Effect of Artificial Prolonged Wintering on Emergence and Survival of Osmia Rufa Adults

This study discusses the longevity and emergence rate of O. rufa males and females after an extended wintering period in artificial conditions. Experimental activation of the wintering bees was carried out every fifteen days, starting at the end of March and finishing at the beginning of June (25 March, 9 April, 24 April, 9 May, 24 May, 8 June). In our study, the shortest emergence time (5 days) was observed in females that overwintered for at least 220 days and were activated at the beginning of May or later. Their mean emergence time in the last three terms was similar and ranged from 4.6 to 5.1 days. Prolonged wintering increased female emergence dynamics in May and June. Half of the emerged males in our study lived up to 28 days when activated during the first term, and up to 15 days when activated during the last one. In females, half of the bees lived up to 64 and 20 days, respectively.