Beelistener – Ann Chilcott’s beekeeping site, with articles and research summaries on bee health, varroa and winter survival.

References:

BBKA Healthy Hive Guide

BBKA Special Edition: Feeding Honey Bees

Baxter A. https://www.alanbaxtersblogs.co.uk

National Bee Unit Managing Varroa https://shorturl.at/ysjpR

Stainton, K. (2022) Varroa Management: A Practical Guide on How to Manage Varroa Mites in Honey Bee Colonies, Northern Bee Books.