Gray, A. - Department of Mathematics and Statistics, University of Strathclyde, Glasgow, United Kingdom
Adjlane, N. - Department of Agronomy, Université M’hamed Bougara, Boumerde, Algeria
Arab, A. - Department of Animal Science, University of Tehran, Karaj, Iran
Ballis, A. - Chambre d'agriculture d'Alsace, Strasbourg, France
Brusbardis, V. - Latvian Beekeepers Association, Jelgava, Latvia
Charrière, J.-D. - Agroscope, Swiss Bee Research Center, Bern, Switzerland
Chlebo, R. - Department of Animal Science, Slovak University of Agriculture, Nitra, Slovakia
Coffey, M.F. - Department of Biological Sciences, University of Limerick, Limerick, Ireland
Cornelissen, B. - Wageningen Plant Research, Wageningen University & Research, Wageningen, Netherlands
Amaro da Costa, C. - Agriculture School, Politechnic Institute of Viseu, Viseu, Portugal
Dahle, B. - Norwegian Beekeepers Association, Kløfta, Norway
Danihlík, J. - Department of Biochemistry, Palacký University Olomouc, Olomouc, Czech Republic
Dražić, M.M. - Ministry of Agriculture, Zagreb, Croatia
Evans, G. - Welsh Beekeepers Association, Northop, United Kingdom
Fedoriak, M. - Department of Ecology and Biomonitoring, Yuriy Fedkovych Chernivtsi National University, Chernivtsi, Ukraine
Forsythe, I. - The Agri-Food and Biosciences Institute, Belfast, United Kingdom
Gajda, A. - Institute of Veterinary Medicine, Department of Pathology and Veterinary Diagnostics, Warsaw University of Life Sciences, Warsaw, Poland
de Graaf, D.C. - Honeybee Valley, Ghent University, Ghent, Belgium
Gregorc, A. Faculty of Agriculture and Life Sciences, University of Maribor, Maribor, Slovenia
Ilieva, I. - Department of Developmental Biology, University of Plovdiv "Paisii Hilendarski", Plovdiv, Bulgaria
Johannesen, J. - DLR Fachzentrum für Bienen und Imkerei, Mayen, Germany
Kauko, L. – Finnish Beekeepers Association, Köyliö, Finland
Kristiansen, P. - Swedish Board of Agriculture, Joenkoeping, Sweden
Martikkala, M. - Finnish Beekeepers Association, Kangasala, Finland
Martín-Hernández, R. - Centro de Investigación Apícola y Agroambiental de Marchamalo (IRIAF), Marchamalo, Spain
Medina-Flores, C.A. - Faculty of Veterinary Medicine and Animal Science, University of Zacatecas, Zacatecas, Mexico
Mutinelli, F. - Istituto Zooprofilattico Sperimentale delle Venezie, NRL for honey bee health, Legnaro, Italy
Patalano, S. - Institute of Basic Biomedical Sciences (IBBS), B.S.R.C «Alexander Fleming», Vari, Greece
Raudmets, A. - Estonian Beekeepers Association, Tallinn, Estonia
Martin, G.S. - Walloon Agricultural Research Centre (CRA-W), Gembloux, Belgium
Stevanovic, J. - Department of Biology, Faculty of Veterinary Medicine, University of Belgrade, Belgrade, Serbia
Uzunov, A. - Faculty of Agricultural Sciences and Food, Ss. Cyril and Methodius University, Skopje, North Macedonia
Vejsnaes, F. - Danish Beekeepers Association, Sorø, Denmark
Williams, A. - School of Computer Science and Informatics, De Montfort University, Leicester, United Kingdom
Zammit-Mangion, M. - Department of Physiology and Biochemistry, University of Malta, Msida, Malta
Brodschneider, R. - Institute of Biology, University of Graz, Graz, Austria
This article presents managed honey bee colony loss rates over winter 2018/19 resulting from using the standardised COLOSS questionnaire in 35 countries (31 in Europe). In total, 28,629 beekeepers supplying valid loss data wintered 738,233 colonies, and reported 29,912 (4.1%, 95% confidence interval (CI) 4.0–4.1%) colonies with unsolvable queen problems, 79,146 (10.7%, 95% CI 10.5–10.9%) dead colonies after winter and 13,895 colonies (1.9%, 95% CI 1.8–2.0%) lost through natural disaster. This gave an overall colony winter loss rate of 16.7% (95% CI 16.4–16.9%), varying greatly between countries, from 5.8% to 32.0%. We modelled the risk of loss as a dead/empty colony or from unresolvable queen problems, and found that, overall, larger beekeeping operations with more than 150 colonies experienced significantly lower losses (p < 0.001), consistent with earlier studies. Additionally, beekeepers included in this survey who did not migrate their colonies at least once in 2018 had significantly lower losses than those migrating (p < 0.001). The percentage of new queens from 2018 in wintered colonies was also examined as a potential risk factor. The percentage of colonies going into winter with a new queen was estimated as 55.0% over all countries. Higher percentages of young queens corresponded to lower overall losses (excluding losses from natural disaster), but also lower losses from unresolvable queen problems, and lower losses from winter mortality (p < 0.001). Detailed results for each country and overall are given in a table, and a map shows relative risks of winter loss at regional level.
Gray, A. - Department of Mathematics and Statistics, University of Strathclyde, Glasgow, United Kingdom
Adjlane, N. - Department of Agronomy, Université M’hamed Bougara, Boumerde, Algeria
Arab, A. - Department of Animal Science, University of Tehran, Karaj, Iran
Ballis, A. - Chambre d'agriculture d'Alsace, Strasbourg, France
Brusbardis, V. - Latvian Beekeepers Association, Jelgava, Latvia
Charrière, J.-D. - Agroscope, Swiss Bee Research Center, Bern, Switzerland
Chlebo, R. - Department of Animal Science, Slovak University of Agriculture, Nitra, Slovakia
Coffey, M.F. - Department of Biological Sciences, University of Limerick, Limerick, Ireland
Cornelissen, B. - Wageningen Plant Research, Wageningen University & Research, Wageningen, Netherlands
Amaro da Costa, C. - Agriculture School, Politechnic Institute of Viseu, Viseu, Portugal
Dahle, B. - Norwegian Beekeepers Association, Kløfta, Norway
Danihlík, J. - Department of Biochemistry, Palacký University Olomouc, Olomouc, Czech Republic
Dražić, M.M. - Ministry of Agriculture, Zagreb, Croatia
Evans, G. - Welsh Beekeepers Association, Northop, United Kingdom
Fedoriak, M. - Department of Ecology and Biomonitoring, Yuriy Fedkovych Chernivtsi National University, Chernivtsi, Ukraine
Forsythe, I. - The Agri-Food and Biosciences Institute, Belfast, United Kingdom
Gajda, A. - Institute of Veterinary Medicine, Department of Pathology and Veterinary Diagnostics, Warsaw University of Life Sciences, Warsaw, Poland
de Graaf, D.C. - Honeybee Valley, Ghent University, Ghent, Belgium
Gregorc, A. Faculty of Agriculture and Life Sciences, University of Maribor, Maribor, Slovenia
Ilieva, I. - Department of Developmental Biology, University of Plovdiv "Paisii Hilendarski", Plovdiv, Bulgaria
Johannesen, J. - DLR Fachzentrum für Bienen und Imkerei, Mayen, Germany
Kauko, L. – Finnish Beekeepers Association, Köyliö, Finland
Kristiansen, P. - Swedish Board of Agriculture, Joenkoeping, Sweden
Martikkala, M. - Finnish Beekeepers Association, Kangasala, Finland
Martín-Hernández, R. - Centro de Investigación Apícola y Agroambiental de Marchamalo (IRIAF), Marchamalo, Spain
Medina-Flores, C.A. - Faculty of Veterinary Medicine and Animal Science, University of Zacatecas, Zacatecas, Mexico
Mutinelli, F. - Istituto Zooprofilattico Sperimentale delle Venezie, NRL for honey bee health, Legnaro, Italy
Patalano, S. - Institute of Basic Biomedical Sciences (IBBS), B.S.R.C «Alexander Fleming», Vari, Greece
Raudmets, A. - Estonian Beekeepers Association, Tallinn, Estonia
Martin, G.S. - Walloon Agricultural Research Centre (CRA-W), Gembloux, Belgium
Stevanovic, J. - Department of Biology, Faculty of Veterinary Medicine, University of Belgrade, Belgrade, Serbia
Uzunov, A. - Faculty of Agricultural Sciences and Food, Ss. Cyril and Methodius University, Skopje, North Macedonia
Vejsnaes, F. - Danish Beekeepers Association, Sorø, Denmark
Williams, A. - School of Computer Science and Informatics, De Montfort University, Leicester, United Kingdom
Zammit-Mangion, M. - Department of Physiology and Biochemistry, University of Malta, Msida, Malta
Brodschneider, R. - Institute of Biology, University of Graz, Graz, Austria
This article presents managed honey bee colony loss rates over winter 2018/19 resulting from using the standardised COLOSS questionnaire in 35 countries (31 in Europe). In total, 28,629 beekeepers supplying valid loss data wintered 738,233 colonies, and reported 29,912 (4.1%, 95% confidence interval (CI) 4.0–4.1%) colonies with unsolvable queen problems, 79,146 (10.7%, 95% CI 10.5–10.9%) dead colonies after winter and 13,895 colonies (1.9%, 95% CI 1.8–2.0%) lost through natural disaster. This gave an overall colony winter loss rate of 16.7% (95% CI 16.4–16.9%), varying greatly between countries, from 5.8% to 32.0%. We modelled the risk of loss as a dead/empty colony or from unresolvable queen problems, and found that, overall, larger beekeeping operations with more than 150 colonies experienced significantly lower losses (p < 0.001), consistent with earlier studies. Additionally, beekeepers included in this survey who did not migrate their colonies at least once in 2018 had significantly lower losses than those migrating (p < 0.001). The percentage of new queens from 2018 in wintered colonies was also examined as a potential risk factor. The percentage of colonies going into winter with a new queen was estimated as 55.0% over all countries. Higher percentages of young queens corresponded to lower overall losses (excluding losses from natural disaster), but also lower losses from unresolvable queen problems, and lower losses from winter mortality (p < 0.001). Detailed results for each country and overall are given in a table, and a map shows relative risks of winter loss at regional level.