Emergency heating - the last opportunity to heat the nest.

It is well known to everyone that bees maintain the temperature with particular precision in the nest where the development of eggs and larvae takes place. The correct and stable temperature is very important in the transformation of larva into pupa, and pupa into bee. The conditions in which bees have to live in middle latitudes are not very comfortable for them. That is why, almost throughout the year, the bees have to heat their nest, and sometimes the entire hive. But this heating, which occurs under normal conditions of life of bee colony, usually consists of heating due to the release of metabolic heat by the bodies of bees and from heating due to the release of heat during the vibration of the thorax muscles of the bee. It's like a freezing man's shiver. A little muscle work contributes to the release of additional heat.

This type of heating is used by the bees in winter inside winter cluster, in the spring when heating brood, before swarming when heating the entire hive in order to provide the queen with a maximum suitable area for laying eggs, in summer when rearing brood and in autumn when heating the last brood and the bee cluster itself.

fig.1

But, there are situations in the life of bees when such heat is not enough. This is possible with a sharp cooling of the nest in spring or of a cluster of bees in winter, or  in summer, with a shortage of bees in offshoot to heat the queen cells. Then the bees use emergency heating.

Under acoustic control, this is the lowest frequency signal in the hive, presumably generated by bees vibrating not only with the muscles of thorax, but also with partially opened wings. This, it seems to us, is already not just alike shivering, when we are cold, but like clapping our hands and jumping or other more energy-intensive physical exercises that we do when we are very cold. Such movements allow bees to generate maximum heat without creating air movement in the nest. At the same time, energy losses require its replenishment, and therefore emergency heating signals (n1 fig. 1), as a rule, are accompanied by signals for in-hive works and works with honey (n2 fig. 1). What can be assumed if you see such a signal on the diagram of Apivox Smart Monitor ...

1. In summer and spring, there are too few bees in offshoot for calm heating of brood and queen cells. Especially queen cells.

2. You opened the hive in winter at low negative temperatures for about 5-10 minutes. The bees began to actively warm cluster in order  to restore an acceptable temperature in the crust of cluster.

3. If in winter and autumn, when the family of bees should be in winter cluster, you received such a diagnosis without opening the hive, then most likely there are very few bees left in the colony and the colony will soon die. As a rule, this happens when the family is severely affected by Varroa mites.

 

This is exactly what is shown in Figure 1. Having received such a diagnosis during acoustic control of the family from the upper part of the frames covered with textile, we saw two main signals - emergency heating and work with honey. Our assumption was that there are too few bees in the colony and they continuously eat honey and try to warm themselves. Visual control showed that  in the colony remained about 30-40 alive bees, which sat in a small lump on just one frame with honey, actively consumed it and tried to warm themselves. The colony died from being attacked by Varroa mites, showing an almost classic version of the Collapse of Bee Colonies - the hive is full of honey, and there are no bees or a few dozen left.

In any case, it can be said that appearance of such a signal is a sign of some kind of problem that requires the beekeeper to personally control the state of the family and, possibly, immediately help her.