Comparison of apiculture and winter mortality of honey bee colonies (Apis mellifera) in Austria and Czechia

Honey bees are the most important managed pollinators and provide income because of bee products. In Austria and Czechia, we monitored winter losses of honey bee colonies and also collected information on the apicultural sector, hive management, population dynamics and treatment against the mite Varroa destructor from 2013-14 to 2016-17. Numbers of beekeepers and colonies, colony density and percentage of beekeepers in human population are higher in Czechia than in Austria. Winter loss rates of honey bee colonies ranged from 8.1% to 28.4% in Austria and 6.4% to 19.4% in Czechia, with significantly higher loss rates in all 4 investigated winters in Austria. The portion of colonies lost because of living colonies with unsolvable queen problems ranged from 3.6 to 4.4% in Austria and from 2.2 to 3.0% in Czechia. Despite of colony losses during winter, colony production in summer allows for compensation or even expansion of colony populations in both countries. We identified differences between the two countries in the treatments applied by beekeepers against the parasitic varroa mite. In Austria, organic acids are most commonly used, whereas the application of synthetic acaricides is widely spread in Czechia. Our study points at the better understanding of apiculture and the importance of international comparisons to facilitate our knowledge on honey bee colony losses.