The way that biological and chemical stressors and environmental factors interact to affect bees and contribute to population decline is still not well understood. The mechanisms are complex and the potential number of different combinations and interactions is hard to estimate. It is a scientific puzzle.
EFSA has set itself the task of trying to understand how some of the pieces of the puzzle fit together. With every new insight and connection we hope to improve our understanding the complex issue of bee decline.
The aim of this multi-annual project, therefore, is to develop a holistic approach to the risk assessment of multiple stressors in honeybees (MUST-B), with the ultimate goal of developing a software tool that can assess the combined threat posed to bee colonies in their natural environment by parasites, infectious agents, pesticides and other stressors.
MUST-B is being overseen by an EFSA Working Group made up of experts from a variety of scientific backgrounds. The work plan envisages a number of interlinked activities to be carried out either in-house or in collaboration with external specialists, researchers, data analysts and bodies such as EU Member States, the European Commission, EU sister agencies, and the European Reference Laboratory for Honeybee Health.
The starting point is to gather evidence on co-exposures and interactions and to establish exactly what constitutes a healthy honeybee colony. This question is being addressed by a working group of EFSA’s Animal Health and Welfare Panel, which is establishing a set of harmonised indicators that can be used to assess the health status of a colony. As well as providing the basis for the development of the model, the findings of this group will be used to design field survey protocols.
Work on modelling the impact of stressors and other factors on bees has been initiated by EFSA’s pesticide experts, who produced a report on the suitability of the BEEHAVE model for assessing risks from pesticides and other stressors.
Another area of focus is surveillance and monitoring. In 2008, EFSA conducted a survey on existing bee surveillance systems in the EU and, following its recommendations, the European Commission established the EU Reference Laboratory (EURL) for Honeybee Health and funded an EU wide monitoring programme on honeybee mortalities and diseases in Europe (EPILOBEE). The results of this programme showed a geographic north-south trend in mortality, but there is some uncertainty surrounding the consistency and robustness of the results. EFSA and the EURL will continue to collaborate in this and other areas related to MUST-B.
As well as projects that fall under the MUST-B umbrella, EFSA continues to carry out activities that are directly relevant to bee health, such as its risk assessments of neonicotinoid pesticides and bee pathogens. The conclusions – and data – generated by these activities will be valuable resources for the various MUST-B projects.
In 2012, EFSA set up an internal multidisciplinary task force on bees and organised a scientific colloquium entitled “Towards holistic approaches to the risk assessment of multiple stressors in bees”. The task force produced an inventory of EFSA’s work in the area of bee health and consulted a wide range of stakeholders – such as the European Commission and Member States – to identify knowledge gaps in research and to make recommendations to move towards an integrated approach to the risk assessment of bees. The MUST-B project was one of the results of this intelligence-gathering work and of the EU’s increased efforts to tackle bee decline.