Most of us are aware that bees are much more active in the spring and summer months when they can be seen hovering about plants collecting nectar and pollen from various flowers. But what happens to them when the weather gets cooler? What do bees do in the winter? Where do they go?
Do Bees Hibernate or Die in the Winter?
Since it is very uncommon to see bees in the winter, the question of whether they hibernate is one many people tend to ask. Then there are those that think the cold weather will kill bees during the winter months.
Fortunately for the bees, a healthy colony will not usually be killed by cold weather. Bees are adept at working together to keep the temperature of their hive warm enough for them to survive. However, the beekeeper will need to do their part as well. Wind and moisture are big problems for honeybees, so the hive needs to be made secure during the winter if the colony is to survive.
While some bees will inevitably die during the winter months due to reaching the end of their natural lifespan, there are some – known as winter bees – that have a longer lifespan of around four to six months. These plumper bees help keep the heat within the hive.
Despite not leaving the hive during the winter, honeybees do not hibernate. They remain active in the hive and will cluster together to stay alive. It is only the female bees that are left in the hive in the winter. The male drones all die off and leave the female workers and the queen to keep the colony alive.
At What Temperature Do Bees Die?
Bees stay inside the hive during the winter when the weather is cold, wet, and windy. Once the temperatures outside drop to around 57F, the bees will begin to cluster to keep the internal temperature of the hive up. The queen is at the center of the cluster with the worker bees surrounding her. The bees will spend the winter months eating honey and ‘shivering’ to maintain a constant heat.
The temperature at the center of the winter cluster can reach around 100F, but at the outer edge of the cluster, the temperature is more likely to be around 50F. It is the above-mentioned winter bees that form the outer edge of the cluster. These bees have different physical characteristics to summer bees in that they have more fat reserves, have larger hypopharyngeal glands, and have a longer lifespan.
If temperatures were to drop below 50F within the hive, the bees would struggle to survive. If a bee’s body temperature drops to 41F then it will be unable to shiver to keep warm and will inevitably die.
How Can Beekeepers Help Their Bees Survive the Winter?
Bees are great at keeping the entire colony warm during the winter, but beekeepers can do their bit to help the bees’ chances of survival. If you have recently started keeping bees, there are many things that you can do to prepare your hives for the colder winter months.
Depending on where you live and how harsh winters are there, you may or may not choose to bring your hives indoors for shelter. I obviously don’t mean into your home, but you may have an outbuilding that could house the hive over the winter. This makes it easier for you to control humidity and temperature.
Other beekeepers will wrap their hives with insulation board or tar paper as this helps to keep the walls within the hive warm and dry. Furthermore, wrapped hives are warmer, meaning the bees do not have to expend as much energy trying to maintain a constant temperature. This means that they are likely to eat less honey.
If you are wrapping your hive, be sure to keep it well ventilated or the bees could end up with a fungal disease that could wipe out the entire colony. It is vital that your hive is kept both warm and dry during the winter months.
If you are leaving your hive outside during the winter, you may want to move it to a sheltered area as it is the windchill that often poses the biggest threat to a hive.
Do You Need to Feed Your Bees Over Winter?
One question that is asked quite a lot is whether beekeepers need to feed their bees during the winter months. After all, bees are typically unable to forage for nectar at this time of year.
A well-established hive will have plenty of stores to keep the bees alive and well during the winter, provided, of course, that the beekeeper has not taken too much honey from the hive. Experienced beekeepers know just how much to take from their hives to ensure the wellbeing of their colony but those who are new to beekeeping will often make the mistake of harvesting too much honey, particularly in the first year.
This is why it is recommended not to take honey from a hive in its first year. The reason is that the bees will not have had enough time to grow in numbers while also making enough honey for themselves and you. You may even need to feed your hive with sugar syrup in the fall to prevent the bees from starving over winter.
Why Do Bees Leave the Hive in Winter?
Although bees do not forage for food in the winter, they do need to leave the hive from time to time to relieve themselves of waste. They will typically wait until the external temperature exceeds 50F, when they will leave the hive to defecate before returning to the cluster once more.
Bees do not hibernate during the winter months. The male drones die off while the female bees are left to ensure the survival of the colony. They do this by forming a cluster with every bee in the hive surrounding the queen and using their shivering muscles to create heat within the hive. Winter bees are larger and have a longer lifespan than summer bees and they form the outer edge of the cluster where temperatures are around 50F. In the center of the cluster where the queen is the temperature can reach 100F. Bees typically only leave the hive in the winter to defecate and only when the external temperature exceeds 50F.