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Food Safety

Study on honey bee colony mortality

The second and final report on the recently finished pan-European epidemiological study on honey bee colony losses (EPILOBEE 2012-2014 ) has been prepared by the EU reference laboratory for bee health. The objective of the two-year programme was to get a state of play of honey bee colony losses on a harmonised basis in each of the participating EU countries.

Simultaneously, the main honey bee diseases were investigated based on case definitions and sampling protocols provided by the EURL. This report aims at presenting the main results of the second year of EPILOBEE on colony mortality and on the prevalence of infectious and parasitic diseases, and to compare these results with those obtained during the previous year.

The mortality rates for winter 2013 – 2014 showed a narrower range (2.4% to 15.4%) than the mortality rates observed during the winter 2012 – 2013. The decrease in overwintering colony mortality rates over these two years is noticeable. However, this has to be interpreted with caution. Thus, the decrease in colony losses observed during 2013 – 2014 will be fully analysed, carefully interpreted and put into perspective in cooperation with the European Food Safety Authority. The EPILOBEE project was co-financed by the European Commission (3,3 mEUR and 1,85 mEUR respectively) and by the 17 participating EU countries.

Overwintering colony mortality (winter 2012–2013 and winter 2013–2014)

Figure 1: Winter colony mortality rates in the Member States of the European Union recorded in:

EPILOBEE 2012 – 2013 (Revised map):


EPILOBEE 2013 – 2014:


Some conclusions after two years of the study

  • Rates of colony mortality differed from one year to another towards a decrease in the second year.
  • Significant regional differences in colony losses were also observed.
  • Climate might have influenced winter colony losses over the two years.
  • European and national surveillance systems benefited from this experience.
  • It will facilitate future implementation of projects (e.g. explanatory studies) studying other risk factors affecting colony health.

Its robust methodology can be implemented and used as necessary, adapted to specific needs as appropriate for further work such as applied research, policy development, routine surveillance or to cross-check with data from other sources (e.g. from national or regional monitoring, from international standardised beekeeper surveys etc.).

Background: a European Food Safety Authority (EFSA) project in 2009 indicated that the honey bee surveillance systems in the EU countries were weak. There was a lack of representative official data at country level and comparable data at EU level to estimate the extent of colony mortalities.

With the guidance and technical assistance of the EU reference laboratory and the national reference laboratories, the previous study (EPILOBEE 2012-2013 ) addressed for the first time these weaknesses by harmonising the data collection methods.

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