What do bees do in winter?

Have you ever wondered how bees survive the winter? While wild bees have a number of different hibernation strategies, honeybees spend the winter together in their colony.

Winter is a critical period for bees. They do not have access to food in the form of pollen or nectar from flowers, and they have to deal with the cold temperatures. Various bee species have adapted to these adverse conditions in their own unique ways. In this article you will learn where and how bees spend the winter. We also give tips on how to support bees and what to do if you find a bee in the dead of winter.

Do bees die in winter? Yes and no. Many bees do not survive the winter. From around September, honeybees (Apis mellifera) lay eggs that hatch into winter bees. These survive the winter. Summer honeybees, however, die in autumn. In winter, a honeybee colony is only about half as large as it is in summer.
Among the many species of wild bees, there are different strategies: Most adult wild bees also die in autumn, with only a few surviving the winter in hibernation. The eggs and larvae of most wild bee species survive the cold season.

Where do bees go in winter?

Not all bees are the same. There are many different species of wild bees, each with its own strategy for ensuring the next generation the following year.

Where do honeybees go in winter?

Honeybees overwinter together as a colony in their hive, where they form the so-called winter cluster.

Where do wild bees go in winter?

Most wild bee species are annuals, meaning the adults die in autumn. Therefore, the majority of adult wild bees are no longer alive in winter. During this time, the next generation is hibernating as eggs, larvae or pupae in plant stems, wooden cavities, sand holes or abandoned snail shells. In these early stages, they are usually much more robust and less sensitive to the cold.

However, there are some exceptions, including:

Bumblebees (Bombus): Bumblebees typically live in colonies of up to 200 workers. These are rather small compared to honeybees colonies, which number in the thousands. In autumn, all of the drone and worker bees die, while the new young bumblebee queen survives. The young queen finds a place to hibernate alone underground (for example, an abandoned mice hole) and establishes a new colony the following spring.

Large carpenter bees (Xylocopa): Large carpenter bees overwinter alone or in small groups in their self-made nests, tree hollows or crevices.

Small carpenter bees (Ceratina): Male and female small carpenter bees overwinter together. Unlike large carpenter bees, they usually find their winter quarters in hollow plant stems like blackberries, elderberries, mullein or hedge roses.

What happens to bees in the winter?

The winter goal of all bees is for them and/or their offspring to survive. Different species have developed different strategies to accomplish this.

What do honeybees do in winter?

Honeybees overwinter with their colony. They cluster together in the hive and usually stay in the hive during the whole of winter. They survive the cold season by feeding on the food reserves they built over the summer. In apiaries, the beekeeper usually provides food for the hive in the form of sugar water.

Winter cluster: Honeybees overwinter in what is called a winter cluster. As the queen is the most important bee in the colony, she enjoys the centre of the cluster. Around her, the other bees use movement to create friction, which keeps the temperature between 15 °C and 25 °C. As they move, they swap places and take turns moving towards the outside and inside of the winter cluster.

What do wild bees do in winter?

In a nutshell, not much. Since the adults of most wild bee species die in autumn, only eggs, larvae or pupae have to survive the winter. The few adult bees that do not die in autumn hibernate during the winter. Until the temperatures rise in spring, the bees are immobile in their hibernation.
Bumblebees hibernate underground to protect themselves from freezing temperatures. Bee species that overwinter above ground have developed methods for lowering the freezing point of their body fluids, allowing them to survive temperatures below 0 °C.

Do bees hibernate in the winter?

Hibernation is a state in which some warm-blooded animals, like mammals and some birds, lower their body temperature. In this state, their heartbeats and breathing rates slow down, so that they use less energy. This usually allows them to survive the winter on their fat reserves.

Honeybees cannot hibernate because they are cold-blooded. They do, however, reduce their metabolism slightly and rarely leave the hive in winter. In this sense, they go into a kind of hibernation. Honeybees, on the other hand, stay active all winter to keep the hive warm. So, it is perfectly normal to see honeybees out and about on the occasional warm day in January. They use warm winter days for their cleansing flights and to collect pollen from winter flowers.

Depending on the species, wild bees survive the winter as larvae or adults in so-called hibernation. Bee hibernation is comparable to that of warm-blooded animals. However, there are some differences. In mammals, hibernation is induced by hormones. If they are disturbed during hibernation, they can become active again, for example to go in search of food. To do this, they temporarily raise their body temperature. In cold-blooded animals, hibernation depends solely on the outside temperature – they cannot warm themselves. Therefore, hibernating wild bees cannot move, because even in mild winters the lowest temperature at which they can move is rarely reached. In return, however, they do not need as much energy to be able to survive the winter.

Should bees be fed in winter or supported in other ways?

What bees eat in winter also varies from species to species.

Since honeybees are active during the cold season, they need sufficient food reserves. People who keep a honeybee colony and harvest the honey in summer, have to feed the bees in winter. This is usually done with sugar water.

Wild bees do not eat during the winter. Nevertheless, there are things you can do to help them during the cold season.

• Wild bees often choose flower meadows, berry and other shrubs as well as hollow stems of deciduous perennials and annual plants for their winter quarters. Therefore, wait until spring to prune these plants.
• Ensure that food is available in the garden as early as possible and that it lasts well into the autumn. Early flowering plants that provide pollen include crocuses (Crocus), snowdrops (Galanthus), hazelnuts (Corylus avellana) and alders (Alnus). Autumn asters (Symphyotrichum and Aster) and stonecrop (Sedum), among others, provide a sufficient food supply in autumn.
• Leave some leaf piles and dead wood lying around. This makes it easier for bees, as well as other garden animals, to find a place to overwinter.
• Insect hotels also provide a place for laying eggs and overwintering. Check out our article on nesting habitat for wild bees for a summary of what to consider when buying or building your own.

There is not much more you can do for the little helpers in winter, which is why it is all the more important to support the bees during the rest of the year. If the bee pasture is left untouched over the winter, it provides plenty of shelter not only for wild bees, but also for other insects. Many butterfly caterpillars overwinter in hollow stems or deadwood as well.

What to do if you find bees in winter?

It is not uncommon to see bees flying on warmer winter days. Since honeybees do not technically hibernate, they can quickly become active again. They use these warmer days for cleansing flights and to go in search of water and food.

Sometimes bees have enough energy for take-off, but then they use it all up or a change in weather makes it difficult for them to fly home. So, if in winter you find a bee in your house or flat that seems weak, place it on a plate with honey or sugar water in a spot that is at least 15 °C. This way it can warm up and recharge its batteries for the flight back to its colony where it can survive the rest of winter.

That said, some bees leave the hive because they are sick and will die. If such a bee is found in winter, sugar water and warmth will not help it.

Although less common, you may also happen across hibernating wild bees, for example in wall crevices of a house. It is best not to disturb these bees.

Winter is hard for many. Therefore, we have put together an article full of useful recommendations on how you can help garden animals in winter.