LATE EVENING VENTILATION OF THE NEST BY THE BEES. What is the essence of this phenomenon.

 We all had the opportunity on summer evenings, especially with a good honey flow, to observe how a mass of bees begin to ventilate the hive. A powerful rumble fills the entire apiary and does not subside until the morning. We have always believed that this is the bees remove moisture from the nectar. Not a bad idea... But why don't they do it during the day, at the hottest time of the day, when water from nectar evaporates better? At that time we don't see strong ventilation! It would seem to be a paradox, but no. Everything is logical if we turn to the statement that bees are able to maintain optimal humidity in the hive for hatching brood. We do not know what "sensors" bees have, but we can assume that they sense humidity in conjunction with temperature, that is, they respond to effective temperature, which is the derivative of absolute temperature and humidity.

So, what is actually happening in our belief in the hive and why powerful ventilation begins only in the evening?

During the day, the bees perform their usual work of bringing nectar, which they lay out first of all near open brood. And not because it needs to be fed with fresh nectar, but because water evaporating from it, raises humidity of air around the tender young brood - eggs and young larvae. After all, it is known from the works of scientists that the best survival of eggs and young larvae is observed at a relative humidity of about 90%. At the same time, we assume that the honey collection takes place during the warmest, if not the hottest time of the summer season.

So, what is the reason for this powerful evening ventilation ... And here's what! During the day, at the hottest time, water evaporating from nectar raises the absolute humidity in the hive, but the bees do not notice this yet, since the phenomenon is that they apparently feel not absolute, but relative humidity, and the higher the temperature, the less it gets! The same amount of water vapor dissolved in the same volume of air will show different relative humidity at different temperatures! At high temperatures, it will be much lower than at low! If you cool any room containing water vapor in the atmosphere, then sooner or later dew will occur! The temperature at which this can occur at certain humidity is called the "dew point". That's what bees are afraid of!

In the evening, as the temperature drops to the cold of the night, the bees feel how the relative humidity rises, which can cause vapors to condense into dew. It is this increase in relative humidity that causes the bees to intensively remove getting colder and colder moist air from the hive. That is why there is no need to ventilate the hive during the daytime - after all, at high daytime temperatures, the relative humidity of the air in the hive is not high at all, no matter how much fresh nectar is brought by the bees!

So, it can be argued that the powerful ventilation of the hive in the evening is directly related to both the supply of significant volumes of nectar and a significant decrease in temperature in the evening and at night.

ERRONEOUS CONCEPTION ABOUT COOLING THE NEST BY THE BEES DUE TO HANGING WATER DROPS ON HONEYCOMBS IN THE NEST.

Based on our scientific researches and materials of the works of famous scientists, we believe that the classical theory of cooling the nest by the bees by hanging water droplets on honeycombs is completely untenable!

Insects, being cold-blooded, become active at higher temperatures and therefore "like" hot weather. The fact that the bees ventilate the hive during the day can only mean that in conditions of heat and the corresponding reduced concentration of oxygen in the air, the bees simply need more efficient ventilation! What about water droplets?

It is known that for high-quality hatching of queens in an incubator, a temperature of 35 degrees Celsius is maintained at a relative humidity of 70%. Everyone knows this... But why should one think that some other conditions are needed for the brood of worker bees?

And what does the parameter "humidity" mean? Absolute humidity is the amount of moisture contained in one cubic meter of air. Absolute humidity is used when it is necessary to compare the amount of water in the air at different temperatures or over a wide range of temperatures. Usually measured in g/m³. But due to the fact that at a certain air temperature it can contain only a certain amount of moisture as much as possible (with an increase in temperature, this maximum possible amount of moisture increases, with a decrease in air temperature, the maximum possible amount of moisture decreases), the concept of relative humidity was introduced. Relative humidity is the ratio of the mass fraction of water vapor in the air to the maximum possible at a given temperature.

For us, this means that as the temperature in the bee nest rises, the relative humidity of the air in the nest drops !!!! Thus, when the temperature rises, it becomes necessary, no, not to cool the nest ... The bees need heat, but to humidify the airin the nest!

Water, evaporating, only increases the humidity, which is necessary so that the open brood, with its delicate skin, does not dry out and turn into "dried fruits". That's what the water in the hive is for! That's why the bees begin to carry it in early spring ( when relative humidity can be only 20%) as soon as the first mass brood appears, and not to cool the nest when it's already cold enough in spring!

It seems that this is also the reason why the bees accumulate freshly brought nectar around the brood in summer, and only after a certain amount of water has evaporated, they transfer it to honey supers! Moisture from nectar evaporating creates the necessary humidity around the brood during hot and dry summer days!

Thus, it can be assumed that in springtime, bees carry water not only, and not so much, in order to moisten sugar or soak crystallized honey, but in order to create conditions for growing brood in the absence of a nectar flow, which, drying up, could humidify the air in the nest! Therefore, when we see bees near a puddle, or on a drinking bowl, we can say for sure that an enhanced spring brood hatching has begun!

In summer, bees carrying water into the hive in hot weather become an indicator of the absence of a significant honey flow in nature. The secretion of nectar is weak and its influx into the hive cannot provide natural moisture maintenance in the nest. Additional humidification of the air is required due to the water brought into the hive.

This is what the phenomenon of hanging water droplets on honeycombs by the bees looks like in reality!