Honeybees are amazing insects that provide us with honey and pollinate many crops. But how do they survive the cold winters, especially in regions where the temperature can drop below zero?
Many people believe that honeybees naturally insulate their colonies against the cold by building thick walls of wax and propolis, a sticky substance made from plant resins.
However, a recent study by a researcher from the University of Leeds challenges this widespread belief and reveals that honeybees do not rely on insulation, but rather on their own body heat to keep warm.
Honeybees generate heat by shivering
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Dr. Tom Seeley, a professor of entomology at the University of Leeds, conducted a study on honeybees living in northern Spain, where the winters are mild but sometimes frosty.
He found that honeybees use hollow electricity poles as nesting cavities, which offer little insulation and expose the colonies to the outside temperature.
He measured the temperature inside and outside the nests and found that the honeybees maintained a constant temperature of about 35°C inside the nest, regardless of the outside temperature, which ranged from 5°C to 25°C.
Dr. Seeley explained that honeybees generate heat by shivering, just like humans do when they are cold. Honeybees have a special group of muscles in their thorax that vibrate rapidly and produce heat.
The honeybees cluster together in a tight ball and shiver to warm up the nest. The outer layer of bees acts as a shield to prevent heat loss, while the inner layer of bees feeds on the honey stored in the combs and fuels the shivering process.
Honeybees need food, not insulation, to survive the winter
Dr. Seeley's study suggests that honeybees do not need insulation to survive the winter, but rather food. He found that the amount of honey stored in the nests was the main factor that influenced the colonies' chances to survive the winter.
The more honey the bees had, the more likely they were to survive.
He also found that natural areas in the surroundings of the nests, such as forests and meadows, promoted the survival of the colonies, as they provided more food resources for the bees during the summer and autumn.
Dr. Seeley's findings have important implications for beekeepers and conservationists.
According to him, beekeepers should not worry too much about insulating their hives, but rather focus on providing enough food for their bees, either by leaving enough honey in the hives or by supplementing their diet with sugar syrup.
He also said that conservationists should protect and restore natural habitats for wild bees, as they are essential for their survival and diversity.
Honeybees face multiple threats from human activities
However, honeybees face multiple threats from human activities, such as pesticide exposure, land-use intensification, invasive species, and diseases, which have caused significant losses of managed and wild honeybee colonies around the world.
These threats could affect the ability of honeybees to cope with cold winters, as they could reduce their food availability, weaken their immune system, and increase their parasite load.
Therefore, it is crucial to support honeybee health and resilience, not only for their own sake, but also for ours.
Honeybees pollinate more than 80 agricultural crops, which account for about a third of what we eat. Without them, our food security and prices would be at risk.
Moreover, honeybees are part of the biodiversity of our planet, and their loss would have negative impacts on the functioning of ecosystems and the services they provide.
They are remarkable creatures that have adapted to survive the cold winters by shivering. However, they need our help to overcome the challenges they face from human activities.
By providing them with enough food, protecting their natural habitats, and reducing their exposure to harmful substances and pathogens, we can ensure their survival and well-being, as well as ours.
