Results of Annual Monitoring of Honey Bee Colony Winter Losses in Ukraine: Winter 2019–2020

Purpose. To estimate honey bee (Apis mellifera Linnaeus, 1758) colony winter loss rate for Ukraine after the winter 2019–2020 in the context of international COLOSS survey. Methods. Analysis of the results of the survey of Ukrainian beekeepers on A. mellifera colonies survival after the winter 2019-2020 by using the questionnaire developed by the coordinators of COLOSS international monitoring group. Unified approaches to data collection and statistical processing have been used. Valid protocols from 702 respondents from five physical-geographical zones of Ukraine have been analysed. Results. Honey bee colony winter loss rates for Ukraine after the winter 2019-2020 was 9.29%, the mortality rate was 5.41 %; the losses due to unsolvable queen problems – 2.19 %, and due to natural disasters – 1.69 %. The total losses in the steppe zone of Ukraine were 16.08%, significantly exceeding this indicator in the forest-steppe zone (8.94%), the zone of deciduous forests (6.73%) and the Ukrainian Carpathians (8.14%). The most common sign of dead colonies in Ukraine was the presence of a large number of dead bees in or in front of the hive (31.3 %) and unknown symptoms (37,3 %). The majority of Ukrainian beekeepers (50.7%) did not notice any difference in wintering of the colonies going into winter with a new queen in comparison with the old one. Among antivarroa drugs, the majority of respondents preferred products based on amitraz (fumigation – 50.8%, in plates – 15.7%) and flumethrin (20.0%). We confirmed statistically lower level of winter losses in colonies treated with amitraz (fumigation), whereas colonies treated with formic acid (long-term) had higher losses. Conclusions. Honey bee (Apis mellifera Linnaeus, 1758) colony winter loss rate for Ukraine after the winter 2019–2020 was 9.29% and decreased slightly compared to the last year (11.18%) and the year before last (11.26%). It was almost twice lower than the average for the countries participating in COLOSS international monitoring (18,1%) (Gray, 2021). The highest losses were observed in the steppe zone of Ukraine, whereas the lowest in the Ukrainian Carpathians. The smaller beekeeping operations with at most 50 colonies suffered significantly higher losses 12.66%) compared to medium and large ones (9.48% and 6.52%, respectively). The number of beekeepers treating colonies against varroosis was 90.6%, and all of them mentioned that they had pre-monitored the level of Varroa infestation.