Результати щорічного моніторингу втрат бджолиних колоній в Україні: зимівля 2017-2018 рр

Abstract

Decline of honey bee colonies remains a global problem. It may affect catastrophically both ecosystems and the global economy. Here we present the results of the fourth year of a research project on bee colony losses in Ukraine over winter 2017-2018, conducted in the framework of international monitoring coordinated by the non-profit honey bee research association COLOSS. Overall winter loss rate and the mortality rate over winter 2017-2018 were significantly lower compared to the previous year: overall winter loss rate – 11.3% (95 % СІ 10.0-12.6); mortality rate – 6.7% (95 % СІ 5.8-7.7); rate of colony loss due to unsolvable queen problems – 2.1% (95 % СІ 1.6-2.7) and due to natural disasters – 2.4% (95 % СІ 2.0-3.0). Likewise previous years, the highest losses were observed in small operations (with 50 or fewer colonies). The highest overall loss rate was observed in the Steppe zone, with the highest both mortality rate and losses due to natural disasters compared to the other physiographic zones of Ukraine. Minimum mortality was recorded from deciduous forests 5.6 % (95 % CI 4.4-7.2) and the Ukrainian Carpathians 5.5 % (95 % CI 4.2-7.2). Winter losses related to queen problems varied greatly with a minimum in the Forest-Steppe zone 0.71 % (95 % CI 0.3-1.5). 83.3% of beekeepers treated their colonies against Varroa. The r-rank correlation analysis identified two potential risk factors (no or only a few dead bees in or in front of the empty hive; dead workers in cells and no food present) which revealed a weak positive correlation with both mortality rate and the rate of losses due to unsolvable queen problems.