A method for remote monitoring of activity of honeybee colonies by sound analysis

An automated system is described for continuous recording of sound emission by honeybee (Apis mellifera) colonies as a measure of activity. Colonies were monitored throughout the year. Output of sound, with respect to both amplitude and duration, was greatest in summer, declined to a low level in autumn, and ceased by December, resuming in mid-January. Colonies from which light was excluded during the winter re-.established their normal seasonal pattern at the same time as those exposed to the natural photoperiod. During the active season, diurnal activity was generally high in daytime and low at night; however, initiation of activity did not coincide closely with sunrise nor cessation with sunset. Most of the sound was at frequencies around 300, 410 and 510 Hz.