Monitoring of swarming sounds in bee hives for prevention of honey loss

Beekeeping, known as one of the oldest forms of agriculture, is following the evolution of human technology, and in its complexity there is more and more need to control the honey production with what modern technology can offer. In a view of animal production, honey is included since the farmer has interest in producing big quantities of this substance according to the best blooming time, the presence of parasites, the genetic strain of his bees and the swarming periods of the honeybees (queen and her workers leaving the hive). This last fact has a big economic interest for the beekeeper as swarming means honey loss, as the bees start collecting the honey to migrate. Here for a method that enables the prediction of the swarming is required to prevent the queen from leaving the hives. In this experiment an acoustic method is proposed to predict the swarming period. Three hives were monitored during 270 hours. The microphones were placed inside the hives together with a temperature and humidity sensor. The sound were recorded with a sample rate of 2kHz, and analyzed via Matlab and Cool Edit Pro. During this period 9 swarming activities occurred. There is an increase in the power spectral density at about 110Hz, approaching to swarm the sound increased in amplitude and frequency to 300 Hz but sometimes a rapid change occurred from 150 to 500 Hz. Another finding indicating the initiation of a swarming period is the increase in temperature from 33 C to 35 C until the actual time of swarming, where the temperature starts dropping to 32 C. This is illustrated in figure 6. Once there is a lot of activity, the ventilation causes the temperature to drop once the swarming begins. Less informations come from the correlation between sound and humidity since this parameter is too much influenced by the external temperature and no significant variation occurred according to a swarm. This increase of temperature, together with the changes in acoustical features of the sound recorded in the hive, may be used as a predictor for swarming of the bees to reduce honey loss.