Why bees leave/abscond their hives in fall?

In the last few days, we have been getting a lot of questions about why bees leave/abscond their hives. We are all familiar with swarming, which represents splitting the colony, one part of the colony leaves and another stays in the hive. However, abscond is quite another phenomenon where the bees completely leave the hive and leave all the honey. This urges the question, why do bees

leave the hive before winter arrives?

Why is absconding happening?

This phenomenon, as well as many others related to the bees, is not fully understood. However, based on the experience we can make some conclusions. At least one of the following few things exists right before the absconding of the colony in fall:

• Harassment of the colony by some wild animals or beekeepers;
• The hive is massively attacked by predators such as ants, yellowjackets or wax moths;
• There is an enormous shortage of nectar that contributes to a shortage of stored food;
• Many beekeepers have observed that this occurs even after the autumn treatment of varroa mites.

Actually, the colony feels threatened and the hive becomes too stressful for the bees, they feel they have little chance of survival in the hive and decide to leave. This is the main reason why bees leave/abscond their hives.

However, this is a process. Just like swarming, the colony is preparing for absconding the hive. The queen stops laying eggs and slims down, so she can fly, they stop foraging, launch scouts to find a new place to live.

Such a colony is very weak. It has no chance of surviving the winter. The colony has no food supply, no nectar, no honeycomb and of course not enough time to prepare for the winter. If you catch such colony, with a lot of feeding: sugar syrup, honey, and pollen there is a chance that it will survive the winter.