The influence of various physical and biological factors of the environment on honeybee activity. An examination of the relationship between activity and solar radiation

A review of the literature shows that those who have studied the influence of solar radiation on honeybee activity are agreed that it is an important limiting factor. This is in general agreement with observations made by beekeepers. Brittain et al. (1933) give a detailed account of the effects of solar radiation on honeybee activity, and claim that, as might be expected from the work of Bertholf (1931, 1931 a), a higher correlation between activity and the intensity of ultra-violet radiation exists than between activity and radiation of clear light. However, fresh analysis of their data throws considerable doubt on their conclusions. New data were collected which clearly show an association between variations in honeybee activity and the radiation of clear light.